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<title>Graduate School of Life Sciences, Tohoku University</title>
<subtitle>Latest news.</subtitle>
<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/"/>
<updated></updated>
<id>https://www.lifesci.tohoku.ac.jp/</id>
<author>
	<name>Graduate School of Life Sciences, Tohoku University</name>
</author>

	<entry>
	<title>Researchers Identify &quot;Green Thumb&quot; Molecule That Drives Leaf Stalk Growth in Plants</title>
	<link rel="alternate" type="text/html" href="https://www.tohoku.ac.jp/en/press/green_thumb_molecule_drives_growth_in_plants.html" />
	<updated>2026-09-03T10:00:00+09:00</updated>
	<summary></summary>
	<id>https://www.tohoku.ac.jp/en/press/green_thumb_molecule_drives_growth_in_plants.html</id>
</entry>	<entry>
	<title> Unleashing Potential: Vagus Nerve Stimulation Tunes Brain Blood Vessels, Enhances Learning</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2026-08-26T10:00:00+09:00</updated>
	<summary>Do you ever feel like sometimes you can master a new dance step almost immediately, while other times you struggle to nail it despite repeated practice? This might be due to skill or effort, but also to something less obvious: whether the brain is in a state that allows learning to take hold.&amp;nbsp;

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The brain does not learn in isolation from the rest of the body. Signals from internal organs continuously reach the brain through a key part of our nervous system called the vagus nerve. Researchers at Tohoku University specializing in super-network brain physiology have now demonstrated in mice that stimulating this nerve after training can promote lasting motor learning. This study reveals a previously underappreciated way in which body-to-brain signaling may support long-term learning.&amp;nbsp;

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The findings were published in iScience on August 25, 2026.

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Figure 1: Vagus nerve stimulation enhances the lasting effects of learning.
Mice received vagus nerve stimulation (VNS) immediately after being trained on an eye-movement learning task. Although VNS had little effect during training, stimulated mice showed better performance on subsequent days, indicating enhanced long-term learning.
&amp;copy; Junyu U. Chen, Yoko Ikoma, Ko Matsui

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The vagus nerve is a major communication route between the body and brain, carrying information from internal organs to the brain and signals from the brain back to internal organs. &amp;nbsp;This pathway can be modulated through vagus nerve stimulation (VNS), a clinically approved treatment for several disorders. Previous studies have investigated VNS as a neuromodulation technique that alters neurotransmitter systems, but this new study reveals another possible mechanism behind VNS: rhythmic changes in brain blood vessels.

&amp;nbsp;

The researchers developed a small cuff electrode that could remain attached to the left cervical vagus nerve of mice. They then examined VNS during horizontal optokinetic response (HOKR) learning, a cerebellum-dependent eye-movement task in which mice learn to track moving visual stripes more effectively. The response resembles the reflexive eye movements you make when standing on a platform and watching a train pass by.&amp;nbsp;

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VNS was delivered after each training session. It did not improve performance during training itself; instead, its effects emerged later. Mice receiving VNS showed stronger long-term learning on subsequent days, suggesting that stimulation acts on post-training processes supporting memory consolidation.

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&amp;quot;The key point is that VNS was delivered only after training,&amp;quot; says Professor Ko Matsui. &amp;quot;Our findings suggest that VNS may open a hidden window of opportunity for enhanced learning by making the brain environment more receptive to long-lasting change.&amp;quot;

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Figure 2: Vagus nerve stimulation produces a biphasic vascular response in the brain. 

A single train of vagus nerve stimulation (VNS) caused local blood volume near the cerebellar flocculus to decrease briefly and then increase. Two complementary fluorescence signals confirmed this characteristic vascular response.
&amp;copy; Junyu U. Chen, Yoko Ikoma, Ko Matsui

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To explore the accompanying brain changes, the team measured blood-volume dynamics near the cerebellar flocculus, a region involved in HOKR learning. Fiber photometry revealed that a single VNS train produced a biphasic vascular response: a brief decrease in local blood volume followed by a delayed increase. Repeated VNS induced rhythmic blood-volume oscillations, and mice with larger oscillations tended to show better learning on Day 5.

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&amp;quot;Our brains may be more strongly influenced by the body than we imagine,&amp;quot; says lead author Junyu Chen. &amp;quot;By tuning the brain&amp;rsquo;s metabolic environment, including rhythmic vascular movements, we may eventually unlock capacities that would otherwise remain latent.&amp;quot;

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Future studies will aim to optimize stimulation protocols in order to further clarify how the brain-body axis supports long-term plasticity. Studying this two-way route between the brain and the body will help us better understand the details of learning &amp;ndash; and how we can facilitate it.

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Figure 3: Vascular oscillations are associated with stronger long-term learning.&amp;nbsp;
Repeated vagus nerve stimulation (VNS) after training induced rhythmic blood-volume changes near the cerebellar flocculus. Mice with larger vascular oscillations tended to perform better on Day 5, suggesting an association between VNS-induced vascular dynamics and a brain environment favorable for long-term learning.
&amp;copy; Junyu U. Chen, Yoko Ikoma, Ko Matsui

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Publication Details
Title:&amp;nbsp;&amp;nbsp; &amp;nbsp;Vagal nerve stimulation induces vascular oscillations and enhances long-term learning
Authors: Junyu U. Chen, Yoko Ikoma, Ko Matsui
Journal: iScience
DOI: https://doi.org/10.1016/j.isci.2026.117413

&amp;nbsp;


Contact
Ko Matsui
Super-network Brain Physiology, Graduate School of Life Sciences
Email: matsui@tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/
&amp;nbsp;

</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Dreams Drain Energy: The REM Sleep Paradox </title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2026-07-28T10:00:00+09:00</updated>
	<summary>
Our brain demands a lot of energy compared to our other organs. However, it can also make do when energy supplies are sparse, flexibly performing information processing using what is available. How the brain resourcefully allocates this limited energy across internal states remains a key question in neuroscience.

&amp;nbsp;

Sleep provides a useful window to the answer of this question. Although sleep is associated with rest, the brain remains highly active. This is especially true during rapid eye movement (REM) sleep, the stage closely linked to dreaming and memory processing. REM sleep is sometimes called &amp;quot;paradoxical sleep&amp;quot; because the body is largely still while the brain shows wake-like activity. Researchers at Tohoku University have now uncovered another paradox within REM sleep: while energy supply to the dreaming brain appears to rise, the energy molecule directly used by neurons falls.

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The findings were published in Communications Biology on July 27, 2026.

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&amp;quot;Ever felt exhausted after a vivid dream?&amp;quot; asks Professor Ko Matsui of Tohoku University. &amp;quot;Sleep may appear peaceful, but the brain is highly active - especially when dreaming. We were intrigued by this paradox, and wanted to look into the scientific basis behind why dreaming is somehow tiring.&amp;quot;

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Figure 1: Brain waves predict local brain blood volume fluctuations during NREM sleep.
Through-skull fluorescence imaging visualizes cerebral blood vessels as dark &amp;quot;shadows,&amp;quot; allowing local brain blood volume dynamics to be estimated (left). During NREM sleep, theta-band brain activity closely matched local brain blood volume changes occurring about 4 seconds later (center). Vascular responses appear to be dynamically adjusted to neuronal activity, supporting on-demand energy supply (right).

&amp;copy;Yusuke Takahashi, Yoko Ikoma, Ko Matsui

&amp;nbsp;

&amp;nbsp;


To get a better understanding, the team kept the mouse skull transparent using a UV-curable resin, allowing them to observe the brain during natural sleep. With wide-field fluorescence imaging, they monitored brain blood volume fluctuations as an indicator of &amp;quot;fuel&amp;quot; supply, neuronal ATP as the energy molecule that powers neurons, and astrocytic pyruvate as a key molecule connecting blood-derived glucose to brain energy metabolism.

&amp;nbsp;

Non-REM sleep is best known for strong neuronal activity in the delta-band frequency, but subtle theta-band fluctuations are also present. The researchers found that these theta-band fluctuations could predict brain blood volume changes several seconds later, suggesting that the sleeping brain adjusts vascular dynamics to ongoing neuronal activity and metabolic demand.

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Figure 2: Brain blood volume dynamics reorganize during the transition to REM sleep.&amp;nbsp;
During NREM sleep, fast local brain blood volume fluctuations propagated from anterior to posterior cortex in about 1 second (left). During the transition to REM sleep, local brain blood volume began to rise about 50 seconds before the ECoG-defined REM onset (center). This increase started in posterior cortex and spread anteriorly over about 15 seconds (right), suggesting that REM sleep is preceded by a posterior-to-anterior metabolic preparation process involving vascular responses. &amp;nbsp;&amp;nbsp;

&amp;copy;Yusuke Takahashi, Yoko Ikoma, Ko Matsui

&amp;nbsp;

&amp;nbsp;

The transition from light non-REM sleep into REM sleep showed a different pattern. About 50 seconds before the classically defined onset of REM sleep, brain blood volume began to rise. This increase started in the posterior cortex and spread forward, suggesting a large-scale metabolic preparation process. After REM sleep began, astrocytic pyruvate also increased, consistent with enhanced substrate availability or elevated astrocytic glycolytic activity. Paradoxically, however, neuronal ATP decreased.

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Figure 3: The brain energy paradox during REM sleep.&amp;nbsp;
During REM sleep, astrocytic pyruvate levels increased along with the increase in local brain blood volume (left). In contrast, when neuronal ATP was measured with a fluorescent sensor, neuronal ATP decreased despite the increase in local brain blood volume (right). These findings suggest that, during REM sleep, increased energy supply does not simply lead to increased neuronal ATP. Instead, energy flow appears to be dynamically reorganized among blood vessels, astrocytes, and neurons. &amp;nbsp;
&amp;copy;Yusuke Takahashi, Yoko Ikoma, Ko Matsui

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Several mechanisms may explain the ATP decrease. Neurons may consume large amounts of ATP during REM sleep to support memory-related synaptic reorganization, hippocampal-cortical communication, or large-scale circuit transitions. Alternatively, metabolic transfer from astrocytes to neurons may be altered, or mitochondrial ATP production may shift.

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The research also points toward a broader principle of biological computation. Unlike conventional computers, animal brains operate under strict metabolic constraints. Rather than distributing energy uniformly, the brain may reroute energy depending on behavioral state, memory demand, and internal needs.

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&amp;quot;Understanding how the brain balances energy supply and consumption may help explain what makes biological intelligence so efficient,&amp;quot; explains lead investigator Yusuke Takahashi. &amp;quot;REM sleep gives us a natural example of how the brain reorganizes its energy economy to support complex internal processing.&amp;quot;

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Sleep is a vital function that can help consolidate memories and keep us mentally sharp the next day. These research findings about energy and sleep are a crucial step forward to helping us understand the science behind sleep, and how a good night&amp;rsquo;s rest is not just important for our bodies &amp;ndash; but our minds too. &amp;nbsp;
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Publication Details&amp;nbsp;
Title:&amp;nbsp;&amp;nbsp;Energy paradox in REM sleep: balancing supply and consumption in brain metabolism
Authors:&amp;nbsp; Yusuke Takahashi, Yoko Ikoma, Ko Matsui
Journal:&amp;nbsp; Communications Biology
DOI: https://doi.org/10.1038/s42003-026-10646-6

&amp;nbsp;

Link

Tohoku University

&amp;nbsp;


Contact&amp;nbsp;
Ko Matsui
Super-network Brain Physiology, Graduate School of Life Sciences
Email: matsui@tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/
&amp;nbsp;

</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Rice Grown on the Moon?</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2026-06-30T13:00:00+09:00</updated>
	<summary>
Securing sustainable food supplies is a key challenge for long-term human exploration and potential habitation of the Moon. The Moon&amp;#39;s soil contains no organic material, and essential plant nitrogen sources like ammonia and nitrate are virtually nonexistent.

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Researchers from Tohoku University and the Japan Aerospace Exploration Agency (JAXA) addressed this obstacle by creating a green, energy-efficient plasma technology capable of synthesizing nitrogen fertilizer from atmospheric air.

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&amp;quot;Our portable plasma device selectively synthesizes dinitrogen pentoxide (N₂O₅) gas from atmospheric air, consuming less than 100 W in the process,&amp;quot; says Toshiro Kaneko, a professor from the Graduate School of Engineering at Tohoku University and co-author of the study. &amp;quot;This plasma-produced gas promptly dissolves in water to generate nitrate (NO₃⁻) with an exceptionally high dissolution efficiency of nearly 100%.&amp;quot;

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Kaneko and his colleagues subsequently evaluated whether the N₂O₅-dissolved water could serve as a local nitrogen fertilizer for cultivating rice seedlings within a lunar regolith simulant.

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Experiments revealed that adding N₂O₅-dissolved water to the lunar regolith simulant successfully neutralized the highly alkaline conditions, lowering its pH from 9.09 to an optimal 6.76. This neutralization released critical mineral nutrients trapped in the regolith, such as calcium, magnesium, and potassium ions, allowing plants to absorb them more readily.

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Schematic illustration of a plasma-based lunar agriculture system. Air is used as a raw material, and plasma generated by electricity from solar cells is utilized to synthesize N₂O₅. The synthesized N₂O₅ is then supplied as a nitrogen fertilizer, enabling the cultivation of crops on the Moon. &amp;copy;Toshiro Kaneko

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Concurrently, the elution of toxic aluminum ions (Al&amp;sup3;⁺) - which normally hinders plant root development - was successfully suppressed. The release of critical mineral and suppression in harmful ones improved rice growth, especially compared to rice grown using pure water alone.

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Beyond acting as a powerful nitrogen fertilizer, the researchers also discovered that the gas helps strengthen plants&amp;#39; immune systems and controls unwanted traits. Spraying N₂O₅ gas directly onto plant leaves activates critical plant hormone pathways that boost resistance and immunity. Gas exposure also suppressed stem and internode elongation, which prevents legginess, something essential for managing crop structures under the low-gravity conditions of space environments.

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Rice growth on lunar regolith simulant with N₂O₅ dissolved water. Compared with the water-only control, plants treated with the N₂O₅ solution exhibited markedly enhanced growth three months after sowing. Furthermore, heading was observed four months after sowing, indicating that the N₂O₅ solution is effective as a nitrogen fertilizer. &amp;copy;Toshiro Kaneko

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Kaneko stresses that whilst the technology is ideally suited for lunar farms, it can also help reduce environmental burdens in agriculture here on earth.

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&amp;quot;The process of producing this fertilizer operates entirely on electricity and low power, completely decoupling nitrogen fixation from fossil fuels, making the technology suitable for sustainable crop production on the Moon and here on Earth.&amp;quot;

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Details of this breakthrough technology were published in the journal npj Microgravity on May 2, 2026.

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Publication Details:
Title: Plasma nitrogen fixation for future lunar agriculture

Authors: Toshiro Kaneko, Shota Sasaki, Daiki Suzuki, Hayato Ohkuma, Atsushi Higashitani

Journal: npj Microgravity

DOI: 10.1038/s41526-026-00602-3
&amp;nbsp;

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Link

Tohoku University

School of Engineering, Tohoku University

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Contact

Toshiro Kaneko
Research Center for Space Cross-Tech / The Graduate School of Engineering, Tohoku University
Email: kaneko(at)tohoku.ac.jp
Website:https://researchmap.jp/read0191501?lang=en

&amp;nbsp;

&amp;nbsp;

Atsushi Higashitani
Research Center for Space Cross-Tech / Graduate School of Life Sciences, Tohoku University
Email: atsushi.higashitani.e7(at)tohoku.ac.jp



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</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Fish &quot;Steals&quot; Glowing Protein: Genome Sequencing Proves Unique Survival Strategy</title>
	<link rel="alternate" type="text/html" href="https://www.tohoku.ac.jp/en/press/fish_steals_glowing_protein.html" />
	<updated>2026-04-09T15:00:00+09:00</updated>
	<summary></summary>
	<id>https://www.tohoku.ac.jp/en/press/fish_steals_glowing_protein.html</id>
</entry>	<entry>
	<title>The Flexible Brain: How Circuit Excitability and Plasticity Shift Across the Day</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2025-11-11T10:00:00+09:00</updated>
	<summary>
Our brains do not react in a fixed, mechanical way like electronic circuits. Even if we see the same scene every day on our commute to work, what we feel&amp;mdash;and whether it leaves a lasting impression&amp;mdash;depends on our internal state at that moment. For example, your commute may be a blur if you&amp;rsquo;re too tired to pay attention to your surroundings.

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The 24-hour cycle that humans naturally follow is one of the factors that shapes the brain&amp;rsquo;s internal environment. These internal physiological cycles arise from the interplay between the body&amp;rsquo;s intrinsic circadian clock and the external light-dark cycle that synchronizes it. Yet how such daily fluctuations influence brain chemistry and affect neuronal excitability and plasticity has remained largely unknown. Now, researchers at Tohoku University have directly observed time-of-day-dependent changes in neural signal responses in the brains of nocturnal rats.

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The findings were published in Neuroscience Research on October 31, 2025.


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Figure 1. &amp;nbsp;Nocturnal rats are active at night and accumulate fatigue toward dawn. Using optogenetic stimulation of cortical neurons and simultaneous local field potential (LFP) recordings, the study revealed that neural responses were weaker before sunrise and stronger before sunset, indicating a roughly 24-hour rhythm in cortical activity. &amp;copy; Yuki Donen, Yoko Ikoma, Ko Matsui

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Using optogenetics, the team activated neurons in the visual cortexes of rats and recorded the resulting electrical activity. This approach allowed precise quantification of neural responsiveness. They found that identical neural stimuli evoked different responses depending on the time of day. Neural activity was reduced at sunrise and enhanced at sunset. Since rats are nocturnal, sunrise represents the period after a night of activity when they are preparing to sleep.

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To explore the underlying mechanism explaining why this was occurring, the researchers looked at adenosine, a neuromodulator that accumulates during wakefulness and makes us feel sleepy. When the researchers blocked the action of adenosine, neural activity at sunrise became disinhibited and enhanced , showing that adenosine helps regulate cortical excitability across the day.



&amp;quot;Neural excitability is not constant; it depends on the brain&amp;#39;s internal state,&amp;quot; says Professor Ko Matsui of Tohoku University. &amp;quot;Our results show that even identical neurons can respond differently depending on the time of day, governed by molecules like adenosine that link metabolism, sleep, and neuronal signaling.

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The team also examined whether the brain&amp;rsquo;s capacity for long-term potentiation (LTP), a cellular basis of learning and memory, changes with time of day. This represents the brain&amp;rsquo;s potential for metaplasticity (the brain&amp;rsquo;s ability to adjust how easily its networks change). Remarkably, repetitive optical stimulation induced LTP-like enhancement at sunrise, but not at sunset. This was unexpected, as it suggests that although sleep pressure and fatigue peak at sunrise, the brain&amp;rsquo;s metaplastic potential is heightened at this time. These findings indicate that the brain&amp;rsquo;s ability to reorganize itself follows a daily rhythm, with specific periods more favorable for learning and adaptation.

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&amp;quot;These results imply that our brains have temporal windows that favor adaptability,&amp;quot; explains lead investigator Yuki Donen. &amp;quot;Knowing when the brain is most receptive to changing could help optimize training, rehabilitation, and stimulation-based therapies.

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In humans, who are mainly active during daylight hours, the capacity for learning and memory formation may peak during the twilight period approaching sunset. In other words, the best time to study or learn something new may be before bedtime.

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The study reveals how daily rhythms fine-tune the balance between excitability and plasticity in the cortex. Because adenosine levels and sleep pressure follow circadian patterns, this mechanism may synchronize brain adaptability with behavioral cycles such as rest and activity. The research provides new insight into how the brain coordinates energy use, neural signaling, and learning capacity across the day.

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Figure 2. Recording daily rhythms of cortical neural signals. (A) In Thy1-ChR2 rats, cortical neurons were optogenetically activated, and local field potentials (LFPs) were recorded in the visual cortex. (B) The slope of the third negative LFP phase was larger at sunset than at sunrise, indicating stronger responses in the evening. (C) Averaged signals over three days showed a ~24-hour sinusoidal pattern synchronized with the light-dark cycle. &amp;copy; Yuki Donen, Yoko Ikoma, Ko Matsui
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&amp;lt;Publication Details&amp;gt;&amp;nbsp;
Title:&amp;nbsp;&amp;nbsp; &amp;nbsp;Diurnal modulation of optogenetically evoked neural signals
Authors: Yuki Donen, Yoko Ikoma, Ko Matsui
Journal: Neuroscience Research
DOI:&amp;nbsp;&amp;nbsp; &amp;nbsp;https://doi.org/10.1016/j.neures.2025.104981


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&amp;nbsp;

Link

Tohoku University

&amp;nbsp;

Contact:

Ko Matsui,
Super-network Brain Physiology, Graduate School of Life Sciences, Tohoku University
Email: matsui@med.tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/

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</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Revealing Brain Energy Dynamics: Decoding the Response to Epileptic Seizures</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2025-03-24T14:00:00+09:00</updated>
	<summary>Cell survival depends on the energy molecule adenosine triphosphate (ATP) &amp;ndash; it&amp;rsquo;s like the fuel that keeps our brain running. Intracellular ATP levels are thought to remain constant, given its importance. To maintain this stability, the brain strikes a delicate balance between metabolic energy supply and how much energy our brain is using (neuronal activity).

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Purposely causing an imbalance in this carefully regulated system and observing the effects can reveal surprising insights. Researchers from Tohoku University challenged the mouse brain with a metabolic load induced by epileptic seizures, and observed fluctuations in blood volume, astrocytic pyruvate, and neuronal ATP. They found that a single epileptic seizure could greatly reduce ATP. This finding may help redefine our understanding of brain energy dynamics, and how it impacts individuals with epilepsy.

&amp;nbsp;

The findings were published in the Journal of Neurochemistry on March 20, 2025.
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&amp;lt;Figure 1&amp;gt;

During an epileptic seizure, pyruvate levels in astrocytes increased, while ATP levels in neurons decreased. The experiments suggest that the transfer of metabolic energy molecule transfer may be temporarily disrupted during an epileptic episode. &amp;copy; Kota Furukawa, Ko Matsui

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An optical fiber inserted into the hippocampus of mice allowed the researchers to visualize fluorescent ATP, or pyruvate sensors in neurons or astrocytes, respectively, to measure fluctuations in these metabolites. A train of electrical stimulation in the hippocampus induced a hyperactive response resembling epileptic seizures. In response, ATP levels in neurons decreased, while pyruvate levels in astrocytes increased.&amp;nbsp;

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The brain accounts for 2% of body mass but consumes 20% of the body&amp;rsquo;s total glucose. Although glucose and oxygen are supplied to the brain through blood vessels, neurons don&amp;rsquo;t directly contact these vessels&amp;mdash;astrocytes do. Astrocytes take up glucose, convert it into pyruvate, and then into lactate. The lactate is released and later taken up by neurons, which convert it back into pyruvate to produce ATP. During the induced epileptic seizure, it is possible that this lactate shuttle was temporarily shut down, causing an accumulation of excess pyruvate in astrocytes and a decrease in neuronal ATP.&amp;nbsp;

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The same stimulation leads to varying lengths of neuronal hyperactivity (after discharges; ADs). Although a prolonged AD would typically consume more energy, they found that the reduction in neuronal ATP remained the same. Interestingly, the reduction in neuronal ATP levels decreased as epilepsy developed, while the local blood volume increased. This rise in metabolic energy supply may partially compensate for the loss of ATP in neurons.

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&amp;lt;Figure 2&amp;gt;

Despite the same intensity of hippocampal stimulation, the duration of epileptic neuronal hyperactivity varied in the same animals. However, the reduction in intracellular neuronal ATP remained constant, suggesting that the varying degree of ATP consumption during neuronal hyperactivity has little impact on net ATP levels. &amp;copy; Kota Furukawa, Ko Matsui

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These results suggest that the supply of energy molecules from blood vessels and astrocytes may play a much more significant role in determining ATP levels than previously thought.

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&amp;ldquo;We believe this could change how we understand energy management in the brain,&amp;rdquo; says Professor Ko Matsui of Tohoku University. &amp;ldquo;The key to understanding the brain&amp;rsquo;s super energy-saving, information-processing capabilities may lie in studying the neuron-metabolic system.&amp;rdquo;

&amp;nbsp;

Lead investigator Kota Furukawa believes understanding brain energy dynamics could be the key to treating brain diseases. &amp;ldquo;This may just be a glimpse of how astrocytes and blood vessels affect epilepsy pathology,&amp;rdquo; Furukawa explains. &amp;ldquo;An intricate neuron-metabolic system provides stable energy for daily information processing. A glitch in this system could underlie numerous brain diseases - not just epilepsy, but also mental illnesses.&amp;rdquo;
&amp;nbsp;



&amp;lt;Figure 3&amp;gt;&amp;nbsp;
Caption: With repeated hippocampal stimulation, seizures intensify. As seizures intensify, neuronal ATP decreases, and local blood volume increases. &amp;copy; Kota Furukawa, Ko Matsui

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&amp;nbsp;

&amp;lt;Link&amp;gt;

TOHOKU University

&amp;nbsp;

&amp;nbsp;

&amp;lt;Publication Details&amp;gt;&amp;nbsp;
Title:&amp;nbsp;Dynamics of neuronal and astrocytic energy molecules in epilepsy
Authors: Kota Furukawa, Yoko Ikoma, Yusuke Niino, Yuichi Hiraoka, Kohichi Tanaka, Atsushi Miyawaki, Johannes Hirrlinger, Ko Matsui
Journal: Journal of Neurochemistry
DOI:&amp;nbsp;https://doi.org/10.1111/jnc.70044

&amp;nbsp;


&amp;lt;Contact&amp;gt;&amp;nbsp;
Ko Matsui
Super-network Brain Physiology, Graduate School of Life Sciences
Email: matsui@tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/
&amp;nbsp;

</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Combining Software Tools Creates Higher Standards in Species Distribution Modeling</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2025-02-17T15:30:00+09:00</updated>
	<summary>In an effort to monitor biodiversity trends, greater efforts are being made worldwide to assess biodiversity patterns over large scales. To do this, scientists rely on species distribution models (SDMs), which make predictions of species&amp;#39; geographical ranges based on species data and environmental variables. With these models, scientists can make predictions of habitat suitability under different global change scenarios and tailor management and conservation efforts accordingly.

&amp;nbsp;


The international Group on Earth Observations Biodiversity Observation Network (GEO BON), which pools resources and researchers from across the globe, has recently conceptualized &amp;quot;essential biodiversity variables&amp;quot; to standardize the collection and coordination of biodiversity data, and many of these variables can be made with SDMs. Most cutting-edge SDM techniques are implemented in R, a popular statistical programming language, and many new tools have surfaced in recent years in the form of R packages. But researchers often get overwhelmed by the plethora of R packages out there, wondering, &amp;#39;Which one should I use for my research?&amp;#39;

&amp;nbsp;

In a new paper, Jamie M. Kass, associate professor and head of the Macroecology Lab at Tohoku University&amp;#39;s Graduate School of Life Sciences, argues that SDM workflows benefit highly from use of multiple packages. Kass, who has helped develop several R packages for SDMs - including ENMeval (which fine-tunes machine-learning SDMs) and wallace (a user-friendly application for SDM workflows) - teamed up with experts worldwide to create a guide for using multiple R package tools effectively and in innovative ways.

&amp;nbsp;


The team introduced a new R meta-package called sdmverse, which catalogs R packages for SDMs by the functions they offer and provides visualization features to help researchers understand how they relate to each other. They also contributed three real-world case studies in R showing how combining tools can broaden the diversity of analyses possible and help meet more methodological standards for the field.

&amp;nbsp;


&amp;quot;New tools help science move forward, but they can also be overwhelming,&amp;quot; says Kass. &amp;quot;We wanted to create a roadmap that shows researchers how to navigate these tools and use them together for better biodiversity modeling.&amp;quot;

&amp;nbsp;

By following their approach, researchers can improve accuracy, tackle a wider range of questions, and contribute to stronger biodiversity assessments worldwide. As environmental challenges grow, using the best available tools--together - will be essential for tracking trends in biodiversity and protecting nature.

&amp;nbsp;



These plots, generated with the new sdmverse R package, show functionalities provided by R packages for species distribution modeling and the relationships between them. &amp;copy;Ecography

&amp;nbsp;

&amp;nbsp;

Publication Details:
Title: Achieving higher standards in species distribution modeling by leveraging the diversity of available software
Authors: Jamie M. Kass, Adam B. Smith, Dan L. Warren, Sergio Vignali, Sylvain Schmitt, Matthew E. Aiello-Lammens, Eduardo Arl&amp;eacute;, Ana M&amp;aacute;rcia Barbosa, Olivier Broennimann, Marlon E. Cobos, Maya Gu&amp;eacute;guen, Antoine Guisan, Cory Merow, Babak Naimi, Michael P. Nobis, Ian Ondo, Luis Osorio-Olvera, Hannah L. Owens, Gonzalo E. Pinilla-Buitrago, Andrea S&amp;aacute;nchez-Tapia, Wilfried Thuiller, Roozbeh Valavi, Santiago Jos&amp;eacute; El&amp;iacute;as Velazco, Alexander Zizka, Damaris Zurell
Journal: Ecography
DOI: 10.1111/ecog.07346

&amp;nbsp;

Press release

Tohoku University

&amp;nbsp;

Contact:
Jamie M Kass,
Email: kass(at)tohoku.ac.jp
Website: https://macroecolab.github.io/
</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>New Smart Agriculture Technology for Monitoring Plants</title>
	<link rel="alternate" type="text/html" href="https://www.tohoku.ac.jp/en/press/new_smart_agriculture_technology_for_monitoring_plants.html" />
	<updated>2024-11-27T08:30:00+09:00</updated>
	<summary></summary>
	<id>https://www.tohoku.ac.jp/en/press/new_smart_agriculture_technology_for_monitoring_plants.html</id>
</entry>	<entry>
	<title>How studying fruit flies can help us understand congenital defects</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2024-11-19T10:00:00+09:00</updated>
	<summary>
When complex multicellular organisms grow and develop, their tissues must undergo remodeling. As new cells begin to proliferate, old cells must be removed to make room and maintain tissue balance and function. One example of this is in the Drosophila (fruit fly) abdominal epithelium during metamorphosis, where larval epidermal cells (LECs) are replaced by histoblasts, which are the precursors of the adult cells. In a recent article published in PLOS Biology, a team of researchers from Tohoku University, led by researchers at Osaka University, describe new molecular details behind how LEC removal is carefully coordinated.

&amp;nbsp;


During Drosophila development, LECs slowly begin to undergo apoptosis. In the late phase, the LECs are rapidly eliminated, with full replacement by the histoblasts. Although the importance of this process was well-defined, the specific mechanisms controlling it were unclear. The team became interested in how LEC removal is affected by endocytosis, the process through which substances are ingested or taken up by cells.

&amp;quot;Our group recently published a study showing that reduced endocytic activity can stimulate certain molecular events that result in LEC apoptosis,&amp;rdquo; says Kevin Yuswan (Tohoku University), lead author of the study. &amp;ldquo;This increased our interest in the epidermal growth factor receptor (EGFR) pathway because previous work indicated that it may be regulated by endocytosis.&amp;quot;

&amp;nbsp;


Using various molecular and cellular methods, the team found that the accelerated LEC apoptosis occurring in late Drosophila development involves a mode switching, with isolated single-cell apoptosis transitioning to more clustered apoptosis. Interestingly, genetically knocking down EGFR expression levels resulted in widespread LEC elimination earlier in the developmental process, while overexpressing EGFR led to reduced LEC elimination.

&amp;nbsp;








&amp;nbsp;



&amp;lt;Figure&amp;gt;&amp;nbsp;

In the early phase of epidermal tissue remodeling precursor cells of adult epidermis called histoblasts proliferate only slowly (top, pink) and cells of larval epidermis should not proliferate rapidly (green). The cells that undergo programed cell death (apoptosis) interact with surrounding cells to prevent premature cell death through the activation of the EGFR/ERK signaling pathway (low and high EGFR/ERK signaling levels are indicated in dark and light colors, respectively). As the tissue remodeling progresses, histoblasts proliferate more rapidly, and the removal of larval epidermal cells has to be accelerated. During this late phase, the up-regulation of EGFR/ERK signaling in the surrounding cells of a dying cells does not occur thereby a group of cells die together. As a consequence, the removal of larval epidermal cells is accelerated.&amp;nbsp;&amp;copy;Kevin Yuswan

&amp;nbsp;

&amp;nbsp;


&amp;quot;Further work indicated that decreased activity of extracellular-signal regulated kinase (ERK), a downstream molecule of EGFR, is controlled by the reduced endocytic activity,&amp;rdquo; explains Daiki Umetsu (Osaka University), senior author of the study. &amp;ldquo;It also became clear that ERK activity is critical for the apoptotic mode switching.

&amp;nbsp;


Specifically, the normal LECs that surround one apoptotic LEC display transiently increased ERK activity, which blocks clustered cell death. However, the reduced endocytic activity prevents this higher ERK activation, causing LEC apoptosis to start occurring in clusters that ultimately results in an accelerated cell elimination rate.

&amp;nbsp;


&amp;quot;The field has generally believed that clustered apoptosis poses disadvantages to the organism,&amp;rdquo; says Yuswan, &amp;ldquo;Our data contrast this hypothesis by suggesting that clustered apoptosis is required for proper and efficient tissue growth.&amp;rdquo;

&amp;nbsp;


While providing molecular details of tissue remodeling in Drosophila, this study also has wider health implications. This better mechanistic understanding of apoptosis regulation during tissue growth will help determine how abnormal cell death can lead to congenital defects during development.

&amp;nbsp;


These findings were published in PLOS Biology on October 14, 2024.


&amp;nbsp;

&amp;nbsp;

&amp;lt;Publication Details&amp;gt;&amp;nbsp;
Title: Reduction of endocytosis and EGFR signaling is associated with the switch from isolated to clustered apoptosis during epithelial tissue remodeling in Drosophila
Authors: Kevin Yuswan, Xiaofei Sun, Erina Kuranaga, Daiki Umetsu
Journal: PLOS Biology
DOI:&amp;nbsp;&amp;nbsp;https://doi.org/10.1371/journal.pbio.3002823

&amp;nbsp;

Press release&amp;nbsp;

Tohoku University
&amp;nbsp;

Press release in Japanese
&amp;lt;link: https://www.lifesci.tohoku.ac.jp/date/detail---id-52252.html&amp;gt;

&amp;nbsp;

&amp;lt;Contact&amp;gt;&amp;nbsp;
Erina Kuranaga
Graduate School of Life Sciences
Email: erina.kuranaga.d1(at)tohoku.ac.jp
Website:&amp;nbsp;&amp;nbsp;http://www.biology.tohoku.ac.jp/lab-www/kuranaga_lab/index.html
&amp;nbsp;











</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Saying Goodbye to Traumatic Memories: Astrocytic Manipulation of the Fate of Memory</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2024-11-11T14:00:00+09:00</updated>
	<summary>One of the most powerful assets of the brain is that it can store information as memories, allowing us to learn from our mistakes. However, some memories remain vivid, while others become forgotten. Unlike computers, our brains appear to filter which memories are salient enough to store.&amp;nbsp;
&amp;nbsp;

Researchers from Tohoku University discovered that part of the memory selection process depends on the function of astrocytes, a special type of cell that surrounds neurons in the brain. They showed that artificially acidifying the astrocytes did not affect short-term memory but prevented memories from being remembered long-term.
&amp;nbsp;

The findings were detailed in the journal GLIA on November 4, 2024.

The researchers implemented a technique called &amp;ldquo;optogenetics&amp;quot; to manipulate the astrocytes by shining light onto them through optical fibers inserted in the mice&amp;#39;s brains. This enabled researchers to directly stimulate and either acidify or alkalinize the astrocytes in that area. They focused on the functions of astrocytes in the amygdala, a brain region known to be crucial for regulating emotion and fear.&amp;nbsp;
&amp;nbsp;

A mild electrical shock was delivered to mice in an experiment chamber. When placed back in the same chamber, the mice remembered the shock and froze as a natural response. However, the mice who had their astrocytes acidified immediately after the mild shock were able to temporarily hold onto the fear memory, but they forgot it by the next day. This shows that acidifying the astrocytes did not affect short-term memory but prevented the memories from being remembered long-term.&amp;nbsp;
&amp;nbsp;

&amp;nbsp;



&amp;lt;Figure 1&amp;gt;&amp;nbsp;
Caption: Selective suppression of long-term memory formation through ChR2 photoactivation of amygdala astrocytes. The experiments suggest the presence of parallel processes governing short-term and long-term memory formation, respectively.
&amp;nbsp;&amp;copy;Hiroki Yamao, Ko Matsui

&amp;nbsp;

&amp;nbsp;


A different effect was seen for mice who had their astrocytes alkalinized. When tested three weeks later, control mice typically showed signs of forgetting, demonstrated by a decrease in freezing responses. However, mice whose astrocytes were alkalinized immediately after a strong shock still displayed strong fear responses even after three weeks. This suggests that astrocytes play a key role in determining whether memories are erased or preserved for a long time, immediately after a traumatic event.
&amp;nbsp;

While it is generally believed that memories are formed in a continuous process whereby short-term memories gradually solidify and become long-term memories, this research suggests they may actually develop in parallel. &amp;quot;We believe that this could change the way we understand memory formation,&amp;quot; says Professor Ko Matsui of the Super-network Brain Physiology lab at Tohoku University, who led the research. He added, &amp;quot;The effect of astrocytes on memory likely also depends on various contexts, including mental, social, or environmental factors.&amp;quot;
&amp;nbsp;

Lead investigator Hiroki Yamao believes astrocytes could hold the key to understanding emotional changes and memory formation. &amp;quot;This may be just a glimpse of how astrocytes affect emotional information processing,&amp;quot; Yamao explains. &amp;quot;Our next goal is to uncover the mechanisms by which astrocytes regulate emotional memory. Understanding these processes could pave the way for therapies that prevent traumatic memories from forming, offering a valuable approach to treating disorders like post-traumatic stress disorder (PTSD) by intervening in memory formation.&amp;quot;

&amp;nbsp;

&amp;nbsp;



&amp;lt;Figure 2&amp;gt;&amp;nbsp;
Caption: Mice inherently possess a selective filtering mechanism that enhances the memory of intense experiences; however, this filtering function was inhibited by ArchT photoactivation of astrocytes in the amygdala. Additionally, the natural forgetting process over three weeks was suppressed by the light stimulation of ArchT-expressing astrocytes. &amp;copy; Hiroki Yamao, Ko Matsui
&amp;nbsp;

&amp;nbsp;



&amp;lt;Figure 3&amp;gt;&amp;nbsp;
Caption: Astrocytes are capable of triggering fear. Astrocyte ChR2 photoactivation alone induced freezing responses akin to those observed after receiving an electric foot shock. In contrast, astrocyte ArchT photoactivation suppressed the freezing responses following a footshock. &amp;copy; Hiroki Yamao, Ko Matsui
&amp;nbsp;

&amp;nbsp;


&amp;lt;Publication Details&amp;gt;&amp;nbsp;
Title:&amp;nbsp;&amp;nbsp; &amp;nbsp;Astrocytic determinant of the fate of long-term memory
Authors: Hiroki Yamao, Ko Matsui
Journal: GLIA
DOI:&amp;nbsp;&amp;nbsp;https://doi.org/10.1002/glia.24636
&amp;nbsp;

Press release&amp;nbsp;

Tohoku University

Tohoku University School of Medicine
&amp;nbsp;

Press release in Japanese
&amp;lt;link: https://www.lifesci.tohoku.ac.jp/research/results/detail---id-52280.html &amp;gt;
&amp;nbsp;

&amp;lt;Contact&amp;gt;&amp;nbsp;
Ko Matsui
Super-network Brain Physiology, Graduate School of Life Sciences
Email: matsui@tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/
&amp;nbsp;



</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Coordinating Blood Vessel Activity Might be Associated with Better Brain Performance</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2024-04-26T11:00:00+09:00</updated>
	<summary>
Compared with computers, the brain can perform computations with a very low net energy supply. Yet our understanding surrounding how the biological brain manages energy is still incomplete. What is known, however, is that the dilation and constriction cycles of blood vessels, or vasomotion, spontaneously occur in the brain, a process that likely contributes to enhancing the circulation of energetic nutrients and clearing wasteful materials.

&amp;nbsp;

Now, researchers from Tohoku University have developed a method that easily observes and monitors blood vessel dynamics in the mouse brain. This can be done either through the intact skull of a mouse, or deep into the brain using an implanted optical fiber.

&amp;nbsp;

The findings were detailed in the journal, eLife, on April 17, 2024.

&amp;nbsp;

Since it has been reported that sensory stimuli can cause dilation of blood vessels or hyperemia, researchers sought to induce vasomotion via presenting mice with visual stimuli. What they discovered was when a mouse was shown a horizontally moving stripe pattern that changed direction every 2 to 3 seconds, it caused a reaction in the mouse&amp;#39;s blood vessels that matched the pattern&amp;#39;s speed.

&amp;nbsp;

Mice were presented with 15-minute visual training sessions interleaved with 1-hour resting periods for 4 times per day. With such spaced training, the amplitude of the synchronized vasomotion gradually increased. Interestingly, the visually induced vasomotion was not confined to the area of the cerebral cortex responsible for visual information processing. In other words, synchronized vasomotion spread throughout the whole brain.

&amp;nbsp;

&amp;ldquo;Synchronized vascular motion can be entrained with slowly oscillating visual stimuli,&amp;rdquo; says Professor Ko Matsui of the Super-network Brain Physiology lab at Tohoku University, who led the research. &amp;ldquo;Such enhancement of circulation mechanisms may benefit the information processing capacity of the brain.&amp;rdquo;

&amp;nbsp;

While it&amp;#39;s long been known that changes in neuron connections support learning and memory, the plasticity of vasomotion hasn&amp;#39;t been described before. Matsui and his colleagues found that a specific visual pattern makes the eyes move more, and this eye movement improvement depends on changes in the brain&amp;#39;s cerebellum. The researchers also observed that blood vessel activity in the cerebellum synchronized with this optokinetic motor learning.

&amp;nbsp;

Lead study investigator, Daichi Sasaki, believes that synchronized vasomotion, which efficiently delivers oxygen and glucose, could improve learning abilities. He states, &amp;quot;Our next step is to explore the advantages of vasomotion synchronization. It might help clear waste like amyloid beta, potentially delaying or preventing dementia. Stroke recovery could also benefit from better energy supply and waste removal. Additionally, synchronized vasomotion might even enhance intelligence beyond our natural capabilities.&amp;quot;

&amp;nbsp;



When mice were presented with a horizontal slow oscillation of vertical stripe patterns, vascular dilation and constriction movements that were temporal frequency-locked to the visual stimulus were observed. Such frequency-locked vasomotion was induced not only in the visual cortex but throughout the whole brain. Based on this, vasomotion could increase the efficiency of energy delivery into the brain and also facilitate the clearance of waste materials. Therefore, the researchers hypothesize vasomotion training may result in brain performance enhancement and the treatment of brain disorders.&amp;nbsp;&amp;copy; Daichi Sasaki, Ko Matsui

&amp;nbsp;

&amp;nbsp;



Vasomotion induced by horizontally oscillating visual stimuli was amplified with training and synchronized throughout the whole brain. &amp;nbsp;&amp;nbsp;&amp;copy; Daichi Sasaki, Ko Matsui

&amp;nbsp;

&amp;nbsp;



&amp;nbsp;

Parallel occurrence of the learning of horizontal optokinetic response (HOKR) and vasomotion entrainment.&amp;nbsp;

&amp;nbsp;&amp;copy; Daichi Sasaki, Ko Matsui

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

Publication Details:

Title :&amp;nbsp;Plastic vasomotion entrainment
Authors :&amp;nbsp;Daichi Sasaki, Ken Imai, Yoko Ikoma, Ko Matsui
Journal :&amp;nbsp;eLife
DOI :&amp;nbsp;https://doi.org/10.7554/eLife.93721.3
&amp;nbsp;

Link

Tohoku University

&amp;nbsp;

Contact:
Ko Matsui,
Super-network Brain Physiology, Graduate School of Life Sciences,
Tohoku University
Email: matsui@med.tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/

&amp;nbsp;


&amp;nbsp;

</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Glial Hyper-drive for Triggering Epileptic Seizures</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2024-04-19T11:00:00+09:00</updated>
	<summary>
Epilepsy, where patients suffer from unexpected seizures, affects roughly 1% of the population. These seizures often involve repetitive and excessive neuronal firing, with the trigger behind this still poorly understood.&amp;nbsp;

&amp;nbsp;

Now, researchers at Tohoku University have monitored astrocyte activity using fluorescence calcium sensors, discovering that astrocyte activity starts approximately 20 seconds before the onset of epileptic neuronal hyperactivity. This suggests that astrocytes play a significant part in triggering epileptic seizures, facilitating the hyper-drive of the neural circuit.

&amp;nbsp;

The findings were detailed in the journal Glia on April 9, 2024.

&amp;nbsp;

Astrocytes are non-neuronal glial cells that occupy almost half of the brain. They have been shown to control the local ionic and metabotropic environment in the brain. Yet, since they do not exhibit electrical activity that can be easily monitored, their role in the function of the brain has largely been neglected. Fluorescence sensor proteins are changing this, revealing more about the mesmerizing activity of astrocytes.
&amp;nbsp;
&amp;ldquo;Astrocytes appear to have a determinant role in controlling the state of neuronal activity and synaptic plasticity both in physiological and pathophysiological situations,&amp;rdquo; says Professor Ko Matsui of the Super-network Brain Physiology lab at Tohoku University, who led the research. &amp;ldquo;Therefore, astrocytes could be considered as a new therapeutic target for epilepsy treatment.&amp;rdquo;

&amp;nbsp;

When brain tissue makes contact with metals such as copper, it is known to induce inflammation that leads to acute symptomatic seizures, which occurs a few times per day in mice. Matsui and his team observed these events, where they discovered that astrocyte activity may be the trigger for neuronal hyperactivity. Astrocytes can also be activated by low-amplitude direct current stimulation. The researchers noticed that such a stimulation induced a robust increase in the astrocyte calcium, which was followed by an epileptic neuronal hyperactivity episode. When the metabolic activity of the astrocytes was blocked by applying fluorocitrate, the magnitude of the epileptic neuronal hyperactivity was significantly reduced. These all point to the fact that astrocytes have the potential to control neuronal activity.

&amp;nbsp;

Lead study investigator Shun Araki emphasizes that with appropriate guidance, astrocytes&amp;#39; functions could be harnessed to address a range of neurological conditions. This includes not only epilepsy but also potentially enhancing cognitive abilities beyond natural limitations.&amp;nbsp;
&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;



Glial hyper-drive for neuronal control. An optical fiber was implanted into the hippocampus of the brain of the transgenic mouse, which expressed fluorescence calcium sensor protein in astrocytes of the glial cell population. Astrocytes were considered to be silent cells with a minor role in the functioning of the brain. However, with the optical monitoring techniques, the abundance of astrocyte activity is starting to become realized. The researchers were able to capture rare moments of epileptic neuronal hyperactivity using a model of acute symptomatic seizures in mice. The astrocyte calcium elevation started as early as approximately 20 seconds earlier than the neuronal hyperactivity. This suggests that astrocytes trigger the hyper-drive of the neural circuit.&amp;nbsp;&amp;copy; Ko Matsui

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;



Astrocyte activity precedes the onset of epileptic neuronal hyperactivity episodes. (A) With cytosolic calcium ion increase, excitatory actions from astrocytes to neurons are likely to be initiated. These excitatory actions induce a reciprocal excitatory network between neurons, which results in neural circuit oscillations. (B) Calcium in astrocytes started to rise as early as 20 seconds before the onset of neuronal hyperactivity. Neuron-to-astrocyte action is also triggered and reciprocal interactions of neurons and astrocytes occur throughout the epileptic episode. &amp;copy; Ko Matsui

&amp;nbsp;

&amp;nbsp;



&amp;nbsp;

Astrocytes hyper-drive neuronal activity. (A) Passing low amplitude direct current (DC) stimulation resulted in a robust increase in the astrocyte calcium. Several seconds following the astrocyte activation, epileptic neuronal hyperactivity was initiated. (B) Copper implantation in the hippocampus induced acute symptomatic seizures. Fluorocitrate is preferentially taken up into astrocytes and suppresses their metabolic activity. Even in the presence of fluorocitrate, epileptic episodes were observed; however, the magnitude of the hyperactivity was significantly reduced. These results suggest that actions originating from the astrocytes induce epileptic neuronal hyperactivity. &amp;copy; Ko Matsui

&amp;nbsp;

Publication Details:

Title:&amp;nbsp;Astrocyte switch to the hyperactive mode
Authors:&amp;nbsp;Shun Araki, Ichinosuke Onishi, Yoko Ikoma, Ko Matsui
Journal:&amp;nbsp;Glia
DOI:&amp;nbsp;https://doi.org/10.1002/glia.24537

&amp;nbsp;

Link

Tohoku University

Tohoku University School of Medicine

&amp;nbsp;

Contact:

Ko Matsui,
Super-network Brain Physiology, Graduate School of Life Sciences,
Tohoku University
Email: matsui@med.tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Habenular Astrocytes Tuning Anxiety with the ‘Marble Blues’</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2024-02-15T15:00:00+09:00</updated>
	<summary>Anxiety is often attributed to an unconscious assessment of the environment and detection of potential danger. Whilst moderate anxiety is therefore advantageous for survival, excessive anxiety can lead to psychiatric disorders.

&amp;nbsp;

&amp;nbsp;

Now, researchers at Tohoku University have shed light on the intricate interactions between neurons and astrocytes within the habenula, a region of the brain associated with emotional processing. By subjecting mice to a scenario involving a floor scattered with marbles, the researchers observed behavioral responses indicative of anxiety.

&amp;nbsp;

&amp;nbsp;

The findings were detailed in the journal, Neuroscience Research, on February 10, 2024.

&amp;nbsp;

&amp;nbsp;

The habenula are a pair of small nuclei located above the thalamus. It is one of the few brain regions that controls both dopaminergic and serotonergic systems. As these neuromodulators play essential roles in a wide range of motivational and cognitive functions, habenula neuronal circuits are potentially relevant to controlling anxiety.

&amp;nbsp;

&amp;nbsp;

&amp;ldquo;Anxiety may appear to be an irrational emotion having only negative impacts on our life,&amp;rdquo; says Professor Ko Matsui of the Super-network Brain Physiology lab at Tohoku University, who led the research. &amp;ldquo;However, well-tuned anxiety is a guide provided by our unconsciousness which allows us to navigate the hidden dangers. Such tuning may be accomplished by the actions of the habenula.&amp;rdquo;

&amp;nbsp;

&amp;nbsp;

Mice perceive smooth glass marbles as potentially harmful objects due to their unfamiliarity. Mice tend to bury marbles in saw dust bedding to keep these uncomfortable objects out of sight. Here, the researchers created a chamber filled with marbles to create an inescapable, maximum anxiety environment.

&amp;nbsp;

&amp;nbsp;

They noticed increased neuronal activity in the theta band (5 to 10 Hz) frequency, an increase in local brain blood volume, and acidification occurring in the astrocytes of the habenula when the mice were placed in the all-marble cage. When the habenular astrocytes were artificially alkalized to counter the acidification, the theta band neuronal activity diminished. When the mice were allowed to choose between the brightly lit all-marble cage and a dark and comfortable cage, the mice naturally chose to stay in the dark cage. However, when the habenular astrocytes were optogenetically alkalized, the mice ventured more into the bright cage.

&amp;nbsp;

&amp;nbsp;

Astrocytes are non-neuronal cells that occupy approximately half of the brain. They have been shown to control the local ionic and metabotropic environment in the brain. Astrocytes also release transmitters that can affect neuronal activity in the vicinity. The results of this study suggest that the theta band habenular neuronal activity is regulated by the activity of astrocytes. Thus, habenular astrocytes were considered to play a role in regulating anxiety.

&amp;nbsp;

&amp;nbsp;

Lead study investigator, Wanqin Tan, says that future treatment of anxiety disorders may be realized by developing a therapeutic strategy that adjusts astrocyte activity in the habenula. &amp;ldquo;Habenular astrocytes tune the &amp;lsquo;marble blues.&amp;rsquo; Based on this, we expect that methods to cope with anxiety could be developed.&amp;rdquo;

&amp;nbsp;



&amp;nbsp;Habenular astrocytes tuning the marble blues. Mice usually do not prefer novel objects and the presence of smooth glass marbles makes them uneasy and anxious. In the marble burying test, the number of marbles buried in the sawdust bedding is counted and administration of anti-anxiety drugs has been shown to reduce the buried number. However, with the floor filled with marbles, the mouse is faced with inescapable anxiety. Theta-band neuronal activity is observed in the habenula when the mouse is in such an anxiogenic environment. With optogenetic alkalinization of habenular astrocytes, the theta-band neuronal activity becomes dissipated. These experiments suggest the role of habenular astrocytes in regulating the tone of anxiety. * The animal in this figure is not a real photograph but a drawn picture and is depicted for the sole purpose of presenting the circumstantial image of the research only.&amp;nbsp;&amp;nbsp;&amp;copy;Wanqin Tan, Ko Matsui

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;



Habenular astrocyte acidification in the anxiogenic environment. (A) Fluorescence sensor protein E2GFP is sensitive to changes in the intracellular pH. The green emission in response to purple light excitation does not change much with changes in the pH; however, the orange emission is largely decreased with pH acidification. E2GFP was selectively expressed in astrocytes and fluorescence fluctuation in the habenula was analyzed using the fiber-photometry method. (B) When the mouse was placed in the anxiogenic all-marble cage, ~ 8 Hz theta-band neuronal activity was detected in the local field potential recorded using a pair of electrodes placed in the habenula. With the optical fiber placed in the habenula, green emission fluorescence showed a downward deflection when the mouse was placed in the all-marble cage. This is the result of an increase in the local brain blood volume. The expansion of the blood vessel diameter likely obstructs the emitted fluorescence from reaching the optical fiber for detection. The orange emission showed a larger downward deflection compared to the green emission. This shows that intracellular pH in the habenular astrocytes was acidified and the local brain blood volume increased when the mice were anxious.&amp;nbsp;&amp;nbsp;&amp;copy;Wanqin Tan, Ko Matsui

&amp;nbsp;

&amp;nbsp;



&amp;nbsp;

Optogenetic alkalinization of habenular astrocytes results in the reduction of anxiety. (A) Archaerhodopsin-T (ArchT) is a light-activated outward proton pump. Photoactivation of ArchT expressed in cell membranes results in intracellular alkalinization. ArchT was selectively expressed in astrocytes and the optical fiber placed in the habenula was used for photoactivation of ArchT. When the mouse was placed in an anxiogenic, all-marble cage environment, theta-band neuronal activity was detected. Photoactivation of the ArchT in the habenular astrocytes led to the reduction of the theta-band. (B) Mice normally prefer a dark room with comfortable bedding. When the mouse was placed in a two-way chamber with a dark room and a bright room with an all-marble floor, the mouse tended to stay in the dark room. However, when the ArchT in the habenular astrocytes were photoactivated, the mouse ventured to the bright room and traveled more in the bright room. These results suggest that when the acidic reaction of the habenular astrocytes is countered by optogenetic alkalinization, anxiety can be reduced.&amp;nbsp;&amp;nbsp;&amp;copy;Wanqin Tan, Ko Matsui

&amp;nbsp;

&amp;nbsp;

Publifation Details:

Title:&amp;nbsp;Anxiety control by astrocytes in the lateral habenula
Authors:&amp;nbsp;Wanqin Tan, Yoko Ikoma, Yusuke Takahashi, Ayumu Konno, Hirokazu Hirai, Hajime Hirase, Ko Matsui
Journal:&amp;nbsp;Neuroscience Research
DOI:&amp;nbsp;https://doi.org/10.1016/j.neures.2024.01.006
Embargo date: February 10, 2024

&amp;nbsp;

Contact:
Ko Matsui,
Super-network Brain Physiology, Graduate School of Life Sciences,
Tohoku University
Email: matsui@med.tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/
</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Team explores role of STING – stimulator of interferon genes – in body’s innate immune system</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2024-01-18T09:59:00+09:00</updated>
	<summary>
When pathogens attack the body, the innate immune system goes to work protecting against the invading disease. The innate immune system is the first line of defense. It detects precisely what the virus or bacteria is and then activates the proteins that fight the pathogens. Wanting to better understand how the body&amp;rsquo;s innate immune system works, a team of scientists undertook a study of STING, a protein that plays a vital role in innate immunity.
The team provides quantitative results, showing how STING, an acronym for stimulator of interferon genes, works in innate immune signaling.&amp;nbsp;
&amp;nbsp;

Their work is published in the journal Nature Communications on Jan 11th, 2024.





A graphical illustration of cholesterol- and palmitoylation-dependent STING clustering at the TGN.
&amp;copy;Institute for Glyco-core Research

&amp;nbsp;


Type I interferons are signaling proteins that respond when they detect the presence of viruses. They play an essential role in the body&amp;rsquo;s immune system, communicating between cells as they fight against pathogens. STING is critical for the type I interferon response to pathogen- or self-derived DNA in the cytosol, the fluid portion of a cell. While STING plays an important role in the body&amp;rsquo;s successful protection against infections, dysregulated STING activity leads to the excessive production of inflammatory mediators that can have a detrimental effect on surrounding cells and tissues. Recent studies have made the connection between STING and a number of autoinflammatory and neurodegenerative diseases.
&amp;nbsp;

&amp;ldquo;STING was discovered as a protein that induces innate immune signals in response to virus-derived non-self DNA. The STING innate immune response has recently been reported to play an important role in cancer immune responses and to contribute to inflammatory pathologies in aging, autoinflammatory, and neurodegenerative diseases, making it a highly attractive target for disease therapy,&amp;rdquo; said Kenichi G.N. Suzuki, a professor at the Institute for Glyco-core Research, Gifu University and a chief at the Division of Advanced Bioimaging, National Cancer Center Research Institute.
&amp;nbsp;&amp;nbsp; &amp;nbsp;&amp;nbsp;&amp;nbsp; &amp;nbsp;&amp;nbsp;&amp;nbsp; &amp;nbsp;&amp;nbsp;&amp;nbsp; &amp;nbsp;&amp;nbsp;&amp;nbsp; &amp;nbsp;&amp;nbsp;&amp;nbsp; &amp;nbsp;&amp;nbsp;&amp;nbsp; &amp;nbsp;
Research suggests that STING may function as a scaffold to activate the TANK-binding kinase 1 (TBK1). TBK1 is a signaling molecule that is activated by receptors when a viral infection occurs. Scaffold proteins do the important job of regulating key signaling pathways. However, up to this point, scientists have lacked direct cellular evidence proving that STING activated the TBK1.&amp;nbsp;
&amp;nbsp;

To analyze the STING cluster, the research team used a live-cell imaging procedure called photoactivated localization microscopy or PALM. They performed this single-molecule imaging of STING with enhanced time resolutions down to 5 milliseconds. They determined that STING becomes clustered at the trans-Golgi network. The trans-Golgi network, or TGN, is a pathway in the body that directs proteins to the correct subcellular destination.
&amp;nbsp;

The team also proved that STING palmitoylation facilitated the STING clustering. Palmitoylation describes a protein modification process in the body. This palmitoylation of STING is required for the cluster formation of STING at the TGN. The Golgi lipid order, along with STING palmitoylation, is essential for the STING signaling. The team examined the role of cholesterol, a lipid that plays an essential role in generating the lipid order in STING&amp;rsquo;s signaling and clustering.
&amp;nbsp;

They used a cholesterol biosensor and an environmentally sensitive probe for lipid membranes, to further demonstrate that cholesterol plays a role in the palmitoylated STING-formed clusters that activate TBK1 at the TGN.
&amp;nbsp;

The team specifically examined the formation of STING clusters as it relates to COPA syndrome. COPA syndrome is a disorder of immune dysregulation characterized by an increase in type I interferon-stimulated genes. This autoimmune disorder can impact multiple systems in the body.
&amp;nbsp;

The team&amp;rsquo;s imaging of TBK1 revealed that the increase in the clustering enhances the association of TBK1. &amp;ldquo;We provide quantitative proof-of-principle for the signaling STING scaffold, reveal the mechanistic role of STING palmitoylation in the STING activation, and resolve the long-standing question of the requirement of STING translocation for triggering the innate immune signaling,&amp;rdquo; said Tomohiko Taguchi, a professor in the Graduate School of Life Sciences, Tohoku University.
&amp;nbsp;

Looking ahead, the team sees potential for this work helping the fight against disease. &amp;ldquo;In the present study, we showed that inhibition of cholesterol transport to TGN markedly suppressed the STING innate immune response. Therefore, based on the results of this study, it is expected that reducing cholesterol levels will be a new tool to treat the diseases associated with STING inflammation,&amp;rdquo; said Suzuki.
&amp;nbsp;

Haruka Kemmoku, Kanoko Takahashi, Kojiro Mukai, Yasunori Uchida, Yoshihiko Kuchitsu, and Tomohiko Taguchi from Tohoku University; Toshiki Mori, Koichiro M. Hirosawa, and Yasunari Yokota from Gifu University; Fumika Kiku and Hiroyuki Arai from the University of Tokyo; Yu Nishioka and Masaaki Sawa from Carna Biosciences, Inc.; Takuma Kishimoto and Kazuma Tanaka from Hokkaido University; and Kenichi G.N. Suzuki from Gifu University and the National Cancer Center, Tokyo.&amp;nbsp;
&amp;nbsp;

This work was funded by JSPS KAKENHI, JSPS Research Fellowship for Young Scientists, AMED-PRIME, JST CREST, Subsidy for Interdisciplinary Study and Research concerning COVID-19 (Mitsubishi Foundation), National Cancer Center Research and Development Fund, Takeda Science Foundation, The Uehara Memorial Foundation, Mizutani Foundation for Glycoscience, Daiichi Sankyo Foundation of Life Science, Research Foundation for Opto-Science and Technology, The Naito Foundation, Grant for Basic Science Research Projects from the Sumitomo Foundation, SGH Cancer Research Grant, Research Grant of the Princess Takamatsu Cancer Research Fund, and the Nagoya University CIBoG program from MEXT WISE program.
&amp;nbsp;

#
&amp;nbsp;

INSERT BOILERPLATE
&amp;nbsp;

Suggested EurekAlert! Summary:
When pathogens attack the body, the innate immune system goes to work protecting against the invading disease. The innate immune system is the first line of defense. It detects precisely what the virus or bacteria is and then activates the proteins that fight the pathogens. Wanting to better understand how the body&amp;rsquo;s innate immune system works, a team of scientists undertook a study of STING, a protein that plays a vital role in innate immunity.



###

About iGCORE:
Institute for Glyco-core Research (iGCORE) is a cutting-edge integrative glycoscience institute that brings together researchers from two universities - Nagoya University and Gifu University under the Tokai National Higher Education and Research System - with outstanding achievements in the fields of glycan synthesis, imaging, glycobiology, and glycomedicine. Through our research, iGCORE is committed to gaining a deeper understanding of the fundamental nature of life, ultimately paving the way for groundbreaking innovations in medicine, such as personalized prevention and early detection of pre-disease.
&amp;nbsp;

About The National Cancer Center Research Institute:
The National Cancer Center Research Institute is one of the largest cancer research institutions in Japan, with over 350 staff, including postgraduate students and research assistants. The Institute covers 20 research areas with 9 independent units, as well as the Fundamental Innovative Oncology Core, established as a common platform serving the entire Center. From highly original basic research to the development of therapeutic and diagnostic drugs, the Institute conducts a wide range of activities in collaboration with other units within the Center.
&amp;nbsp;

Expert Contact：
Kenichi G.N. Suzuki, Ph.D., Professor.
Institute for Glyco-core Research (iGCORE), Gifu University, Gifu, Japan.
Division of Advanced Bioimaging, National Cancer Center Research Institute, Tokyo, Japan.
e-mail: suzuki.kenichi.b7@f.gifu-u.ac.jp
&amp;nbsp;

Tomohiko Taguchi, Ph.D., Professor.
Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan.
e-mail: tomohiko.taguchi.b8@tohoku.ac.jp
&amp;nbsp;

Media Contact：
Yutaka Nibu, Ph.D.
Institute for Glyco-core Research (iGCORE), Tokai National Higher Education and Research System
yutaka.nibu@igcore.nagoya-u.ac.jp
&amp;nbsp;



</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Cutting-edge Biodiversity Models Will Help Assess Nature’s Vital Contributions to People</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2023-12-13T11:00:00+09:00</updated>
	<summary>
People depend on nature in a multitude of ways. Crop pollination, pest management, storm buffering, and carbon capturing are all part of nature&amp;rsquo;s contributions to people (NCP). But these contributions are subject to change&amp;mdash;species that make vital contributions may migrate or even go extinct due to climate change or habitat loss. Forecasting these changes is challenging, but also essential to ensure that humans are adequately prepared to respond.&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

Part of what makes this so challenging is that current NCP estimates typically rely on data incorporating the physical environment and omit information on species. Given that biodiversity is a cornerstone of NCP, many scientists recognize that biodiversity information can help us better assess the current and future state of NCP.&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

In a new opinion paper published in Trends in Ecology and Evolution, lead author Jamie M. Kass, associate professor and head of the Macroecology Lab at Tohoku University&amp;rsquo;s Graduate School of Life Sciences, and an international team of colleagues argue that recent advances in biodiversity modeling and mapping have great potential for improving NCP estimates.

&amp;nbsp;

&amp;nbsp;

&amp;ldquo;Modeling and mapping of biodiversity advance at a rapid pace, making it difficult for researchers outside the field to keep up,&amp;rdquo; points out Kass. &amp;ldquo;Our paper overviewed the current challenges in predicting NCP and explained how two major biodiversity modeling strategies can help: species distribution models and macroecological models.&amp;rdquo;&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

Species distribution models predict species&amp;rsquo; range limits and habitat suitability based on environmental variables like climate and land use. Macroecological models also use environmental variables but instead predict biodiversity patterns such as the richness of species in an area or how much ecological communities change across a region. &amp;nbsp;

&amp;nbsp;

&amp;nbsp;

&amp;ldquo;In the paper we noted that increased adoption of these modeling strategies could allow for a more reliable assessment of the spatial distribution of NCP, for example, by predicting distributions of service-providing species&amp;nbsp;with high biodiversity likely to be important for NCP,&amp;rdquo; adds Kass.

&amp;nbsp;

&amp;nbsp;

To illustrate their point, the authors outlined how multiple advances for these modeling approaches can be employed to predict different dimensions of pollinator diversity, as well as abundance patterns for predators of crop pests and maps of the associated analytical uncertainty.&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

The authors conclude these advances will help us forecast changes in NCP that human societies rely on and also meet international goals for biodiversity conservation.&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

The work for this paper was done in partnership with Keiichi Fukaya (National Institute for Environmental Studies, Japan), Wilfried Thuiller (Universit&amp;eacute; Grenoble Alpes, France), and Akira S. Mori (The University of Tokyo).

&amp;nbsp;



Edible wild foods like oyster mushrooms (left) and pollination provided by bees (right) are two examples of nature&amp;#39;s contributions to people whose distributions can be predicted using biodiversity models. &amp;copy;Keiichi Fukaya

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;



Example workflows that utilize advances in biodiversity modeling to predict nature&amp;rsquo;s contributions to people (NCP) linked to species and ecological communities.&amp;nbsp;&amp;copy;Trend in Ecology &amp;amp; Evolution

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

Publication Details:

Title: Biodiversity modeling advances will improve predictions of nature&amp;rsquo;s contributions to people
Authors: Jamie M. Kass, Keiichi Fukaya, Wilfried Thuiller, Akira S. Mori
Journal: Trends in Ecology and Evolution
DOI: https://doi.org/10.1016/j.tree.2023.10.011

&amp;nbsp;

&amp;nbsp;

Contact

Name: Jamie M. Kass
Affiliation: Tohoku University&amp;nbsp;&amp;nbsp; &amp;nbsp;
Email: kass@tohoku.ac.jp
Website: https://www.lifesci.tohoku.ac.jp/en/research/fields/laboratory.html?id=45417
Twitter: ndimhypervol
&amp;nbsp;

</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Glial Tone of Aggression</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2023-12-05T15:00:00+09:00</updated>
	<summary>
Aggression is often associated as a negative emotion. Uncontrolled aggression can lead to conflict, violence and negative consequences for individuals and society. Yet that does not that mean that aggression serves no purpose. It is an instinctive behavior found in many species that may be necessary for survival. The key is managing and channeling aggression.

&amp;nbsp;

&amp;nbsp;

In a recent study using mice, researchers at Tohoku University have demonstrated that neuron-glial interactions in the cerebellum set the tone of aggression, suggesting that future therapeutic methods could rely on adjusting glial activity there to manage anger and aggression.

&amp;nbsp;

&amp;nbsp;

The findings were detailed in the journal, Neuroscience Research, on November 24, 2023.

&amp;nbsp;

&amp;nbsp;

Scientists have recently recognized the role of the cerebellum in non-motor functions such as social cognition. A malfuctioning cerebellum can occur in autism spectrum disorders and schizophrenia, leading to social interaction difficulties. In particular, it has been reported that a region of the cerebellum, known as the vermis, is associated with aggression in humans. Therefore, the researchers investigated the possibility that Bergmann glial cells in the cerebellar vermis regulate the volume of aggression in mice.

&amp;nbsp;

&amp;nbsp;



Schematic diagram of the mechanism of cerebellar glial cell activity in regulating aggression. 

Gliotransmitter could be released in response to intracellular Ca2+ concentration increase in the cerebellar Bergmann glial cells. Excitatory transmitters such as glutamate would increase the cerebellar Purkinje cell activity. The only output nerve fiber from the cerebellum is the axon of the Purkinje cell (PC). PC activity leads to inhibitory GABA input to the deep cerebellar nuclei (DCN). Excitatory neuronal contacts from the DCN to the ventral tegmental area (VTA) have recently been identified. Dopaminergic neurons in the VTA have been reported to have a significant influence on social behavior, including aggression. Therefore, if the schematic pathway as described works, then an increase in Ca2+ concentration in cerebellar glial cells would be expected to increase PC activity and suppress DCN and VTA activity, leading to reduced aggression. This could lead to an early breakup of fights. On the other hand, a decrease in Ca2+ concentration in cerebellar glial cells would decrease PC activity and increase DCN and VTA activity, which would increase aggression and lead to dominance in fight situations. &amp;copy;Yuki Asano, Ko Matsui

&amp;nbsp;

&amp;ldquo;Cells in the brain can be divided into neurons and glia, and although glia occupy approximately half of the brain, their participation in the brain&amp;rsquo;s information processing, plasticity, and health has long been an enigma,&amp;rdquo; says Professor Ko Matsui of the Super-network Brain Physiology lab at Tohoku University, who led the research. &amp;ldquo;Our newly created fiber photometry method provides a gateway for understanding the physiology of glia.&amp;rdquo;

&amp;nbsp;

&amp;nbsp;

Matsui and his colleagues employed the resident-intruder model, where one mouse (the intruder) goes into the territory of another mouse (the resident). When the unfamiliar male mouse enters the cage, quite commonly, a series of fights break out between the resident male mouse and the intruder. Each combat round lasted about 10 seconds, and these rounds were repeated at a frequency of approximately one per minute. The superiority and inferiority of the resident and intruder dynamically switched within each combat round.&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;



Theta band local field potential (LFP) in the cerebellum upon combat breakup. LFPs were recorded between two electrodes implanted in the mouse cerebellum. In the particular combat round shown, the intruder mouse approached the resident mouse (the recorded mouse), and a fight broke out immediately after contact. Signals recorded during the combat were not analyzed as they contained electrical signals from muscle movements from intense exercise. After the combat breaks up, both mice became stationary. The LFPs in the cerebellum showed oscillations in the frequency range of 4 - 6 Hz (theta band). In separate experiments, when theta band electrical stimulation was delivered via the same cerebellar electrode immediately after the start of the fight, the combat often broke up quickly. It was also shown that ChR2 photostimulation of cerebellar glial cells results in theta band LFP in the cerebellum and also causes the fight to break up early. &amp;copy;Yuki Asano, Ko Matsui

&amp;nbsp;

The fiber photometry method revealed that intracellular Ca2+ levels in cerebellar glia decreased or increased in conjunction with the superiority or inferiority of the fight, respectively. When the combat broke up, the researchers observed 4 to 6 Hz theta band local field potentials in the cerebellum, along with a sustained increase in Ca2+ levels in the glia. Optogenetic stimulation of cerebellar glia induced the emergence of the theta band, casuing an early breakup of the fighting.

&amp;nbsp;

&amp;nbsp;

Glia have been shown to control the local ionic and metabotropic environment in the brain and also to release transmitters that can affect neuronal activity in the vicinity. The results of this study suggest that the theta band cerebellar neuronal activity is regulated by the activity of Bergmann glial cells, thereby demonstrating that cerebellar glial cells play a role in regulating aggression in mice.

&amp;nbsp;

&amp;nbsp;

Lead study investigator, Yuki Asano, says that future anger management strategies and clinical control of excessive aggression and violent behavior may be realized by developing a therapeutic strategy that adjusts glial activity in the cerebellum. &amp;ldquo;Imagine a world without social conflict. By harnessing the innate ability of the cerebellar glia to control aggression, the peaceful future could be become reality.&amp;rdquo;

&amp;nbsp;

&amp;nbsp;




Fiber optic measurement of the local brain environment of the cerebellum. We measured three types of fluorescence (fYFP, dYFP, and fCFP) by inserting an optical fiber into the cerebellum and sending two types of excitation light. By comparing the three fluorescence waveforms, we can estimate the fluctuation of Ca2+ concentration in glial cells, pH fluctuation, and local brain blood volume. Analysis of Ca2+ concentration fluctuations in glial cells during combats revealed that Ca2+ levels decreased significantly when the recorded resident mice fought back and attacked the intruder mice. When the recorded mice were chased from behind by the intruder mice, Ca2+ in the glial cells increased significantly. In addition, the Ca2+ levels remained high even after the fight broke up. These results suggest that cerebellar glial cell activity is linked to mouse aggression. &amp;copy;Yuki Asano, Ko Matsui

&amp;nbsp;

&amp;nbsp;

Publication Details:

Title: Glial tone of aggression
Authors: Yuki Asano, Daichi Sasaki, Yoko Ikoma, Ko Matsui
Journal: Neuroscience Research
DOI:&amp;nbsp;https://doi.org/10.1016/j.neures.2023.11.008

&amp;nbsp;

&amp;nbsp;

Contact:
Ko Matsui,
Super-network Brain Physiology, Graduate School of Life Sciences,
Tohoku University
Email: matsui@med.tohoku.ac.jp
Website: http://www.ims.med.tohoku.ac.jp/matsui/

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;

</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Nutrients drive cellular reprogramming in the intestine</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2023-09-11T13:00:00+09:00</updated>
	<summary>Researchers have unveiled an intriguing phenomenon of cellular reprogramming in mature adult organs, shedding light on a novel mechanism of adaptive growth. The study, which was conducted on fruit flies (Drosophila), provides further insights into dedifferentiation - where specialized cells that have specific functions transform into less specialized, undifferentiated cells like stem cells.

&amp;nbsp;

Until now, dedifferentiation has primarily been associated with severe injuries or stressful conditions, observed during tissue regeneration and diseases like tumorigenesis. However, the researchers have unearthed a previously unknown facet: enteroendocrine cells (EEs) within the intestinal epithelium undergo dedifferentiation into intestinal stem cells (ISCs) in response to nutritional changes, such as recovery from starvation.
&amp;nbsp;

&amp;ldquo;Through meticulous experimentation, we identified a subset of enteroendocrine cells residing in the adult midgut of Drosophila, which exhibit dedifferentiation into ISCs when nutrient levels fluctuate,&amp;rdquo; states Hiroki Nagai, first author of the study and a postdoc who was previously based at Tohoku University&amp;rsquo;s Frontier Research Institute for Interdisciplinary Sciences (FRIS). &amp;ldquo;By utilizing in vivo lineage tracing of EEs and single-cell RNA sequencing, we pinpointed the dedifferentiating EE subpopulation and developed a genetic system for selectively removing ISCs derived from dedifferentiation, a process known as ablation.&amp;rdquo;
&amp;nbsp;

&amp;nbsp;


A brief summary of this study: the Drosophila adult midgut rapidly grows in size upon recovery from starvation (adaptive growth). &amp;copy;Hiroki Nagai et al.

&amp;nbsp;

&amp;nbsp;

Remarkably, the ablation experiments demonstrated that dedifferentiation is vital for ISC expansion and subsequent intestinal growth following food intake. Previous studies using mice relied on massive stem cell ablation to induce dedifferentiation. Yet, in the current research, stem cells were not lost but instead increased in response to nutritional stimuli. This crucial distinction demonstrates that dedifferentiation is not limited to regenerative contexts but significantly contributes to organ remodeling during environmental adaptations.
&amp;nbsp;

Furthermore, the team unraveled the molecular mechanism driving nutrient-dependent dedifferentiation: a deficiency in dietary glucose and amino acids activates the JAK-STAT signaling pathway in EEs, facilitating the conversion of EEs into ISCs during post-starvation recovery. When combined with findings from other studies, this implies that the nutrient-dependent dedifferentiation could be an evolutionary conserved mechanism across species.

&amp;nbsp;

&amp;nbsp;




A detailed summary of this study: the Drosophila adult midgut rapidly grows in size upon the first food intake after eclosion or upon refeeding after starvation. &amp;copy;Hiroki Nagai et al.

&amp;nbsp;

&amp;nbsp;

Yuichiro Nakajima, also formerly based at FRIS and corresponding author of the paper, states that this could lead to being able to control artificial cellular reprogramming in vivo. &amp;ldquo;If we figure out specific nutrients and the detailed signaling that induce dedifferentiation, we could control cell fate plasticity by nutritional intervention and/or pharmacological treatments&amp;rdquo;
&amp;nbsp;

Looking ahead, they hope to focus on examining cell fate plasticity under physiological conditions beyond nutrition, such as reproduction, temperature, light, and exercise. Doing so may uncover novel mechanisms underlying environmental adaptations.
&amp;nbsp;

&amp;nbsp;




Representative image of a dedifferentiating EE which is brightly shining like a star.This is a fluorescent confocal microscope image in which the dedifferentiating EE is shown as a cell with white color (center left). Green indicates expression of stemness marker, magenta marks cells that are originally derived from EEs, and blue indicates expression of EE marker. The white color (green + magenta) means that this cell lost identity as EEs and converted into a stem cell. &amp;copy;Hiroki Nagai et al.



&amp;nbsp;

LINK:

Tohoku University

The Frontier Research Institutes for Interdisciplinary Sciences, Tohoku Univ

&amp;nbsp;

&amp;nbsp;

Publication Details:

Title: Nutrient-driven dedifferentiation of enteroendocrine cells promotes adaptive intestinal growth in Drosophila
Authors: Hiroki Nagai, Luis Augusto Eijy Nagai, Sohei Tasaki, Ryuichiro Nakato, Daiki Umetsu, Erina Kuranaga, Masayuki Miura, and Yu-ichiro Nakajima
Journal: Developmental Cell
DOI: 10.1016/j.devcel.2023.08.022

&amp;nbsp;

&amp;nbsp;

Contact:

Yuichiro Nakajima,
Graduate School of Pharmaceutical Sciences, The University of Tokyo
Email: nakaji97g.ecc.u-tokyo.ac.jp
Website: https://idenut.f.u-tokyo.ac.jp/

&amp;nbsp;



</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>Advanced Technology Reveals Intricate Details of Zinc Transportation in Cells</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2023-09-01T09:00:00+09:00</updated>
	<summary>A group of researchers has unearthed the secrets behind a tiny but crucial protein that shuttles zinc ions (Zn2+) within our bodies. The discovery offers a deeper understanding of how our cells maintain optimal health.

&amp;nbsp;

Zn2+ may be small, but they play a mighty role in our cells. Zinc enables enzyme catalysis, protein folding, DNA binding, and regulating gene expression, with about 10% of the proteins in our body reliant on Zn2+ to function effectively.

&amp;nbsp;

The study, which was published in the journal Nature Communication on August 8, 2023, focused on the Golgi apparatus - a cellular compartment that processes, sorts and distributes cells to their final destination. Within the Golgi, three distinct zinc transporter (ZnT) complexes - ZnT4, ZnT5/6, and ZnT7 - collaborate to usher Zn2+ ions from the cellular interior (cytosol) into the Golgi. While these complexes have long been known to play pivotal roles, the precise mechanisms governing Zn2+ transport within them have remained an enigma.

&amp;nbsp;

&amp;quot;We concentrated our study on the transport protein hZnT7,&amp;quot; says Kenji Inaba, a corresponding author of the study and professor at Tohoku University&amp;#39;s Institute of Multidisciplinary Research for Advanced Materials Sciences. &amp;quot;The study built upon our previous research that hZnT7 plays a vital role in Zn2+ uptake into the cis-Golgi cisterna and regulates the localization, traffic and function of the chaperone protein ERp44.&amp;quot;

&amp;nbsp;




Cryo-EM map of human ZnT7 in complex with Fab at 2.2 a resolution. &amp;copy;Han Ba Bui and Kenji Inaba

&amp;nbsp;

To reveal more about hZnT7, Inaba and his colleagues employed an advanced technique called cryo-electron microscopy (cryo-EM). Two cryo-EM machines, one from Tohoku University and one from the University of Tokyo, could capture detailed images of hZnT7 in action. By using a Fab fragment from a monoclonal antibody that specifically binds hZnT7 the researchers succeeded in determining the cryo-EM structures of hZnT7 at near-atomic resolutions, gaining critical insights into the mechanisms of Zn2+ transport.

&amp;nbsp;

Comparative analysis between hZnT7 and other zinc transporters, including human ZnT8 and bacterial YiiP, exposed distinct structural features of hZnT7. The existence of hZnT7 as a homodimer with varying Zn2+-bound configurations holds particular significance.

Notably, hZnT7 boasts an elongated cytosolic histidine-rich loop (His-loop) that interfaces with the transmembrane metal-binding site, a vital feature governing zinc transfer. During Zn2+ recruitment via the His-loop, hZnT7 undergoes intricate conformational rearrangements, shedding light on an unparalleled mechanism of zinc transport.

&amp;nbsp;

&amp;nbsp;

&amp;nbsp;



Conformational transition of the hZnT7 protomer during the Zn2+ transport from the cytosol to the Golgi lumen. &amp;copy;Han Ba Bui and Kenji Inaba

&amp;nbsp;

It is widely known that hZnT7 is a key player in dietary zinc absorption and controlling body fat. When zinc levels drop in certain parts of the body, it can lead to issues like prostate cancer development in mice and disruptions in how our bodies process insulin.

&amp;nbsp;

Inaba adds their findings will result in greater understandings of the molecular processes with certain pathogens. &amp;quot;With it reported that abnormalities in Golgi-resident ZnT transporters result in fatal diseases such as diabetes, cancers, and immunodeficiency, it&amp;#39;s essential to understand the pathogenic mechanisms of these diseases at the molecular and cellular level.&amp;quot;

&amp;nbsp;



The histidine-rich loop segment is inserted into the cytosolic cavity and coordinated to Zn2+ at the transmembrane metal-binding site for efficient Zn2+ uptake. &amp;copy;Han Ba Bui and Kenji Inaba

&amp;nbsp;

&amp;nbsp;

Publication Details:
Title: Cryo-EM structures of human zinc transporter ZnT7 reveal the mechanism of Zn2+ uptake into the Golgi apparatus
Authors: Han Ba Bui, Satoshi Watanabe, Norimichi Nomura, Kehong Liu, Tomoko Uemura, Michio Inoue, Akihisa Tsutsumi, Hiroyuki Fujita, Kengo Kinoshita, Yukinari Kato, So Iwata, Masahide Kikkawa &amp;amp; Kenji Inaba
Journal: Nature Communications
Date of Publication: August 8th, 2023
DOI: 10.1038/s41467-023-40521-5

&amp;nbsp;

Link

Tohoku University

Institute of Multidisciplinary Research for Advanced Materials, Tohoku University

Graduate School of Science and Faculty of Science Tohoku University

&amp;nbsp;

&amp;nbsp;

Contact:
Kenji Inaba
Institute of Multidisciplinary Research for Advanced Materials
Email: kenji.inaba.a1(at)tohoku.ac.jp
Website: http://www2.tagen.tohoku.ac.jp/lab/inaba/html/

&amp;nbsp;

</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>	<entry>
	<title>How the Tropical Red Swamp Crayfish Successfully Invaded the Cold Regions of Japan</title>
	<link rel="alternate" type="text/html" href="https://www.cn.chiba-u.jp/en/news/press-release_e230802/" />
	<updated>2023-08-24T16:40:00+09:00</updated>
	<summary></summary>
	<id>https://www.cn.chiba-u.jp/en/news/press-release_e230802/</id>
</entry>	<entry>
	<title> Researchers Unearth a New Process By Which Algae Pass on Nurtirients to their Coral Host</title>
	<link rel="alternate" type="text/html" href="https://www.lifesci.tohoku.ac.jp/" />
	<updated>2023-08-23T11:00:00+09:00</updated>
	<summary>Researchers have identified a new pathway by which sugar is released by symbiotic algae. This pathway involves the largely overlooked cell wall, showing that this structure not only protects the cell but plays an important role in symbiosis and carbon circulation in the ocean.

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The findings were reported in the journal eLife on August 18, 2023.

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It is widely known that microalgae enjoy a symbiotic relationship with cnidarians such as corals and sea anemones. The algae use the sun light to produce sugars and other carbohydrates and pass them on to the coral. In return, the coral provides nutrients and shelter to the algae. This fertile coral reefs form in the nutrient-poor tropical oceans and partially addresses the Darwin paradox.

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Yet this symbiotic relationship is both delicate and complex; the slightest change in temperature, pollution or water chemistry can have adverse impacts, leading to coral bleaching or other negative effects on the ecosystem. Scientist still do not understand many of the intricate processes at play when it comes to this relationship, but doing so is crucial for the preservation of coral reefs and the biodiversity they support.

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&amp;ldquo;We discovered that the release of sugar occurs when the algal cell begins degrading its own cell wall,&amp;rdquo; explains Shinichiro Maruyama, lead-author of the research and an associate professor at the University of Tokyo&amp;rsquo;s Graduate School of Frontier Sciences. &amp;ldquo;This breakdown of the cell wall happens even when a symbiotic host is absent and gets enhanced when conditions become more acidic.&amp;rdquo;

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Symbiotic algae live in special compartments within coral cells - symbiosomes - or the guts of marine animals. These environments are generally acidic, and the researchers interpret the sugar release as the algal response to environmental changes in nature.

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The researchers also found the sugar release is mediated by the enzyme cellulase, which is known for its usage in breaking down the cell walls in land plants. When the alga gets treated with a cellulase inhibitor, the amount of sugar released outside of the cell decreases, indicating that the degradation of sugar chains by cellulase is directly related to the increase in sugar release in acidic conditions.

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&amp;ldquo;Our findings suggest that the algal-coral interaction is more complex than ever thought, providing an important piece of the jigsaw puzzle when it comes to carbon cycling in marine environments,&amp;rdquo; adds Maruyama.

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For their next steps, Maruyama and his team will begin clarifying the molecular mechanisms of sugar release, cell wall maintenance, and regulation of enzymatic reactions. Already, they have embarked on a project to disclose the whole diversity of molecules secreted from symbiotic algae, which will further provide insights into what kind of &amp;lsquo;molecular language&amp;rsquo; is exchanged between symbionts and hosts.

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Coral reef ecosystem supported by symbiosis with microalgae

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&amp;nbsp;A model of the pathways of sugar secretion from coral symbiotic algae

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Pocillopora coral in symbiosis with microalgae

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Publication Details

Title:Environmental pH signals the release of monosaccharides from cell wall in coral symbiotic alga
Authors: Yuu Ishii, Hironori Ishii, Takeshi Kuroha, Ryusuke Yokoyama, Ryusaku Deguchi, Kazuhiko Nishitani, Jun Minagawa, Masakado Kawata, Shunichi Takahashi, Shinichiro Maruyama*
Journal: eLife
DOI: https://doi.org/10.7554/eLife.80628

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Link

Tohoku University

Graduate School of Science and Faculty of Science Tohoku University

Graduate School of frontier sciences, the University of Tokyo

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Contact

Name: Shinichiro Maruyama
Affiliation: Laboratory of Integrated Biology
Department of Integrated Biosciences
Graduate School of Frontier Sciences
The University of Tokyo
Email: shinichiro.maruyama@k.u-tokyo.ac.jp
Website: https://www.ib.k.u-tokyo.ac.jp/english/faculty/integrated_biology/
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</summary>
	<id>https://www.lifesci.tohoku.ac.jp/</id>
</entry>

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