Molecular and Chemical Life Science :
Multilevel Biomolecular Structure and Dynamics


Associate Professor OKUMURA Masaki (C)
Campus Katahira campus
Laboratory Molecular Analysis of Biological Functions
Tel +81-22-795-5764
E-mail okmasaki@tohoku.ac.jp
Website https://web.tohoku.ac.jp/okumura/#
2006     B.S. Kwansei Gakuin University School of Science
2010    Research Fellowship for Young Scientists, JSPS DC2 (Kwansei Gakuin University)
2011     Ph.D. Kwansei Gakuin University School of Science and Technology
2011    Research Fellowship for Young Scientists, JSPS PD (Kwansei Gakuin University)
2012    Post-doctor (Kyushu University)
2013     Research Fellowship for Young Scientists, JSPS PD (Tohoku University)
2016    Assistant Professor (Institute of Multidisciplinary Research for Advanced Materials, Tohoku University)
2017     Assistant Professor (Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Japan, Tohoku University)
2022     Associate Professor (Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Japan, Tohoku University)
Selected Publications
  1. Okumura, M.*, Kanemura, S., Matsusaki, M., Kinoshita, M., Saio, T., Ito, D., Hirayama, C., Kumeta, H., Watabe, M., Amagai, Y., Lee, Y.H., Akiyama, S., and Inaba, K.* “A unique leucine-valine adhesive motif supports structure and function of protein disulfide isomerase P5 via dimerization” Structure 29 1-14 (2021)
  2. Okumura, M., Noi, K., and Inaba, K.* “Visualization of structural dynamics of protein disulfide isomerase enzymes in catalysis of oxidative folding and reductive unfolding” Current Opinion in Structural Biology 66 49-57 (2021)
  3. Matsusaki, M., Okada, R., Tanikawa, Y., Kanemura, S., Ito, D., Lin, Y., Watabe, M., Yamaguchi, H., Saio, T., Lee, YH., Inaba, K., and Okumura, M.* “Functional Interplay Between P5 And PDI/ERp72 To Drive Protein Folding” Biology 10(11) 1112 (2021)
  4. Matsusaki, M., Kanemura, S., Kinoshita, M., Lee, Y.H., Inaba, K.,* and Okumura, M.* “The Protein Disulfide Isomerase family: from Proteostasis to Pathogenesis” Biochim Biophys Acta-general subjects 1864 129338 (2020)
  5. Okumura, M.*, Noi, K., Kanemura, S., Kinoshita, M., Saio, T., Inoue, Y., Hikima, T., Akiyama, S., Ogura, T.* and Inaba, K.* “Dynamic assembly of protein disulfide isomerase in catalysis of oxidative folding” Nature Chemical Biology 15, 499-509 (2019)
  6. Okada, S., Matsusaki, M., Arai, K., Hidaka, Y., Inaba, K., Okumura, M.*, and Muraoka, T.* “Coupling effects of thiol and urea-type groups for promotion of oxidative protein folding” Chem Commun (Camb) 55 759-762 (2019)
Activities in Academic Societies
Protein Science Society of Japan, the Molecular Biology Society of Japan
Biology A, Biology B

Recent Activities

Protein folding coupled with disulfide bond formation, that is oxidative protein folding, proceeds mainly in the endoplasmic reticulum (ER). Greater than 20 Protein Disulfide Isomerase family members (PDIs) are conserved in the mammalian ER to catalyze this reaction. However, it remains an important open question how PDIs recognize various substrates and guide their proper folding through disulfide bond formation and isomerization. The goal of this study is to understand how protein homeostasis is maintained in the mammalian ER. To this end, I employ multiple approaches including single-molecule observation by high-speed AFM, NMR/SAXS analyses in solution, X-ray crystal structure analysis, and several biochemical assays. Diabetes and neurodegenerative diseases are caused by impairment of the protein quality control systems in cells, and hence this study will provide molecular insights into the mechanism underlying these diseases.