As a child, I was an amateur entomologist, running over hills and fields to collect insects. I was drawn not only to the wide structural variety of these small creatures, but also to their myriad habits. I was curious as to why individuals belonging to the same species but neighboring habitats often appear so different. Maybe a small change in some gene produced a subtle change in behavior, ultimately leading to speciation? In seeking the answers to such questions, I continued to pursue insect biology, and finally made it my profession.
The Molecular Biology Society of Japan, The Japan Neuroscience Society, The Genetics Society of Japan
Life Science B (for 1st grade students, School
Our major efforts have been dedicated to the study of fru, which is now regarded as a “master control gene” for male courtship circuitry formation. The fru gene encodes a series of putative transcription factors Fru, which recruit chromatin regulators to ~100 sites on the chromosome to induce global changes in gene transcription. We hypothesize that the “femaleness” or “maleness” of neurons is an outcome of chromatin state changes that Fru induce. To verify this hypothesis, we are attempting to determine the consensus Fru-binding sequence, which we hope will allow us to identify almost all Fru target genes in the genome. At the other end of our wide research spectrum, we are attempting to produce fru mutants in non-model species of Drosophila by means of the CRISPR/Cas9 system, with the aim of gaining insight into the genomic basis for evolutionary changes in species-specific courtship behavior.
Figure 1: A spinster mutant female rejecting a wild-type courter male
Current research activities in this laboratory began with curiosity regarding the amazing diversity of organisms and how it was achieved. One might think these are questions of ecology. However, I have been motivated to employ molecular biology and genetics to address these questions. I believe that one of the keys to understanding evolution is clarification of the molecular-level genetic (and genomic) changes that direct the various phenotypic changes. In any case, our drive to reveal hidden layers of causality should lead to new insights into hitherto unknown biological mechanisms.
Figure 2: D. Yamamoto (left) and Ken Kaneshiro (right) collecting Hawaiian endemic Drosophila on the island of Maui.