"Nature vs. Nurture in Drosophila Courtship" Prof. Daisuke Yamamoto

Prof. Daisuke Yamamoto

Professor

Department of Developmental Biology and Neuroscience

Tohoku University Graduate School of Life Sciences

Abstract

The mechanism whereby genes and the environment interact to shape a behavior remains an enigma despite its tremendous importance in understanding human nature. Approximately 25 years ago, I discovered a clue to tackling this problem by isolating a Drosophila mutant that I named satori, males of which preferentially courted males rather than females without copulating (Yamamoto et al., 1991). Later, a genetic complementation test revealed that satori was allelic to fruitless (fru). Molecular cloning of the fru gene (Ito et al., 1996; Ryner et al., 1996) and neuroanatomical demonstration of sexual dimorphisms in fru-expressing neurons (Kimura et al., 2005) led to the notion that the fru gene functions as a master regulator of the development of courtship neural pathways, which operate as hard-wired circuitries to generate genetically determined courtship behavior. Thus genetic mutations in fru result in changes in the courtship target choice in these males. Recent studies (Kohatsu & Yamamoto, 2015; Pan & Baker, 2014) have challenged this view, by showing that inappropriate courtship is suppressed in fru mutants that are raised in isolation.

We have identified the courtship decision-making neuron cluster P1, which is composed of male-specific fru-expressing neurons (Kimura et al., 2008) and thus the effects of environmental factors on neural activities can be explored with single gene/single cell resolutions. Indeed, we have shown that P1 neurons in fru mutants respond differently to courtship-inducing stimuli depending on flies’ social experience (Kohatsu & Yamamoto, 2015). The fru gene products form a complex with chromatin factors (Ito et al., 2012), implicating epigenetic modulation as a possible mechanism of the gene-environment interplay during development and after adult emergence. This study will therefore provide us with a novel framework for the mechanistic understanding of the nature-nurture interactions in behavior.

Biography

Name: Daisuke YAMAMOTO

Doctoral degree field: D. Sc. (Zoology)

Degree date: June 30, 1981

Degree Institution: Hokkaido University

Current Employer: Tohoku University Graduate School of Life Sciences

1976: Bachelor, Tokyo University of Agriculture and Technology (TUAT), Japan. Plant protection

1978: M. Agr. Sci. at the Graduate School of TUAT (Entomology)

1981: D. Sc. (equivalent to Ph.D.) in Zoological Science at Hokkaido University (the thesis title: Electrophysiological studies on the neuromuscular system of insects)

1980-1999: Mitsubishi Kasei Institute of Life Sciences, Researcher (Neurophysiology)

1981-1983: Northwestern University Medical School, USA, Postdoctoral fellow (Pharmacology)

1994-2000: Yamamoto Behavior Genes Project, ERATO (Exploratory Research for Advanced Technology) under JST (Japan Science and Technology Corporation), Project Director

1999-2003: Waseda University, School of Human Sciences, Professor of Genetics.

2003-2005: Waseda University, School of Science and Engineering, Professor of Genetics.

2005-Present: Tohoku University Graduate School of Life Sciences, Professor of Neurogenetics