Identification of novel photoreceptors in the nematode Pristionchus pacificus

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K15903
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 46010:Neuroscience-general-related
• Research Institution: Hiroshima University
• Principal Investigator: Okumura Misako 広島大学, 統合生命科学研究科(理), 准教授 (40806486)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: 線虫 / Pristionchus pacificus / 光忌避行動 / 光受容体 / 順遺伝学的スクリーニング / ゲノム編集

Outline of Final Research Achievements

The nematode Pristionchus pacificus has no eyes and no known photoreceptors in its genome, but it can respond to light and exhibits light avoidance behavior. In this study, we aimed to clarify how the nematode P. pacificus senses light. We have established an assay system for light avoidance behavior and found that P. pacificus exhibits avoidance behavior in response to short-wavelength light. We conducted a forward genetic screening and isolated six mutant lines that did not show light-avoidance behavior, and identified the causal genes in five mutant lines. In addition, we identified candidate light-sensing cells and will confirm whether these cells are involved in light sensing, aiming to elucidate the molecular and neural mechanisms of light sensing.

Free Research Field

神経科学

Academic Significance and Societal Importance of the Research Achievements

本研究によって新規光受容体を同定することは，動物の光感知の考え方を大きく転換させる可能性を秘める．本研究で同定する光受容体は線虫以外の動物にも保存されている可能性があり，光による新たな生理機能制御の解明につながると考えている．一方，本研究で同定する光受容体は線虫でのみ保存されている可能性もあるが，新しい特性をもつ光受容体の同定は，チャネルロドプシンのような新しい光遺伝学的手法の開発にもつながる．本研究によりP. pacificusを用いて光感知の分子基盤を明らかにすることは，線虫における光感知機構の解明だけでなく，動物における新たな光受容体の発見や，光受容体の進化の解明に重要な知見を与えうる．