Analysis of uncharacterized phototransduction system in the vertebrate photoreceptor cells

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K07437
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Animal physiology/Animal behavior
• Research Institution: Kyoto University
• Principal Investigator: Yamashita Takahiro 京都大学, 理学研究科, 助教 (50378535)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 光受容蛋白質 / 視細胞

Outline of Final Research Achievements

Opn5 forms one of the photoreceptive protein, opsin, groups, whose genes are widely distributed in vertebrate genomes. We previously revealed that vertebrate Opn5 is classified into several subgroups and is diversified based on their molecular properties and tissue distribution patterns. In this study, we analyzed one of the subgroups, Opn5n, which is sensitive to visible light and is expressed in the photoreceptor cells. We constructed knock-out medaka fish line and revealed that the fish shows deficient morphological changes in dark-adapted and light-adapted retinas. In addition, we characterized the key amino acid residue(s) responsible for the visible light sensitivity in Opn5n.

Free Research Field

分子生理学

Academic Significance and Societal Importance of the Research Achievements

動物は外界の光環境の変化から多様な情報を手に入れている。そのために重要な光センサーがオプシン類である。動物のゲノムでオプシン遺伝子を探索すると、哺乳類は10以下と少ないが、他の脊椎動物ではその倍以上持つものが多い。つまり、哺乳類以外の脊椎動物はより多様なオプシンを用いて、光環境の変化から多彩な情報を手に入れていると考えられる。本研究では、そのようなことに関わる１つのオプシン遺伝子を解析し、哺乳類では見られない光応答システムを明らかにできた。