論文

査読有り
2017年5月23日

Adaptation of cone pigments found in green rods for scotopic vision through a single amino acid mutation

Proceedings of the National Academy of Sciences of the United States of America
  • Keiichi Kojima
  • ,
  • Yuki Matsutani
  • ,
  • Takahiro Yamashita
  • ,
  • Masataka Yanagawa
  • ,
  • Yasushi Imamoto
  • ,
  • Yumiko Yamano
  • ,
  • Akimori Wada
  • ,
  • Osamu Hisatomi
  • ,
  • Kanto Nishikawa
  • ,
  • Keisuke Sakurai
  • ,
  • Yoshinori Shichida

114
21
開始ページ
5437
終了ページ
5442
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1073/pnas.1620010114
出版者・発行元
National Academy of Sciences

Most vertebrate retinas contain a single type of rod for scotopic vision and multiple types of cones for photopic and color vision. The retinas of certain amphibian species uniquely contain two types of rods: red rods, which express rhodopsin, and green rods which express a blue-sensitive cone pigment (M1/SWS2 group). Spontaneous activation of rhodopsin induced by thermal isomerization of the retinal chromophore has been suggested to contribute to the rod's background noise, which limits the visual threshold for scotopic vision. Therefore, rhodopsin must exhibit low thermal isomerization rate compared with cone visual pigments to adapt to scotopic condition. In this study, we determined whether amphibian blue-sensitive cone pigments in green rods exhibit low thermal isomerization rates to act as rhodopsin-like pigments for scotopic vision. Anura blue-sensitive cone pigments exhibit low thermal isomerization rates similar to rhodopsin whereas Urodela pigments exhibit high rates like other vertebrate cone pigments present in cones. Furthermore, by mutational analysis we identified a key amino acid residue, Thr47, that is responsible for the low thermal isomerization rates of Anura blue-sensitive cone pigments. These results strongly suggest that, through this mutation, anurans acquired special blue-sensitive cone pigments in their green rods, which could form the molecular basis for scotopic color vision with normal red rods containing green-sensitive rhodopsin.

リンク情報
DOI
https://doi.org/10.1073/pnas.1620010114
PubMed
https://www.ncbi.nlm.nih.gov/pubmed/28484015
Scopus
https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85019571218&origin=inward 本文へのリンクあり
Scopus Citedby
https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85019571218&origin=inward
ID情報
  • DOI : 10.1073/pnas.1620010114
  • ISSN : 1091-6490
  • ISSN : 0027-8424
  • eISSN : 1091-6490
  • PubMed ID : 28484015
  • SCOPUS ID : 85019571218

エクスポート
BibTeX RIS