Structural insights into spectral tuning and retinal exchange in cone visual pigments

• 成果类型: Article
• 署名作者: Ohashi, Sayaka; Katayama, Kota; Kojima, Asato; Yang, Xuchun; Fukuda, Masahiro; Sacchetta, Filippo; Suno, Ryoji; Sugita, Yukihiko; Nuemket, Nipawan; Kim, Suhyang; Kobayashi, Kazuhiro; Imai, Hiroo; Iwata, So; Nango, Eriko; Kobayashi, Takuya; Noda, Takeshi; Olivucci, Massimo; Kato, Hideaki E.; Kandori, Hideki
• 署名单位: Nagoya Institute of Technology; Japan Science & Technology Agency (JST); Japan Science & Technology Agency (JST); University of Tokyo; University of Siena; Japan Science & Technology Agency (JST); Kansai Medical University; Kyoto University; Japan Synchrotron Radiation Research Institute; RIKEN; Kyoto University; Kyoto University; Tohoku University; University System of Ohio; Bowling Green State University; University System of Ohio; Bowling Green State University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-8075; 1095-9203
• DOI: 10.1126/science.adz3996
• 发表日期: 2026-06-25
• 页码: eadz3996
• 关键词: COLOR-VISION; crystal-structure; molecular-basis; MONKEY GREEN; protein; red; rhodopsin; EVOLUTION; rod; activation

摘要

Color vision in catarrhine primates relies on red-, green-, and blue-sensitive cone pigments that share an 11-cis-retinal chromophore but differ in absorption maxima. Red and green pigments arose by recent gene duplication and differ at only a few residues. Here, we report cryo-electron microscopy structures of red and green cone pigments from the cynomolgus macaque (Macaca fascicularis) integrated with low-temperature vibrational spectroscopy and quantum mechanical and molecular mechanical modeling. The red-green spectral shift is dominated by threonine 285, the hydroxyl dipole of which modulates chromophore electrostatics, whereas steric effects appear modest. We also identified membrane-facing lateral openings in cone pigments but not in inactive rhodopsin. Comparisons with active-state structures suggest activation-dependent gating, and mutational and spectroscopic analyses support a role for this opening in retinal uptake and rapid pigment regeneration.