光谱调谐和视锥色素视网膜交换的结构见解，这一成果由日本名古屋工业大学
本文报道了猕猴（Macaca fascicularis）红色和绿色锥体色素的低温电子显微镜结构，并结合低温振动光谱和量子力学和分子力学建模。红绿光谱位移主要由苏氨酸285控制，苏氨酸285的羟基偶极子调节发色团的静电，而立体效应则不大。研究人员还在视锥色素中发现了面向膜的外侧开口，但在无活性视紫红质中没有。与活性状态结构的比较表明激活依赖性门控，突变和光谱分析支持该开口在视网膜摄取和快速色素再生中的作用。
研究人员表示，卡氏灵长类动物的色觉依赖于对红、绿、蓝敏感的视锥色素，它们共享一个11-顺式视网膜发色团，但最大吸收量不同。红色和绿色色素是由最近的基因复制产生的，只在几个残基上有所不同。
附：英文原文
Title: Structural insights into spectral tuning and retinal exchange in cone visual pigments
Author: Sayaka Ohashi, Kota Katayama, Asato Kojima, Xuchun Yang, Masahiro Fukuda, Filippo Sacchetta, Ryoji Suno, Yukihiko Sugita, Nipawan Nuemket, Suhyang Kim, Kazuhiro Kobayashi, Hiroo Imai, So Iwata, Eriko Nango, Takuya Kobayashi, Takeshi Noda, Massimo Olivucci, Hideaki E. Kato, Hideki Kandori
Issue&Volume: 2026-06-25
Abstract: 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.
DOI: adz3996
Source: https://www.science.org/doi/10.1126/science.adz3996