2026/06/25 by Sayaka Ohashi, Kota Katayama, Asato Kojima +16 · 1 voice
Biochemistry, Genetics and Molecular Biology · Neuroscience · #Neuroscience and Neuropharmacology Research #Photoreceptor and optogenetics research #Retinal Development and Disorders
paper · doi:10.1126/science.adz3996
openalex publication_date 2026/06/25 · openalex created_date 2026/06/26 · openalex updated_date 2026/07/23
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.