Visual pigments are the light-absorbing molecules that mediate vision. They consist of an apoprotein, opsin, covalently linked to cis-retinal (By similarity). Required for the maintenance of cone outer segment organization in the ventral retina, but not essential for the maintenance of functioning cone photoreceptors (PubMed:21219924, PubMed:25416279). Involved in ensuring correct abundance and localization of retinal membrane proteins (PubMed:25416279). May increase spectral sensitivity in dim light (PubMed:11055434). Expressed in the inner and outer segments of cone photoreceptor cells in the retina (at protein level). Phosphorylated on some or all of the serine and threonine residues present in the C-terminal region. Knockout mice are viable with normal gross morphology (PubMed:21219924). Cone photoreceptors are normal and provide a normal flash response, however cone cells in the ventral retina have thin or undetectable outer segments that exhibit mild to severe disordered organization (PubMed:21219924, PubMed:25416279). Cone cells show increased sensitivity to mid-wavelength light, potentially as result of increased protein Opn1mw abundance (PubMed:21219924). Lrat and Opn1sw double knockout mice show no change in cone cell viability in the central and ventral retina, however show shorter and swollen outer and inner segments at twelve months of age (PubMed:25416279). Double knockout of Lrat and Opn1sw results in a reduction in the slow degeneration of dorsal cone photoreceptors compared to Lrat knockout mice (PubMed:25416279). Lrat and Opn1sw double knockout mice show a reduced abundance of transmembrane and peripheral membrane-associated proteins in cone inner and outer segments (PubMed:25416279). Belongs to the G-protein coupled receptor 1 family. Opsin subfamily.