Photoreceptor required for image-forming vision at low light intensity. Required for photoreceptor cell viability after birth (By similarity). Light-induced isomerization of 11-cis to all-trans retinal triggers a conformational change that activates signaling via G-proteins (PubMed:10926528, PubMed:12044163, PubMed:11972040, PubMed:16908857, PubMed:16586416, PubMed:17060607, PubMed:17449675, PubMed:18818650, PubMed:21389983, PubMed:22198838, PubMed:23579341, PubMed:25205354, PubMed:27458239). Subsequent receptor phosphorylation mediates displacement of the bound G-protein alpha subunit by the arrestin SAG and terminates signaling (PubMed:1396673, PubMed:15111114). Homodimer (PubMed:23303210, PubMed:18563085). May form a complex composed of RHO, GRK1 and RCVRN in a Ca(2+)-dependent manner; RCVRN prevents the interaction between GRK1 and RHO (PubMed:17020884). Interacts with GRK1 (By similarity). Interacts (phosphorylated form) with SAG (PubMed:26200343, PubMed:15111114, PubMed:15351781, PubMed:23579341, PubMed:25205354). Interacts with GNAT1 (PubMed:23303210, PubMed:28655769, PubMed:18818650, PubMed:21389983, PubMed:23579341, PubMed:26526852). Interacts with GNAT3 (PubMed:22198838, PubMed:27458239). SAG and G-proteins compete for a common binding site (By similarity). Interacts with PRCD; the interaction promotes PRCD stability (PubMed:27509380). Synthesized in the inner segment (IS) of rod photoreceptor cells before vectorial transport to disk membranes in the rod outer segment (OS) photosensory cilia. Expressed in rod-shaped photoreceptor cells in the retina that mediate vision in dim light (at protein level). Phosphorylated on some or all of the serine and threonine residues present in the C-terminal region. Contains one covalently linked retinal chromophore. Upon light absorption, the covalently bound 11-cis-retinal is converted to all-trans-retinal. After hydrolysis of the Schiff base and release of the covalently bound all-trans-retinal, active rhodopsin is regenerated by binding of a fresh molecule of 11-cis-retinal. Belongs to the G-protein coupled receptor 1 family. Opsin subfamily.