Plays a role in rod outer segment (ROS) morphogenesis (By similarity). May play a role with PRPH2 in the maintenance of the structure of ROS curved disks (By similarity). Plays a role in the organization of the ROS and maintenance of ROS disk diameter (By similarity). Involved in the maintenance of the retina outer nuclear layer (By similarity). {ECO:0000250|UniProtKB:P32958, ECO:0000250|UniProtKB:P52205}. This is the function of ENSG00000149489 (ROM1, retinal outer segment membrane protein 1).