In PR cells, PrBP/δ traffics prenylated cargo such as PDE6, Rab28, and rhodopsin kinase (GRK1) from the site of protein synthesis (inner segment) to the retinal outer segment, and its homozygous deletion causes slow, progressive rod-cone dystrophy (101, 102). The gene discussed is GRK1; the disease is cone-rod dystrophy.