Temporal and spatial changes in the cellular and subcellular concentrations of photoreceptor cell gene products appear to be important features of phototransduction in rod photoreceptor cells. The time course of the rapid, light-dependent movement of S-antigen (S-Ag) (48k; Arrestin) from the inner segments to the outer segments was analyzed using polyclonal and monoclonal antibodies. The concentrations of mRNA change about threefold for rhodopsin and about sixfold for S-Ag in cyclic, independent modes during the normal light-dark cycle. Kinetic analysis indicates that the oscillations of S-Ag mRNA levels are due to changes in the transcriptional activity of the gene itself. An experimental model is presented summarizing the relationships between mRNA levels, protein localization, disc shedding, and phototransduction in the photoreceptors cells.