UTSA COS Summer Research Experience for 2013
Biochemistry of the Cone Visual Cycle in the Eye
A major emphasis of Dr. Tsin's lab is to investigate the mechanism of pigment regeneration in the cone visual system. Upon light adaptation, cone pigments are bleached to initiate electrical signals in the cone photoreceptors. These signals are then transmitted by neurons to the brain for color visual perception. In order to sustain such visual function, cone pigment must be regenerated in-situ but the underlying mechanism of this cone pigment regeneration is not known. Using animals models, the kinetics of cone pigment bleaching and regeneration are studied in details using biochemical methods. The cellular mechanisms of cone pigment regeneration are also studied using Muller cells and retinal pigment epithelial cells in culture. Specifically, the lab focuses on the abilities of these cells to esterify, isomerize and oxidize the vitamin A (retinoid) chromophore of cone visual pigments.