Distribution and the circadian regulation of Gq/11[alpha] porteins in the vertebrate retina

grantor: University of TorontoRecent studies have demonstrated that the retina of mammals contain an intrinsic circadian clock. The molecular components of this machinery have not been entirely identified. The expression of some signal transduction proteins have been shown to oscillate over a 24 hour light-dark cycle and as such they may play an important role in circadian regulatory processes. I have used this system to explore the cellular distribution and circadian regulation of Gq/11$\alpha$ in rat retina. Gq/11$\alpha$ was found to be expressed in the inner and outer plexiform layers of the retina. Quantitation of Gq/11$\alpha$ and Gt$\alpha$ concentrations during light-dark cycles indicate that their concentrations change in a cyclic manner. The regulation of Gq/11$\alpha$ and Gt$\alpha$ were determined to be circadian in nature by quantitating G protein concentrations under constant dark and light conditions. My results also suggest that Gt$\alpha$ and Gq/11$\alpha$ concentrations may be regulated through different mechanisms. These findings may help us understand circadian regulatory mechanisms within the retina and their role in maintaining the health of the retina.M.Sc