Regulation of Retinal Functions by Light and a Circadian Clock

脊椎动物和无脊椎动物的视网膜功能都受光和生物钟的调节。在鲎（Limulus polyphemus）中，光和生物钟对视网膜结构和功能的相互作用得到了很好的表征。这些研究的目的是阐明大部分未知的生化底物和机制，以及光和生物钟对视网膜的影响和相互作用。已经确定了两种有趣的底物。其中一个是pp46A，它可能参与了生物钟调节的光驱动通路。另一个pp122，在一个时钟驱动的途径中，可能被光调制。pp46A抑制由光引发的级联转导，pp122对夜间发生的光感受器结构的时钟驱动变化至关重要的假设将被研究。分子、生化和免疫化学方法将被应用于表征这些蛋白质及其功能。光和生物钟在调节视网膜功能关键蛋白——视蛋白pp46A和pp122中的相互作用将被确定。这些研究将提供关于视网膜昼夜变化的生化过程的新知识，这些变化是正常视力所必需的。

Retinal functions in both vertebrates and invertebrates are regulated by light and a circadian clock. In the horseshoe crab, Limulus polyphemus, the interactions of light and a circadian clock on retinal structure and function are particularly well characterized. The goal of these studies is to clarify the largely unknown biochemical substrates and mechanisms underlying the effects of, and the interactions between, light and the circadian clock on the retina. Two interesting substrates have been identified. One, pp46A, probably participates in a light-driven pathway modulated by the circadian clock. The other pp122, is in a clock-driven pathway that is probably modulated by light. The hypothesis that pp46A quenches the transduction cascade initiated by light and that pp122 is critical for clock-driven changes in the structure of the photoreceptor that occur at night will be investigated. Molecular, biochemical and immunochemical approaches will be applied to characterize these proteins and their functions. The interactions between light and a circadian clock in regulation of proteins critical for retinal function, opsin, pp46A and pp122, will be determined. These studies will provide new knowledge of the biochemical processes that underlie the day to night changes in the retina that are required for normal vision.