Regulation of Retinal Functions by Light and a Circadian Clock

University Of Florida, Gainesville FL

Investigators

Abstract

The retinas of animals, including man, that live in diurnal environments undergo daily changes in structure and function. These changes, which are critical for normal vision, are driven by the separate and combined effects of light and signals from internal, 24 hour (circadian) clocks. This research will help elucidate the unknown biochemical mechanisms responsible for these changes. The visual system of the horseshoe crab Limulus polyphemus is studied because the organization of the Limulus visual system is relatively simple, and the daily changes that occur in its eyes and photoreceptors are robust, diverse, well characterized, and easily controlled. The studies focus on a unique protein in Limulus photoreceptors, an unconventional class III myosin that is modified by both circadian signals and light. The tools of molecular biology, biochemistry and cell biology will be applied to test myosinIII's role in clock-driven structural and functional changes in photoreceptors. The results will contribute to an understanding of vision by furthering knowledge of biochemical processes underlying daily changes in photoreceptor structure and function, of cell biology by clarifying the function of an unusual structural component of photoreceptors, and of myosin biochemistry by furthering understanding of a wide-spread class of unconventional myosins about which little is known. This research will also contribute directly to the development of the next generation of scientists by providing training to postdoctoral fellows, undergraduates, and minority high school students. Furthermore, research findings are regularly shared through public lectures, discussions and articles with lay adult members of the community, many of whom are docents in the Whitney Lab's K-12 outreach programs that impact over 2000 local students each year. Therefore, in addition to generating new knowledge, this research will promote science literacy in the local community and an interest in science among young local students.