题目：Synchronization of circadian rhythms in Drosophila

报告人：Prof. Patrick Emery

Patrick Emery, Ph.D is a professor from the University of Massachusetts Medical School. He got his PhD, his Master's degree and his bachelor's degree at University of Geneva, Switzerland. 

时间：2015年09月08日 星期二 13:00-14:00

地点： 北京大学王克桢楼1113会议室

Circadian clocks integrate light and temperature input to remain synchronized with the day/night cycle. In Drosophila, circadian photoreception is based on cell-autonomous detection of light by the photoreceptor CRYPTOCHROME (CRY). CRY targets the key circadian pacemaker protein TIMELESS (TIM) for proteasomal degradation. The molecular mechanisms by which circadian clocks respond to temperature remain however poorly understood. We found that temperature phase-shifts Drosophila circadian clocks through degradation of the pacemaker protein TIMELESS (TIM). This degradation is mechanistically distinct from photic CRY-dependent TIM degradation. Thermal TIM degradation is triggered by cytosolic calcium increase and CALMODULIN binding to TIM, and is mediated by the atypical calpain protease Small Optic Lobes (SOL). This thermal input pathway and CRY-dependent light input thus converge on TIM, providing a molecular mechanism for the natural integration of circadian light and temperature inputs.