Kaushik Rachna, Nawathean Pipat, Busza Ania, Murad Alejandro, Emery Patrick, Rosbash Michael
Howard Hughes Medical Institute, Brandeis University, Waltham, Massachusetts, United States of America.
PLoS Biol. 2007 Jun;5(6):e146. doi: 10.1371/journal.pbio.0050146.
Drosophila cryptochrome (CRY) is a key circadian photoreceptor that interacts with the period and timeless proteins (PER and TIM) in a light-dependent manner. We show here that a heat pulse also mediates this interaction, and heat-induced phase shifts are severely reduced in the cryptochrome loss-of-function mutant cry(b). The period mutant per(L) manifests a comparable CRY dependence and dramatically enhanced temperature sensitivity of biochemical interactions and behavioral phase shifting. Remarkably, CRY is also critical for most of the abnormal temperature compensation of per(L) flies, because a per(L); cry(b) strain manifests nearly normal temperature compensation. Finally, light and temperature act together to affect rhythms in wild-type flies. The results indicate a role for CRY in circadian temperature as well as light regulation and suggest that these two features of the external 24-h cycle normally act together to dictate circadian phase.
果蝇隐花色素（CRY）是一种关键的昼夜节律光感受器，它以光依赖的方式与周期蛋白和无时间蛋白（PER和TIM）相互作用。我们在此表明，热脉冲也介导这种相互作用，并且在隐花色素功能缺失突变体cry(b)中，热诱导的相位偏移会严重减少。周期突变体per(L)表现出类似的CRY依赖性，并且生化相互作用和行为相位偏移的温度敏感性显著增强。值得注意的是，CRY对于per(L)果蝇的大多数异常温度补偿也至关重要，因为per(L); cry(b)品系表现出几乎正常的温度补偿。最后，光和温度共同作用影响野生型果蝇的节律。结果表明CRY在昼夜节律温度以及光调节中发挥作用，并表明外部24小时周期的这两个特征通常共同作用来决定昼夜节律相位。
