Thresher R J, Vitaterna M H, Miyamoto Y, Kazantsev A, Hsu D S, Petit C, Selby C P, Dawut L, Smithies O, Takahashi J S, Sancar A
Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA.
Science. 1998 Nov 20;282(5393):1490-4. doi: 10.1126/science.282.5393.1490.
Cryptochromes are photoactive pigments in the eye that have been proposed to function as circadian photopigments. Mice lacking the cryptochrome 2 blue-light photoreceptor gene (mCry2) were tested for circadian clock-related functions. The mutant mice had a lower sensitivity to acute light induction of mPer1 in the suprachiasmatic nucleus (SCN) but exhibited normal circadian oscillations of mPer1 and mCry1 messenger RNA in the SCN. Behaviorally, the mutants had an intrinsic circadian period about 1 hour longer than normal and exhibited high-amplitude phase shifts in response to light pulses administered at circadian time 17. These data are consistent with the hypothesis that CRY2 protein modulates circadian responses in mice and suggest that cryptochromes have a role in circadian photoreception in mammals.
隐花色素是眼睛中的光活性色素，有人提出它们可作为昼夜节律光色素发挥作用。对缺乏隐花色素2蓝光光感受器基因（mCry2）的小鼠进行了昼夜节律相关功能测试。突变小鼠对上丘核（SCN）中mPer1的急性光诱导敏感性较低，但SCN中mPer1和mCry1信使核糖核酸呈现正常的昼夜节律振荡。在行为方面，突变体的内在昼夜节律周期比正常情况长约1小时，并且在昼夜节律时间17给予光脉冲时表现出高振幅相移。这些数据与CRY2蛋白调节小鼠昼夜节律反应的假设一致，并表明隐花色素在哺乳动物的昼夜节律光感受中起作用。
