光照对中枢和外周组织生物钟Clock基因表达的影响

【目的】分析光照对中枢和外周组织生物钟Clock基因mRNA表达的影响。【方法】采用竞争性RT-PCR法测定不同光照条件下中枢和外周组织中Clock基因的昼夜表达规律。【结果】发现Clock基因mRNA不仅在中枢(下丘脑视交叉上核，SCN)，而且在外周(淋巴细胞)均具有昼夜节律性表达。在光照-黑暗交替光制下，中枢和外周Clock基因的表达几乎呈反相关系；在全黑暗条件下，Clock基因mRNA的表达存在昼夜节律，中枢和外周的Clock基因mRMA表达的峰值相位存在约8h的相位差。【结论】Clock基因的昼夜节律表达具内源性特征；光照影响Clock基因mRNA的表达。

Effects of Light on Circadian Expression of Clock Gene in Central and Peripheral Tissues

Objective To analyze the effects of light on circadian expression of Clock mRNA in central and peripheral tissues.[Methods] mRNA of Clock gene under different regimes in different tissues was measured by competitive RT_PCR.[Results]Levels of the Clock mRNA in suprachiasmatic nuclei(SCN)and lymphocytes changed in a circadian pattern under different light regimes.Circadian expression of the Clock gene showed a reverse phase between the central and peripheral tissues under light_dark regime,with a phase difference of about8h under constant dark regime.[Conclusion]Circadian expression of the Clock gene is endogenetic and can be effected by light.