Rivkees S A, Weaver D R, Reppert S M
Laboratory of Developmental Chronobiology, Children's Service, Massachusetts General Hospital, Boston 02114.
Brain Res. 1992 Dec 11;598(1-2):332-6. doi: 10.1016/0006-8993(92)90203-l.
Oct-2 is a transcriptional activating factor that is expressed in the suprachiasmatic nuclei (SCN), the site of a biological clock. We examined in rats whether Oct-2 gene expression is regulated by the circadian pacemaker or by light using quantitative in situ hybridization. The ontogeny of Oct-2 gene expression in the SCN was also studied. Oct-2 mRNA levels remained constant throughout the circadian cycle. In contrast to c-fos mRNA levels which are acutely induced by acute light exposure at night, Oct-2 mRNA levels were not increased by light exposure at night. At gestational day 18, the first age the SCN are anatomically distinct, a prominent Oct-2 hybridization signal was present in the SCN. Our results suggest that Oct-2 is constitutively expressed in the SCN and is present from the time the SCN are discernible as discrete nuclei in fetal brain.
Oct-2是一种转录激活因子，在生物钟的位点视交叉上核（SCN）中表达。我们利用定量原位杂交技术在大鼠中研究了Oct-2基因表达是受昼夜节律起搏器调节还是受光照调节。同时也研究了SCN中Oct-2基因表达的个体发生情况。在整个昼夜周期中，Oct-2 mRNA水平保持恒定。与在夜间急性光照可急性诱导的c-fos mRNA水平相反，夜间光照不会使Oct-2 mRNA水平升高。在妊娠第18天，即SCN在解剖学上首次明显可见的年龄，SCN中存在明显的Oct-2杂交信号。我们的结果表明，Oct-2在SCN中持续表达，并且从SCN在胎儿脑中可辨认为离散核的时候就已存在。
