Melatonin induces Cry1 expression in the pars tuberalis of the rat
Melatonin induces Cry1 expression in the pars tuberalis of the rat
复制标题
DOI：
10.1016/s0169-328x(03)00134-7
复制
发表时间：
2003-06-10
期刊：
影响因子：
--
通讯作者：
Masson-Pévet, M
中科院分区：
文献类型：
--
作者：
Dardente, H;Menet, JS;Masson-Pévet, M
在哺乳动物中，相互作用的转录/翻译后反馈回路涉及“时钟基因”和它们的蛋白质产物控制昼夜节律的组织。这些基因不仅在视交叉上核（SCN）的主昼夜节律钟中表达，而且在许多外周组织中表达，在这些组织中它们表现出与SCN中所见相似但不相同的动态。在这些外周组织中，垂体的结节部（PT）表达时钟基因。我们在这里表明，大鼠的PT，像其他啮齿动物，有节奏地表达Per 1。我们还报告了另一个时钟基因Cry 1的节律表达。Cry 1 mRNA表达的高峰出现在夜间伴随着血浆褪黑激素浓度的上升。使用急性注射范例，我们表明，Cry 1的表达是直接诱导褪黑激素在PT。在主观一天结束时注射褪黑激素也会影响Per 1的表达，导致mRNA水平降低。这些数据支持存在的时间测量模型在PT的基础上直接相反的行动褪黑激素对Per 1和Cry 1的表达。2003 Elsevier Science B. V.保留所有权利。
In mammals, interacting transcriptional/ post-translational feedback loops involving 'clock genes' and their protein products control circadian organisation. These genes are not only expressed in the master circadian clock of the suprachiasmatic nuclei (SCN) but also in many peripheral tissues where they exhibit similar but not identical dynamic to that seen in the SCN. Among these peripheral tissues, the pars tuberalis (PT) of the pituitary expresses clock genes. We show here that the PT of the rat, like that of other rodents, rhythmically expresses Per1. We also report rhythmic expression of another clock gene, Cry1. The peak of Cry1 mRNA expression occurs during the night concomitantly with rising blood plasma melatonin concentrations. Using an acute injection paradigm, we demonstrate that Cry1 expression is directly induced by melatonin in the PT. Melatonin injection at the end of the subjective day also affects Per1 expression, leading to diminished mRNA levels. These data support the existence of a time-measurement model in the PT based on direct opposite actions of melatonin on Per1 and Cry1 expression. 2003 Elsevier Science B.V. All rights reserved.