文章基本信息

标题：CLOCK:BMAL-Independent Circadian Oscillation of Zebrafish Cryptochrome1a Gene
本地全文：下载
作者：Norio Miyamura ; Jun Hirayama ; Kenji Sawanobori 等
期刊名称：Biological and Pharmaceutical Bulletin
印刷版ISSN：0918-6158
电子版ISSN：1347-5215
出版年度：2009
卷号：32
期号：7
页码：1183-1187
DOI：10.1248/bpb.32.1183
出版社：The Pharmaceutical Society of Japan
摘要：In the vertebrate circadian feedback loop, CLOCK:BMAL heterodimers induce the expression of Cry genes. The CRY proteins in turn inhibit CLOCK:BMAL-mediated transcription closing the negative feedback loop. Four CRYs, which all inhibit CLOCK:BMAL-mediated transcription, exist in zebrafish. Although these zebrafish Cry s ( zCry1a , 1b , 2a , and 2b ) show a circadian pattern of expression, previous studies have indicated that the circadian oscillation of zCry1a could be CLOCK:BMAL-independent. Here we show that abrogation of CLOCK:BMAL-dependent transcription in zebrafish cells by the dominant negative zCLOCK3-DeltaC does not affect the circadian oscillation of zCry1a . Moreover, we provide several lines of evidence indicating that the extracellular signal-regulated kinase (ERK) signaling cascade modulates the circadian expression of zCry1a gene in constant darkness. Taken together, our data strongly support the notion that circadian oscillation of zCry1a is CLOCK:BMAL-independent and further indicate that mechanisms involving non-canonical clock genes could contribute to the circadian expression of zCry1a gene in a cell autonomous manner.
关键词：circadian clock;cryptochrome;transcription