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Molecular mechanism of cell-autonomous circadian gene expression of Period2, a crucial regulator of the mammalian circadian clock.

ABSTRACT: Although circadian transcription of Period2 (Per2) is fundamental for the generation of circadian rhythm, the molecular mechanism remains unclear. Here we report that cell-autonomous circadian transcription of Per2 is driven by two transcriptional elements, one for rhythm generation and the other for phase control. The former contains the E-box-like sequence (CACGTT) that is sufficient and indispensable to drive oscillation, and indeed circadian transcription factors site-specifically bind to it. Furthermore, the nature of this atypical E-box is different from that of the classical circadian E-box. The current feedback loop model is based mainly on Period1. Our results provide not only compelling evidence in support of this model but also an explanation for a general basic mechanism to produce various patterns in the phase and amplitude of cell-autonomous circadian gene expression.

SUBMITTER: Akashi M

PROVIDER: S-EPMC1356568 | biostudies-literature | 2006 Feb

REPOSITORIES: biostudies-literature

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Molecular mechanism of cell-autonomous circadian gene expression of Period2, a crucial regulator of the mammalian circadian clock.

Akashi Makoto M Ichise Tomoko T Mamine Takayoshi T Takumi Toru T

Molecular biology of the cell 20051109 2

Although circadian transcription of Period2 (Per2) is fundamental for the generation of circadian rhythm, the molecular mechanism remains unclear. Here we report that cell-autonomous circadian transcription of Per2 is driven by two transcriptional elements, one for rhythm generation and the other for phase control. The former contains the E-box-like sequence (CACGTT) that is sufficient and indispensable to drive oscillation, and indeed circadian transcription factors site-specifically bind to it ...[more]

PMID: 16280364

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