Circadian Oscillation ofBMAL1,a Partner of a Mammalian Clock GeneClock,in Rat Suprachiasmatic Nucleus

doi:10.1006/bbrc.1998.9275

Biochemical and Biophysical Research Communications

Volume 250, Issue 1, 8 September 1998, Pages 83-87

https://doi.org/10.1006/bbrc.1998.9275 Get rights and content

Abstract

A superfamily gene which encodes a bHLH (basic helix-loop-helix)/PAS transcription factor,BMAL1,was cloned and sequenced from rat cDNA. A robust circadian rhythm of ratBMAL1expression was detected byin situhybridization in the suprachiasmatic nucleus (SCN), the site of the circadian clock, with the highest level at the subjective night. Less prominent and completely reversed circadian rhythms ofrBMAL1mRNA were observed in the piriform and parietal cortices. The hybridization signals ofrBMAL1mRNA were also detected in the olfactory bulb, hippocampus, and cerebellum. Since the product ofrBMAL1was recently demonstrated to dimerize with the protein of a mammalian clock gene,Clock,and the protein complex was shown to bind the E Box in the promoter region ofmPer1(a mouse homologue toDrosophilaclock gene,Per),rBMAL1possibly plays a critical role in the clock mechanism generating the circadian oscillation in rats.

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^☆: The nucleotide sequence of ratBMAL1will appear in the DDBJ, EMBL, and GenBank nucleotide sequence databases under Accession No. AB012600.

²: To whom correspondence and reprint requests should be addressed. Fax: 81-11-706-7871. E-mail:[email protected].

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Regular ArticleCircadian Oscillation ofBMAL1,a Partner of a Mammalian Clock GeneClock,in Rat Suprachiasmatic Nucleus☆

Abstract

Regular Article
Circadian Oscillation ofBMAL1,a Partner of a Mammalian Clock GeneClock,in Rat Suprachiasmatic Nucleus☆