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Published on: January 26, 2018
CLOCK leaves its mark on histones
William J Belden1, Jennifer J Loros, Jay C Dunlap
1Department of Genetics, Dartmouth Medical School, Hanover, NH 03755, USA.
Abstract:
Transcriptional regulation of circadian rhythms in mammals involves a negative-feedback loop whereby a CLOCK-BMAL1 complex activates transcription of the genes encoding the proteins PER1 (Period 1), PER2, CRY1 (Cryptochrome 1) and CRY2, which feed back to inhibit the activity of CLOCK-BMAL1. It is becoming evident that chromatin remodeling has a crucial role in the transcriptional regulation of genes governing circadian rhythms. This is highlighted in a recent report that shows that CLOCK has histone acetyltransferase activity, thus, demonstrating that molecular components of the biological clock can themselves catalyze chromatin modifications.
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