CLOCK Stabilizes CYCLE to Initiate Clock Function in
Overview
Affiliations
The circadian clock keeps time via transcriptional feedback loops. These feedback loops are initiated by CLOCK-CYCLE (CLK-CYC) heterodimers, which activate transcription of genes encoding the feedback repressors PERIOD and TIMELESS. Circadian clocks normally operate in ∼150 brain pacemaker neurons and in many peripheral tissues in the head and body, but can also be induced by expressing CLK in nonclock cells. These ectopic clocks also require , yet CYC expression is restricted to canonical clock cells despite evidence that mRNA is widely expressed. Here we show that CLK binds to and stabilizes CYC in cell culture and in nonclock cells in vivo. Ectopic clocks also require the blue light photoreceptor CRYPTOCHROME (CRY), which is required for both light entrainment and clock function in peripheral tissues. These experiments define the genetic architecture required to initiate circadian clock function in , reveal mechanisms governing circadian activator stability that are conserved in perhaps all eukaryotes, and suggest that , , and expression is sufficient to drive clock expression in naive cells.
Alternative splicing of transcript mediates the response of circadian clocks to temperature changes.
Cai Y, Liu X, Chow G, Hidalgo S, Jackson K, Vasquez C Proc Natl Acad Sci U S A. 2024; 121(50):e2410680121.
PMID: 39630861 PMC: 11648895. DOI: 10.1073/pnas.2410680121.
The Drosophila circadian clock gene cycle controls the development of clock neurons.
Biondi G, McCormick G, Fernandez M PLoS Genet. 2024; 20(10):e1011441.
PMID: 39432537 PMC: 11527286. DOI: 10.1371/journal.pgen.1011441.
Alternative splicing of transcript mediates the response of circadian clocks to temperature changes.
Cai Y, Chow G, Hidalgo S, Liu X, Jackson K, Vasquez C bioRxiv. 2024; .
PMID: 38766142 PMC: 11100826. DOI: 10.1101/2024.05.10.593646.
Ma D, Ojha P, Yu A, Araujo M, Luo W, Keefer E Proc Natl Acad Sci U S A. 2024; 121(15):e2321338121.
PMID: 38568969 PMC: 11009632. DOI: 10.1073/pnas.2321338121.
Zhang H, Zhou Z, Guo J Int J Mol Sci. 2024; 25(5).
PMID: 38473819 PMC: 10931572. DOI: 10.3390/ijms25052574.