RT Journal Article
SR Electronic
T1 NF-κB modifies the mammalian circadian clock through interaction with the core clock protein BMAL1
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.09.06.285254
DO 10.1101/2020.09.06.285254
A1 Shen, Yang
A1 Wang, Wei
A1 Endale, Mehari
A1 Francey, Lauren J.
A1 Harold, Rachel L.
A1 Hammers, David W.
A1 Huo, Zhiguang
A1 Partch, Carrie L.
A1 Hogenesch, John B.
A1 Wu, Zhao-Hui
A1 Liu, Andrew C.
YR 2020
UL http://biorxiv.org/content/early/2020/09/06/2020.09.06.285254.abstract
AB In mammals, the circadian clock coordinates various cell physiological processes, including the inflammatory response. Recent studies suggested a crosstalk between these two pathways. However, the mechanism of how inflammation affects the circadian clock is not well understood. Here, we investigated the role of the proinflammatory transcription factor NF-κB in regulating clock function. Using a combination of genetic and pharmacological approaches, we show that perturbation of the canonical NF-κB subunit RELA in the U2OS cellular model altered core clock gene expression. While RELA activation shortened period length and dampened amplitude in these cells, its inhibition lengthened period length and caused amplitude phenotypes. NF-κB perturbation also altered circadian rhythms in the master suprachiasmatic nucleus (SCN) clock and locomotor activity. We show that RELA, like the clock repressor CRY1, potently repressed the transcriptional activity of BMAL1/CLOCK at the circadian E-box cis-element. Biochemical and biophysical analysis showed that RELA competes with coactivator CBP/p300 for binding to the transactivation domain of BMAL1. This mechanism is further supported by chromatin immunoprecipitation analysis showing that the binding sites of RELA, BMAL1 and CLOCK converge on the E-boxes of clock genes. Taken together, these data support a significant role for NF-κB in directly regulating circadian clock function and highlight mutual regulation between the circadian and inflammatory pathways.Competing Interest StatementThe authors have declared no competing interest.NF-κBnuclear factor kappa BSCNsuprachiasmatic nucleusIKKIκB kinaseIκBαinhibitor of NF-κBLucluciferaseRHDRel homology domainCRDC-terminal oscillation regulatory domainTADtransactivation domain