title: Sumoylation controls CLOCK-BMAL1-mediated clock resetting via CBP recruitment in nuclear transcriptional foci.
abstract: CLOCK-BMAL1 is a key transcription factor complex of the molecular clock system that generates circadian gene expression and physiology in mammals. Here, we demonstrate that sumoylation of BMAL1 mediates the rapid activation of CLOCK-BMAL1 by CREB-binding protein (CBP) in nuclear foci and also the resetting of the circadian clock. Under physiological conditions, a bimolecular fluorescence complementation-based fluorescence resonance energy transfer (BiFC-FRET) assay revealed that CLOCK-BMAL1 rapidly dimerized and formed a ternary complex with CBP in discrete nuclear foci in response to serum stimuli. We found that the formation of this ternary complex requires sumoylation of BMAL1 by SUMO3. These processes were abolished by both the ectopic expression of the SUMP2/3-specific protease, SUSP1, and mutation of the major sumoylation site (Lys259) of BMAL1. Moreover, molecular inhibition of BMAL1 sumoylation abrogated acute Per1 transcription and severely dampened the circadian gene oscillation triggered by clock synchronization stimuli. Taken together, these findings suggest that sumoylation plays a critical role in the spatiotemporal co-activation of CLOCK-BMAL1 by CBP for immediate-early Per induction and the resetting of the circadian clock.
authors.affiliation: Department of Brain and Cognitive Sciences and School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 151-742, Republic of Korea; Department of Pharmacology and the Institute for Translational Medicine and Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, United States.
authors.forename: Yool
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Brain and Cognitive Sciences and School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 151-742, Republic of Korea; Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 711-583, Republic of Korea.
authors.forename: Sung Kook
authors.initials: SK
authors.lastname: Chun
authors.affiliation: Department of Brain and Cognitive Sciences and School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 151-742, Republic of Korea; Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 711-583, Republic of Korea. Electronic address: kyungjin@dgist.ac.kr.
authors.forename: Kyungjin
authors.initials: K
authors.lastname: Kim
mesh_terms: D056930:ARNTL Transcription Factors / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D056926:CLOCK Proteins / Q000235:genetics / Q000378:metabolism*; D019556:COS Cells; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism*; D002522:Chlorocebus aethiops; D057906:Circadian Clocks / Q000502:physiology*; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000378:metabolism; D006801:Humans; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism*; D012795:Sialoglycoproteins / Q000235:genetics / Q000378:metabolism*; D058207:Sumoylation / Q000502:physiology*; D014452:Ubiquitins / Q000235:genetics / Q000378:metabolism
chemical_list: D056930:ARNTL Transcription Factors; C538960:BMAL1 protein, human; D010446:Peptide Fragments; C492189:SUMO3 protein, human; D012795:Sialoglycoproteins; D014452:Ubiquitins; C571744:bone sialoprotein (35-62), human; D056926:CLOCK Proteins; C538943:CLOCK protein, human; D003546:Cysteine Endopeptidases; C408873:SENP6 protein, human
keywords: BMAL1; BiFC-based FRET; CBP; Circadian clock; Clock resetting; Nuclear body; SUSP1; Sumoylation