title: Methylation of histone H3 on lysine 4 by the lysine methyltransferase SET1 protein is needed for normal clock gene expression.
abstract: The circadian oscillator controls time-of-day gene expression by a network of interconnected feedback loops and is reset by light. The requisite for chromatin regulation in eukaryotic transcription necessitates temporal regulation of histone-modifying and chromatin-remodeling enzymes for proper clock function. CHD1 is known to bind H3K4me3 in mammalian cells, and Neurospora CHD1 is required for proper regulation of the frequency (frq) gene. Based on this, we examined a strain lacking SET1 to determine the role of H3K4 methylation in clock- and light-mediated frq regulation. Expression of frq was altered in strains lacking set1 under both circadian- and light-regulated gene expression. There is a delay in the phasing of H3K4me3 relative to the peak in frq expression. White Collar 2 (WC-2) association with the frq promoter persists longer in Δset1, suggesting a more permissible chromatin state. Surprisingly, SET1 is required for DNA methylation in the frq promoter, indicating a dependence on H3K4me for DNA methylation. The data support a model where SET1 is needed for proper regulation by modulating chromatin at frq.
authors: Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901.
authors: Hamidah
authors: H
authors: Raduwan
authors: Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901.
authors: Allison L
authors: AL
authors: Isola
authors: Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901. Electronic address: belden@aesop.rutgers.edu.
authors: William J
authors: WJ
authors: Belden
mesh_terms: D002940:Circadian Rhythm; D019175:DNA Methylation; D004268:DNA-Binding Proteins / Q000378:metabolism; D044127:Epigenesis, Genetic; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D015966:Gene Expression Regulation, Fungal / Q000528:radiation effects; D055786:Gene Knockout Techniques; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D006657:Histones / Q000378:metabolism*; D008027:Light; D008745:Methylation; D009492:Neurospora crassa / Q000201:enzymology* / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D011499:Protein Processing, Post-Translational; D013172:Spores, Fungal / Q000201:enzymology / Q000235:genetics / Q000502:physiology / Q000528:radiation effects; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; C087405:FRQ protein, Neurospora crassa; D005656:Fungal Proteins; D006657:Histones; D014157:Transcription Factors; C103772:white collar 2 protein, Neurospora; D011495:Histone-Lysine N-Methyltransferase