title: Spt6 prevents transcription-coupled loss of posttranslationally modified histone H3.
abstract: The tail of histone H3 is an ideal medium for storing epigenetic information because displacement of histone H3 is heavily restricted during transcription. To maintain the locus-specific modifications of histone H3, histone molecules should be retained locally at the original position through multiple rounds of transcription. Here, we found that fission yeast Spt6, a highly conserved RNA polymerase II-interacting histone H3-H4 chaperone, is essential for the maintenance of Lys-4 and Lys-9 methylation of histone H3 in euchromatin and heterochromatin, respectively. In euchromatin, loss of Lys-4 methylated histone H3 and deposition of newly synthesized Lys-56 acetylated histone H3 induced by Spt6 inactivation were coupled with transcription. While in heterochromatin, Spt6 prevents histone turnover and cryptic transcription in parallel with Clr3 histone deacetylase. We propose that Spt6 retains posttranslationally modified histone H3 during transcription to maintain epigenome integrity.
authors.affiliation: Department of Biochemistry, Shimane University School of Medicine, Izumo, Japan. hkato@med.shimane-u.ac.jp
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kato
authors.forename: Kosuke
authors.initials: K
authors.lastname: Okazaki
authors.forename: Tetsushi
authors.initials: T
authors.lastname: Iida
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Nakayama
authors.forename: Yota
authors.initials: Y
authors.lastname: Murakami
authors.forename: Takeshi
authors.initials: T
authors.lastname: Urano
mesh_terms: D000107:Acetylation; D018797:Cell Cycle Proteins / Q000378:metabolism; D023061:Gene Order; D006570:Heterochromatin / Q000235:genetics / Q000378:metabolism; D056488:Histone Chaperones / Q000235:genetics / Q000378:metabolism*; D006655:Histone Deacetylases / Q000378:metabolism; D006657:Histones / Q000235:genetics* / Q000378:metabolism*; D008239:Lysine / Q000378:metabolism; D008745:Methylation; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D009707:Nucleosomes / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D018797:Cell Cycle Proteins; C115302:Clr3 protein, S pombe; D006570:Heterochromatin; D056488:Histone Chaperones; D006657:Histones; D009707:Nucleosomes; D029702:Schizosaccharomyces pombe Proteins; C585902:Spt6 protein, S pombe; D006655:Histone Deacetylases; D008239:Lysine