title: Histone chaperone FACT action during transcription through chromatin by RNA polymerase II.
abstract: FACT (facilitates chromatin transcription) is a histone chaperone that promotes chromatin recovery during transcription, with additional roles in cell differentiation. Although several models of the action of FACT during transcription have been proposed, they remain to be experimentally evaluated. Here we show that human FACT (hFACT) facilitates transcription through chromatin and promotes nucleosome recovery in vitro. FACT action depends on the presence of histone H2A/H2B dimers in the nucleosome. Kinetic analysis suggests that hFACT decreases the lifetime of nonproductive RNA polymerase II (Pol II)-nucleosome complexes and facilitates the formation of productive complexes containing nucleosomal DNA partially uncoiled from the octamer. Taken together, our data suggest that hFACT interacts with DNA-binding surfaces of H2A/H2B dimers, facilitating uncoiling of DNA from the histone octamer. Thus, hFACT-H2A/H2B interactions play a key role in overcoming the nucleosomal barrier by Pol II and promoting nucleosome survival during transcription.
authors.affiliation: Department of Pharmacology, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
authors.forename: Fu-Kai
authors.initials: FK
authors.lastname: Hsieh
authors.forename: Olga I
authors.initials: OI
authors.lastname: Kulaeva
authors.forename: Smita S
authors.initials: SS
authors.lastname: Patel
authors.forename: Pamela N
authors.initials: PN
authors.lastname: Dyer
authors.forename: Karolin
authors.initials: K
authors.lastname: Luger
authors.forename: Danny
authors.initials: D
authors.lastname: Reinberg
authors.forename: Vasily M
authors.initials: VM
authors.lastname: Studitsky
mesh_terms: D002843:Chromatin / Q000737:chemistry*; D003432:Cross-Linking Reagents; D004247:DNA / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000378:metabolism*; D019281:Dimerization; D005786:Gene Expression Regulation; D006609:High Mobility Group Proteins / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D009154:Mutation; D009707:Nucleosomes / Q000378:metabolism; D012319:RNA Polymerase II / Q000378:metabolism*; D014158:Transcription, Genetic; D035602:Transcriptional Elongation Factors / Q000378:metabolism*
chemical_list: D002843:Chromatin; D003432:Cross-Linking Reagents; D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; D006657:Histones; D009707:Nucleosomes; C073537:SSRP1 protein, human; D035602:Transcriptional Elongation Factors; D004247:DNA; D012319:RNA Polymerase II
keywords: DNA uncoiling; dynamics; elongation; mechanism