title: HuCHRAC, a human ISWI chromatin remodelling complex contains hACF1 and two novel histone-fold proteins.
abstract: Chromatin remodelling complexes containing the nucleosome-dependent ATPase ISWI were first isolated from Drosophila embryos (NURF, CHRAC and ACF). ISWI was the only common component reported in these complexes. Our purification of human CHRAC (HuCHRAC) shows that ISWI chromatin remodelling complexes can have a conserved subunit composition in completely different cell types, suggesting a conserved function of ISWI. We show that the human homologues of two novel putative histone-fold proteins in Drosophila CHRAC are present in HuCHRAC. The two human histone-fold proteins form a stable complex that binds naked DNA but not nucleosomes. HuCHRAC also contains human ACF1 (hACF1), the homologue of Acf1, a subunit of Drosophila ACF. The N-terminus of mouse ACF1 was reported as a heterochromatin-targeting domain. hACF1 is a member of a family of proteins with a related domain structure that all may target heterochromatin. We discuss a possible function for HuCHRAC in heterochromatin dynamics. HuCHRAC does not contain topoisomerase II, which was reported earlier as a subunit of Drosophila CHRAC.
authors.affiliation: Marie Curie Research Institute, The Chart, Oxted, Surrey RH8 OTL, MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK.
authors.forename: R A
authors.initials: RA
authors.lastname: Poot
authors.forename: G
authors.initials: G
authors.lastname: Dellaire
authors.forename: B B
authors.initials: BB
authors.lastname: Hülsmann
authors.forename: M A
authors.initials: MA
authors.lastname: Grimaldi
authors.forename: D F
authors.initials: DF
authors.lastname: Corona
authors.forename: P B
authors.initials: PB
authors.lastname: Becker
authors.forename: W A
authors.initials: WA
authors.lastname: Bickmore
authors.forename: P D
authors.initials: PD
authors.lastname: Varga-Weisz
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D002868:Chromosomal Proteins, Non-Histone; D004258:DNA Polymerase III; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D004330:Drosophila; D029721:Drosophila Proteins; D006367:HeLa Cells; D006657:Histones / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009698:Nucleoproteins / Q000737:chemistry / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism; D011485:Protein Binding; D017510:Protein Folding; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D000092468:Bromodomain Containing Proteins
chemical_list: D000251:Adenosine Triphosphatases; D002868:Chromosomal Proteins, Non-Histone; D004258:DNA Polymerase III; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D006657:Histones; D009698:Nucleoproteins; D009707:Nucleosomes; D011994:Recombinant Proteins; D014157:Transcription Factors; C120419:Acf protein, Drosophila; C492319:BAZ1A protein, human; D000092468:Bromodomain Containing Proteins; C413904:CHRAC1 protein, human; C086468:ISWI protein; C413905:POLE3 protein, human