title: The nuclear Hat1p/Hat2p complex: a molecular link between type B histone acetyltransferases and chromatin assembly.
abstract: The yeast Hat1p/Hat2p type B histone acetyltransferase complex is localized to both the cytoplasm and nucleus. We isolate the nuclear form of the Hat1p/Hat2p complex and find that it copurifies with the product of the uncharacterized open reading frame YLL022C (named Hif1p). The functional significance of the association of Hif1p with the Hat1p/Hat2p complex is confirmed by the observation that hif1Delta and hat1Delta strains display similar defects in telomeric silencing and DNA double-strand break repair. Hif1p is a histone chaperone that selectively interacts with histones H3 and H4. Hif1p is also a chromatin assembly factor, promoting the deposition of histones in the presence of a yeast cytosolic extract. In vivo, the nuclear Hat1p/Hat2p/Hif1p complex is bound to acetylated histone H4, as well as histone H3. The association of Hif1p with acetylated H4 requires Hat1p and Hat2p providing a link between type B histone acetyltransferases and chromatin assembly.
authors.affiliation: Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Xi
authors.initials: X
authors.lastname: Ai
authors.forename: Mark R
authors.initials: MR
authors.lastname: Parthun
mesh_terms: D000123:Acetyltransferases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000483:Alleles; D015153:Blotting, Western; D002457:Cell Extracts; D002467:Cell Nucleus / Q000737:chemistry / Q000201:enzymology*; D002843:Chromatin / Q000378:metabolism*; D003593:Cytoplasm / Q000737:chemistry; D004249:DNA Damage; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D019084:Fluorescent Antibody Technique, Indirect; D017353:Gene Deletion; D020868:Gene Silencing; D017930:Genes, Reporter; D051548:Histone Acetyltransferases; D051793:Hypoxia-Inducible Factor 1; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000378:metabolism; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism; D016366:Open Reading Frames; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D013347:Subcellular Fractions; D013379:Substrate Specificity; D016615:Telomere / Q000378:metabolism; D014157:Transcription Factors
chemical_list: D002457:Cell Extracts; D002843:Chromatin; D004268:DNA-Binding Proteins; D051793:Hypoxia-Inducible Factor 1; D018832:Molecular Chaperones; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D000123:Acetyltransferases; D051548:Histone Acetyltransferases