title: A novel role for the histone acetyltransferase Hat1 in the CENP-A/CID assembly pathway in Drosophila melanogaster.
abstract: The incorporation of CENP-A into centromeric chromatin is an essential prerequisite for kinetochore formation. Yet, the molecular mechanisms governing this process are surprisingly divergent in different organisms. While CENP-A loading mechanisms have been studied in some detail in mammals, there are still large gaps to our understanding of CENP-A/Cid loading pathways in Drosophila. Here, we report on the characterization and delineation of at least three different CENP-A preloading complexes in Drosophila. Two complexes contain the CENP-A chaperones CAL1, FACT and/or Caf1/Rbap48. Notably, we identified a novel complex consisting of the histone acetyltransferase Hat1, Caf1 and CENP-A/H4. We show that Hat1 is required for proper CENP-A loading into chromatin, since knock-down in S2 cells leads to reduced incorporation of newly synthesized CENP-A. In addition, we demonstrate that CENP-A/Cid interacts with the HAT1 complex via an N-terminal region, which is acetylated in cytoplasmic but not in nuclear CENP-A. Since Hat1 is not responsible for acetylation of CENP-A/Cid, these results suggest a histone acetyltransferase activity-independent escort function for Hat1. Thus, our results point toward intriguing analogies between the complex processing pathways of newly synthesized CENP-A and canonical histones.
authors.affiliation: Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria.
authors.forename: Mark
authors.initials: M
authors.lastname: Boltengagen
authors.affiliation: Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria.
authors.forename: Anming
authors.initials: A
authors.lastname: Huang
authors.affiliation: Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria.
authors.forename: Anastasiya
authors.initials: A
authors.lastname: Boltengagen
authors.affiliation: Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria.
authors.forename: Lukas
authors.initials: L
authors.lastname: Trixl
authors.affiliation: Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria.
authors.forename: Herbert
authors.initials: H
authors.lastname: Lindner
authors.affiliation: Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria.
authors.forename: Leopold
authors.initials: L
authors.lastname: Kremser
authors.affiliation: Division of Neurobiochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Offterdinger
authors.affiliation: Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria alexandra.lusser@i-med.ac.at.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Lusser
mesh_terms: D000107:Acetylation; D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure; D000076247:Centromere Protein A; D002843:Chromatin / Q000378:metabolism* / Q000648:ultrastructure; D003593:Cytoplasm / Q000378:metabolism / Q000648:ultrastructure; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D004331:Drosophila melanogaster / Q000166:cytology / Q000378:metabolism*; D005786:Gene Expression Regulation; D051548:Histone Acetyltransferases / Q000235:genetics* / Q000378:metabolism; D006657:Histones / Q000235:genetics* / Q000378:metabolism; D018386:Kinetochores / Q000378:metabolism* / Q000648:ultrastructure; D008969:Molecular Sequence Data; D010957:Plasmids / Q000737:chemistry / Q000378:metabolism; D056505:Retinoblastoma-Binding Protein 4 / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection
chemical_list: C110251:Caf1-55 protein, Drosophila; C558282:Cal1 protein, Drosophila; D002352:Carrier Proteins; D000076247:Centromere Protein A; D002843:Chromatin; C427237:Cid protein, Drosophila; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C518656:FACT protein, Drosophila; D006657:Histones; D056505:Retinoblastoma-Binding Protein 4; D051548:Histone Acetyltransferases; C110880:histone acetyltransferase type B complex