title: Drosophila TAP/p32 is a core histone chaperone that cooperates with NAP-1, NLP, and nucleophosmin in sperm chromatin remodeling during fertilization.
abstract: Nuclear DNA in the male gamete of sexually reproducing animals is organized as sperm chromatin compacted primarily by sperm-specific protamines. Fertilization leads to sperm chromatin remodeling, during which protamines are expelled and replaced by histones. Despite our increased understanding of the factors that mediate nucleosome assembly in the nascent male pronucleus, the machinery for protamine removal remains largely unknown. Here we identify four Drosophila protamine chaperones that mediate the dissociation of protamine-DNA complexes: NAP-1, NLP, and nucleophosmin are previously characterized histone chaperones, and TAP/p32 has no known function in chromatin metabolism. We show that TAP/p32 is required for the removal of Drosophila protamine B in vitro, whereas NAP-1, NLP, and Nph share roles in the removal of protamine A. Embryos from P32-null females show defective formation of the male pronucleus in vivo. TAP/p32, similar to NAP-1, NLP, and Nph, facilitates nucleosome assembly in vitro and is therefore a histone chaperone. Furthermore, mutants of P32, Nlp, and Nph exhibit synthetic-lethal genetic interactions. In summary, we identified factors mediating protamine removal from DNA and reconstituted in a defined system the process of sperm chromatin remodeling that exchanges protamines for histones to form the nucleosome-based chromatin characteristic of somatic cells.
authors.affiliation: Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Emelyanov
authors.affiliation: Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Rabbani
authors.affiliation: Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
authors.forename: Monika
authors.initials: M
authors.lastname: Mehta
authors.affiliation: Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
authors.forename: Elena
authors.initials: E
authors.lastname: Vershilova
authors.affiliation: Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Keogh
authors.affiliation: Department of Cell Biology, Albert Einstein College of Medicine, Bronx, New York 10461, USA dmitry.fyodorov@einstein.yu.edu.
authors.forename: Dmitry V
authors.initials: DV
authors.lastname: Fyodorov
mesh_terms: D000818:Animals; D042002:Chromatin Assembly and Disassembly / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005306:Fertilization / Q000502:physiology*; D056488:Histone Chaperones / Q000378:metabolism; D008297:Male; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D000090243:Nucleophosmin; D056489:Nucleoplasmins / Q000235:genetics / Q000378:metabolism*; D056490:Nucleosome Assembly Protein 1 / Q000235:genetics / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D013094:Spermatozoa / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; D056488:Histone Chaperones; C112502:MAM33 protein, S cerevisiae; D024101:Mitochondrial Proteins; C533554:Nap1 protein, Drosophila; D009479:Neuropeptides; C533549:Nlp protein, Drosophila; D009687:Nuclear Proteins; D056489:Nucleoplasmins; D056490:Nucleosome Assembly Protein 1; D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins; C107036:Tap protein, Drosophila; D014157:Transcription Factors; D000090243:Nucleophosmin
keywords: chromatin assembly; fertilization; histone chaperones; male pronucleus; protamines; sperm chromatin remodeling