title: Histone H2A has a novel variant in fish oocytes.
abstract: Histone variants and their modification have significant roles in many cellular processes. In this study, we identified and characterized the histone H2A variant h2af1o in fish and revealed its oocyte-specific expression pattern during oogenesis and embryogenesis. Moreover, posttranslational modification of H2af1o was observed that results from phosphorylation during oocyte maturation. To understand the binding dynamics of the novel core histone variant H2af1o in nucleosomes, we cloned ubiquitous gibel carp h2afx as a conventional histone control and investigated the dynamic exchange difference in chromatin by fluorescence recovery after photobleaching. H2af1o has significantly higher mobility in nucleosomes than ubiquitous H2afx. Compared with ubiquitous H2afx, H2af1o has a tightly binding C-terminal and a weakly binding N-terminal. These data indicate that fish oocytes have a novel H2A variant that destabilizes nucleosomes by protruding its N-terminal tail and stabilizes core particles by contracting its C-terminal tail. Our findings suggest that H2af1o may have intrinsic ability to modify chromatin properties during fish oogenesis, oocyte maturation, and early cleavage.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Center for Developmental Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Wuhan, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Wu
authors.forename: Hua-Mei
authors.initials: HM
authors.lastname: Yue
authors.forename: Bo
authors.initials: B
authors.lastname: Chen
authors.forename: Jian-Fang
authors.initials: JF
authors.lastname: Gui
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D036703:Blastula / Q000648:ultrastructure; D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D047108:Embryonic Development / Q000235:genetics; D005260:Female; D029941:Fish Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006054:Goldfish / Q000196:embryology / Q000378:metabolism*; D006657:Histones / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009707:Nucleosomes / Q000378:metabolism; D009865:Oocytes / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D009866:Oogenesis / Q000235:genetics; D010053:Ovary / Q000166:cytology / Q000378:metabolism; D010766:Phosphorylation; D010802:Phylogeny; D011485:Protein Binding; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016415:Sequence Alignment; D017384:Sequence Deletion; D015027:Zebrafish / Q000378:metabolism; D029961:Zebrafish Proteins / Q000378:metabolism
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; D029941:Fish Proteins; D006657:Histones; D009707:Nucleosomes; D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins; D029961:Zebrafish Proteins