title: H3 Thr3 phosphorylation is crucial for meiotic resumption and anaphase onset in oocyte meiosis.
abstract: Haspin-catalyzed histone H3 threonine 3 (Thr3) phosphorylation facilitates chromosomal passenger complex (CPC) docking at centromeres, regulating indirectly chromosome behavior during somatic mitosis. It is not fully known about the expression and function of H3 with phosphorylated Thr3 (H3T3-P) during meiosis in oocytes. In this study, we investigated the expression and sub-cellular distribution of H3T3-P, as well as its function in mouse oocytes during meiotic division. Western blot analysis revealed that H3T3-P expression was only detected after germinal vesicle breakdown (GVBD), and gradually increased to peak level at metaphase I (MI), but sharply decreased at metaphase II (MII). Immunofluorescence showed H3T3-P was only brightly labeled on chromosomes after GVBD, with relatively high concentration across the whole chromosome axis from pro-metaphase I (pro-MI) to MI. Specially, H3T3-P distribution was exclusively limited to the local space between sister centromeres at MII stage. Haspin inhibitor, 5-iodotubercidin (5-ITu), dose- and time-dependently blocked H3T3-P expression in mouse oocytes. H3T3-P inhibition delayed the resumption of meiosis (GVBD) and chromatin condensation. Moreover, the loss of H3T3-P speeded up the meiotic transition to MII of pro-MI oocytes in spite of the presence of non-aligned chromosomes, even reversed MI-arrest induced with Nocodazole. The inhibition of H3T3-P expression distinguishably damaged MAD1 recruitment on centromeres, which indicates the spindle assembly checkpoint was impaired in function, logically explaining the premature onset of anaphase I. Therefore, Haspin-catalyzed histone H3 phosphorylation is essential for chromatin condensation and the following timely transition from meiosis I to meiosis II in mouse oocytes during meiotic division.
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Haojie
authors.initials: H
authors.lastname: Wei
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Juan
authors.initials: J
authors.lastname: Du
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Cao
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Nana
authors.initials: N
authors.lastname: Zhang
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Liu
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Liu
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Chen
authors.affiliation: a Department of Histology and Embryology , School of Basic Medical Sciences, Capital Medical University , Beijing , China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ma
mesh_terms: D000818:Animals; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002503:Centromere / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D002843:Chromatin / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D042002:Chromatin Assembly and Disassembly / Q000187:drug effects; D054885:Cumulus Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D006657:Histones / Q000235:genetics* / Q000378:metabolism; D008540:Meiosis / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008938:Mitosis / Q000187:drug effects; D015739:Nocodazole / Q000494:pharmacology; D009865:Oocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D015398:Signal Transduction; D013912:Threonine / Q000378:metabolism*; D013997:Time Factors; D014372:Tubercidin / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D018797:Cell Cycle Proteins; D002843:Chromatin; D006657:Histones; C034214:5-iodotubercidin; D013912:Threonine; D014372:Tubercidin; D015739:Nocodazole
keywords: GVBD; H3T3-P; MAD1; meiotic progression; oocytes