title: Inhibition of casein kinase 2 blocks G2/M transition in early embryo mitosis but not in oocyte meiosis in mouse.
abstract: Casein kinase 2 (CK2) is a highly conserved, ubiquitously expressed serine/threonine protein kinase with hundreds of substrates. The role of CK2 in the G2/M transition of oocytes, zygotes, and 2-cell embryos was studied in mouse by enzyme activity inhibition using the specific inhibitor 4, 5, 6, 7-tetrabromobenzotriazole (TBB). Zygotes and 2-cell embryos were arrested at G2phase by TBB treatment, and DNA damage was increased in the female pronucleus of arrested zygotes. Further developmental ability of arrested zygotes was reduced, but that of arrested 2-cell embryos was not affected after releasing from inhibition. By contrast, the G2/M transition in oocytes was not affected by TBB. These results indicate that CK2 activity is essential for mitotic G2/M transition in early embryos but not for meiotic G2/M transition in oocytes.
authors.affiliation: Center for Reproductive Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Shi-Bing
authors.initials: SB
authors.lastname: Cao
authors.affiliation: State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Xue-Shan
authors.initials: XS
authors.lastname: Ma
authors.affiliation: Center for Reproductive Medicine, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing 210008, China.
authors.forename: Hai-Xiang
authors.initials: HX
authors.lastname: Sun
mesh_terms: D000818:Animals; D047390:Casein Kinase II / Q000037:antagonists & inhibitors / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000502:physiology*; D005260:Female; D059565:G2 Phase Cell Cycle Checkpoints; D008813:Mice, Inbred ICR; D009865:Oocytes / Q000502:physiology*; D014230:Triazoles; D015053:Zygote / Q000201:enzymology*
chemical_list: C405354:4,5,6,7-tetrabromobenzotriazole; D014230:Triazoles; D047390:Casein Kinase II
keywords: 4, 5, 6, 7-tetrabromobenzotriazole (TBB); Casein kinase 2 (CK2); G2/M transition; Meiosis