title: Protein kinase A modulates Cdc25B activity during meiotic resumption of mouse oocytes.
abstract: Protein kinase A (PKA) play a critical role in maintaining the meiotic arrest. However, the steps downstream of PKA remain largely unknown. In this study, we investigated the regulation of meiotic resumption by PKA/Cdc25B pathway in mouse oocytes. Injection of mRNA coding for Cdc25b-S321A had a more potent maturation-inducing ability than Cdc25b-WT. When co-injected with PKA inhibitor, Cdc25B-WT had similar activities with Cdc25B-S321A. Meanwhile, the phosphorylation of Cdc25B-S321 was detected in germinal vesicle (GV) oocytes by Western blotting with a phospho-Ser321-specific antibody and the band disappeared when oocytes reenter into the meiotic cell cycle. Furthermore, Cdc25B-WT translocated to the nucleus shortly before GV breakdown (GVBD), whereas phosphorylated Cdc25B-S321 expressed exclusively in the cytoplasm and the signal could not be detected in GVBD oocytes. Taken together, these data indicate that Cdc25B-Serine321 is the potential PKA target and Cdc25B subcellular localization determines its function during the process of maintaining GV arrest in mouse oocytes.
authors.affiliation: Research Center for Medical Genomics and MOH Key Laboratory of Cell Biology, School of Medicine, China Medical University, Shenyang, Liaoning, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhang
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Xu
authors.forename: Xue-Song
authors.initials: XS
authors.lastname: Li
authors.forename: Meng
authors.initials: M
authors.lastname: Yu
authors.forename: Ai-Ming
authors.initials: AM
authors.lastname: Yu
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Zong
authors.forename: Bing-Zhi
authors.initials: BZ
authors.lastname: Yu
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004789:Enzyme Activation; D005260:Female; D016195:G2 Phase; D018507:Gene Expression Regulation, Developmental; D008540:Meiosis; D051379:Mice; D016297:Mutagenesis, Site-Directed; D009865:Oocytes / Q000166:cytology* / Q000201:enzymology*; D010766:Phosphorylation; D012694:Serine / Q000235:genetics / Q000378:metabolism; D020687:cdc25 Phosphatases / Q000235:genetics / Q000378:metabolism*
chemical_list: D012694:Serine; D017868:Cyclic AMP-Dependent Protein Kinases; C517006:Cdc25b protein, mouse; D020687:cdc25 Phosphatases