title: Specific protein kinase C isoforms α and βI are involved in follicle-stimulating hormone-induced mouse follicle-enclosed oocytes meiotic resumption.
abstract: Protein kinase C (PKC) is involved in gonadotrophin-induced oocyte maturation. In the present study, we investigated the role of specific PKC isoforms in the process of follicle-stimulating hormone (FSH)-induced oocyte meiotic resumption. Small antral follicles (200-300 µm in diameter) were isolated from immature mice and cultured in vitro. FSH significantly induced follicle-enclosed oocytes (FEOs) meiotic resumption after 8 hr culture. However, the induced effect of FSH was dose-dependently inhibited by the specific PKC α and βI inhibitor Gö6976, and 100 nM Gö6976 completely blocked FSH function in oocyte meiotic resumption. Furthermore, FSH dramatically induced the expression of transcripts encoding epidermal growth factor (EGF)-like growth factors Areg, Btc, and Ereg mRNA levels, and up-regulated tyrosine phosphorylation level of EGF receptor (EGFR) in granulosa cells. Blocking the function of EGFR by AG1478 eliminated the effect of FSH-induced FEOs meiotic resumption, suggesting that FSH induced oocyte maturation through the activation of EGFR. FSH-induced phosphorylation of EGFR could also be inhibited by Gö6976. Next, we examined the effect of FSH on the expression and phosphorylation PKC α and βI. FSH induced the expression of PKC α at mRNA and protein level, and also up-regulated its phosphorylation level in granulosa cells after 8 hr culture. However, FSH had no effect on the expression of PKC βI but down-regulated its phosphorylation level. In conclusion, FSH-induced activation of PKC α alone, or together with the inactivation of PKC βI in granulosa cells, participates in mouse oocyte meiotic resumption, possibly by the activation of EGFR signaling pathway.
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, People's Republic of China.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Wang
authors.forename: Qian
authors.initials: Q
authors.lastname: Chen
authors.forename: Jinlian
authors.initials: J
authors.lastname: Zhou
authors.forename: Jing
authors.initials: J
authors.lastname: Wen
authors.forename: Fenghua
authors.initials: F
authors.lastname: Bian
authors.forename: Ge
authors.initials: G
authors.lastname: Li
authors.forename: Xinyi
authors.initials: X
authors.lastname: Mu
authors.forename: Yingying
authors.initials: Y
authors.lastname: Han
authors.forename: Guoliang
authors.initials: G
authors.lastname: Xia
authors.forename: Meijia
authors.initials: M
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002227:Carbazoles / Q000494:pharmacology; D054751:Cyclic AMP-Dependent Protein Kinase Catalytic Subunits / Q000235:genetics / Q000378:metabolism*; D066246:ErbB Receptors / Q000378:metabolism; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008540:Meiosis / Q000187:drug effects*; D051379:Mice; D009865:Oocytes / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D006080:Ovarian Follicle / Q000166:cytology*; D010766:Phosphorylation / Q000187:drug effects; D011493:Protein Kinase C / Q000378:metabolism*; D064546:Protein Kinase C beta; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011799:Quinazolines / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020032:Tyrphostins / Q000494:pharmacology
chemical_list: D002227:Carbazoles; D007527:Isoenzymes; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D012333:RNA, Messenger; D020032:Tyrphostins; C081021:Go 6976; C101044:RTKI cpd; D005640:Follicle Stimulating Hormone; D066246:ErbB Receptors; D054751:Cyclic AMP-Dependent Protein Kinase Catalytic Subunits; C517758:Prkaca protein, mouse; D011493:Protein Kinase C; D064546:Protein Kinase C beta