The role of MAP kinase cascade in activation of porcine oocytes

MAP激酶级联在猪卵母细胞激活中的作用

• 批准号: 10660271
• 负责人: TERADA Takato
• 金额: $ 2.24万
• 依托单位: Hiroshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10660271/
• 关键词: pig; oocyte; MAP kinase; activation; cumulus cell; gap junction; PI 3-kinase 8 MPF; MPF; PI3-kinase; ブタ卵子; MEK inhibitor; 卵子の活性化; コネキシン

The role of MAP kinase during maturation of porcine oocytes and the activation mechanisms were explored. MAP kinase in the oocytes was dramatically activated in metaphase I and the activated MAP kinase led to activation of MPF. These results suggest that the activation of MAP kinase is essential for the normal progression into the metaphase of the second meiosis. Further, the evidences that MAP kinase activation in oocytes were completely dependent on the activity of PI 3-kinase in the surrounding cumulus cells, inducing a shutdown of the gap junctions between oocytes and cumulus cells, were provided. Next, zona reaction which is an indicator of CaィイD12+ィエD1 transients at oocyte activation was assessed. The procedure for detecting a modification of glycoproteins in zona pellucida of a single oocyte, was devised. Using this procedure, it was demonstrated that the MPF activity declined quickly in oocytes activated by CaィイD12+ィエD1 ionophore at low concentration, but the activity of MAP ki … More nase remained high, resulting in reactivation of MPF and the oocyte progression into the MIII stage, which is considered to be the abnormal event. Moreover, the combined treatment with CaィイD12+ィエD1 ionophore at low concentration and specific MEK inhibitor, U0126, resulted in dramatic drop in activities of MPF and MAP kinase, and subsequently activities of both kinase was maintained at the basal level until the development of a pronucleus was induced in the oocytes. These findings clearly demonstrate that maintaining the reduced activity of MPF due to the decline of MAP kinase activity is critical for completion of meiotic maturation and the formation of pronuclei in porcine oocytes. Taken together, the following conclusions can be drown from this study ; 1) The activity of MAP kinase is porcine oocytes is regulated by the surrounding cumulus cells. 2) The activation of MAP kinase is a prerequisite for the progression beyond metaphase I into metaphase II. 3) MAP kinase is inactivated by elevation of CaィイD12+ィエD1 in MII arrested oocytes, which is closely associated with completion of meiosis and formation of pronuclei. Less

探讨了MAPK在猪卵母细胞成熟过程中的作用及其激活机制。卵母细胞中的MAP激酶在中期I被显著激活，激活的MAP激酶导致MPF的激活。这些结果表明，MAP激酶的激活对于进入第二次减数分裂中期的正常进行是必不可少的。此外，还提供了卵母细胞中MAPK的激活完全依赖于周围卵丘细胞中的PI3-激酶活性的证据，从而导致卵母细胞与卵丘细胞之间的缝隙连接关闭。接下来，评估了卵母细胞激活时的小带反应，它是CaィイD12+ィエD1瞬变的指示器。设计了检测单个卵母细胞透明带糖蛋白修饰的方法。结果表明，在低浓度CaィイD12+ィエD1离子载体激活的卵母细胞中，mpf活性迅速下降，而MAP Ki…活性下降。更多的Nase处于高水平，导致MPF重新激活，卵母细胞进入MIII期，这被认为是异常事件。此外，低浓度的CaィイD12+MEKD 1离子载体和特异性ィエ抑制剂U0126联合处理后，MPF和MAPK的活性显著降低，随后这两种蛋白的活性都维持在基础水平，直到诱导卵母细胞发育成原核。这些发现清楚地表明，维持由于MAP激酶活性下降而导致的MPF活性降低对于猪卵母细胞完成减数分裂成熟和形成原核是至关重要的。综上所述，本研究得出以下结论：1)猪卵母细胞MAP的活性受周围卵丘细胞的调节。3)MII期受阻卵母细胞中CaィイD12+ィエD1的升高使MAP激酶失活，这与减数分裂的完成和原核的形成密切相关。较少

项目成果

M.Shimada and T.Terda: "Phosphorylation of connexin-43,gap junctional protein,in cumulus cells is regulated by mitogen-actibated protein kinase and phosphatisylinositol 3-kinase during in vitro meiotic resumption in porcine follicular oocytes"J.Mamm.Ova R

M.Shimada 和 T.Terda：“在猪滤泡卵母细胞体外减数分裂恢复过程中，卵丘细胞中连接蛋白 43（缝隙连接蛋白）的磷酸化受到丝裂原激活蛋白激酶和磷脂酰肌醇 3-激酶的调节”J.Mamm.Ova

H.Tatemoto and T.Terda: "Time course analysis of contical granule exocytosis and pellucida modification after artificial activation in in-vitro matured porcine oocytes"J.Mamm.Ova Res.. 16(3). 110-117 (1999)

H.Tatemoto 和 T.Terda：“体外成熟猪卵母细胞人工激活后圆锥颗粒胞吐作用和透明修饰的时间过程分析”J.Mamm.Ova Res.. 16(3)。

M.Shimada: "Effects of phosphatidylinositol 3-kinase inhibitors, wortmannin and LY294002, on germinal vesicle breakdown (GVBD) in porcine cocytes" Journal of Reproduction and Development. 44(3). 281-288 (1998)

M.Shimada：“磷脂酰肌醇 3-激酶抑制剂、渥曼青霉素和 LY294002 对猪母细胞生发囊泡分解 (GVBD) 的影响”《生殖与发育杂志》。

Shimada M., Idris M.A. and Terada T.: "Effects of Phosphatidylinositol 3-Kinase Inhibitors, Wortmannin and LY294002 on Germinal Vesicle Breakdown (GVBD) in Porcine Oocytes."J. Reprod. Dev.. vol. 44. 281-288 (1998)

Shimada M.、Idris M.A. 和 Terada T.：“磷脂酰肌醇 3-激酶抑制剂、渥曼青霉素和 LY294002 对猪卵母细胞生发囊泡分解 (GVBD) 的影响。”

Shimada M., Idris M.A. and Terada T.: "Phosphatidylinositol 3-Kinase in Cumulus Cells is Responsible for Meiotic Progression from M I to M II Stage in Porcine Follicular Oocytes."J. Mamm. Ova Res.. Vol. 15. 68-76 (1998)

Shimada M.、Idris M.A. 和 Terada T.：“卵丘细胞中的磷脂酰肌醇 3-激酶负责猪卵泡卵母细胞从 M I 阶段到 M II 阶段的减数分裂进展”。