Protein tyrosine kinase signaling in the mouse oocyte cortex during spermegg interactions and anaphase resumption
Protein tyrosine kinase signaling in the mouse oocyte cortex during spermegg interactions and anaphase resumption
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DOI：
10.1002/mrd.22160
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发表时间：
2013-04-01
影响因子：
2.5
通讯作者：
Kinsey, William H.
中科院分区：
文献类型：
--
作者：
McGinnis, Lynda K.;Luo, Jinping;Kinsey, William H.
受精触发卵母细胞中一系列预编程信号转导途径的激活，这些信号转导途径建立多精受精的阻断，诱导减数分裂恢复，并启动合子发育。精子和卵母细胞之间的融合导致卵母细胞内游离钙水平的快速变化，这反过来又激活了卵质中的多个蛋白激酶级联反应。本研究探讨了精母细胞相互作用涉及卵母细胞蛋白酪氨酸激酶的局部激活的可能性，这可能提供了一种替代的信号传导机制，触发的精子。用磷酸酪氨酸和磷酸化蛋白酪氨酸激酶的抗体进行共聚焦免疫荧光分析，可以检测到定位于精母细胞相互作用位点的微小信号事件，这些事件不适合生化分析。结果提供了证据，磷酸酪氨酸在精子接触，结合或融合的网站，这表明活性蛋白酪氨酸激酶信号之前和精子结合过程中的局部积累。发现PYK2激酶在精母细胞相互作用的位点被浓缩和激活，并且可能参与这种反应。随后在卵母细胞皮质内观察到PYK2和FAK激酶的广泛激活，表明精子掺入之后是减数分裂恢复期间通过这些激酶的更多全局信号传导。结果表明，在哺乳动物卵母细胞中，精子与卵母细胞接触、结合或融合触发了另一种信号通路。摩尔Reprod. Dev. 80：260272，2013。(c)2013 Wiley Periodicals，Inc.
Fertilization triggers activation of a series of pre-programmed signal transduction pathways in the oocyte that establish a block to polyspermy, induce meiotic resumption, and initiate zygotic development. Fusion between sperm and oocyte results in rapid changes in oocyte intracellular free-calcium levels, which in turn activate multiple protein kinase cascades in the ooplasm. The present study examined the possibility that spermoocyte interaction involves localized activation of oocyte protein tyrosine kinases, which could provide an alternative signaling mechanism to that triggered by the fertilizing sperm. Confocal immunofluorescence analysis with antibodies to phosphotyrosine and phosphorylated protein tyrosine kinases allowed detection of minute signaling events localized to the site of spermoocyte interaction that were not amenable to biochemical analysis. The results provide evidence for localized accumulation of phosphotyrosine at the site of sperm contact, binding, or fusion, which suggests active protein tyrosine kinase signaling prior to and during sperm incorporation. The PYK2 kinase was found to be concentrated and activated at the site of spermoocyte interaction, and likely participates in this response. Widespread activation of PYK2 and FAK kinases was subsequently observed within the oocyte cortex, indicating that sperm incorporation is followed by more global signaling via these kinases during meiotic resumption. The results demonstrate an alternate signaling pathway triggered in mammalian oocytes by sperm contact, binding, or fusion with the oocyte. Mol. Reprod. Dev. 80: 260272, 2013. (c) 2013 Wiley Periodicals, Inc.