ROLE OF EGF IN MAMMALIAN EMBRYOS

EGF 在哺乳动物胚胎中的作用

• 批准号: 6281115
• 负责人: DAVID GROSS
• 金额: $ 1.83万
• 依托单位: MARINE BIOLOGICAL LABORATORY
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-12-01 至 1998-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6281115
• 关键词: Mammalia; bioengineering /biomedical engineering; biomedical equipment development; biomedical resource; clinical research; growth /development; mother /infant health care; reproductive system; technology /technique; women's health

The aim of our visit was to examine the role of epidermal growth factor (EGF) activation of the EGF receptor (EGFR) in stimulating Ca ion fluxes in mouse oocytes and embryos. We know that the EGFR is expressed in both the oocyte and its attendant cumulus cells in a stage-dependent manner. Likewise, the EGFR is also expressed in embryos. EGF has been shown to be an important factor that promotes in vitro development of oocytes and embryos. Additionally, the EGFR is known in tissue culture cells to activate the release of Ca from intracellular stores via a phospholipase C-dependent pathway. Our specific focus is on putative coupling between this EGFR-mediated Ca release and potential stimulated efflux of Ca. Preliminary data showed that in all cumulus-oocyte complexes (COCs) tested (N=3), a strong EGF-stimulated Ca efflux was found. Surprisingly, we found that oscillations of Ca efflux with a period of 2-4 min were seen in COCs, suggesting that a dominant frequency generator regulates these oscillations in these gap junction-coupled cell complexes. Significantly, cumulus cell-free oocytes showed only an EGF-stimulated increase in basal Ca efflux with no concomitant oscillations. Future work will attempt to locate the site of the dominant oscillator, to combine the self-referencing Ca probe with fura-2 intracellular Ca ion measurement in the same cell mass, and to extend our observations to embryos in the 1, 2, 4 and 8-cell stages.

我们这次访问的目的是检查表皮生长的作用 因子 (EGF) 激活 EGF 受体 (EGFR) 刺激 Ca 小鼠卵母细胞和胚胎中的离子通量。 我们知道EGFR是 在卵母细胞及其伴随的卵丘细胞中表达 阶段依赖的方式。 同样，EGFR 也表达于 胚胎。 EGF已被证明是促进细胞生长的重要因素 卵母细胞和胚胎的体外发育。 此外，EGFR 已知在组织培养细胞中可激活 Ca 的释放 通过磷脂酶 C 依赖性途径进行细胞内储存。 我们的 特别关注的是这种 EGFR 介导的 Ca 之间的假定耦合 Ca 的释放和潜在的刺激流出。 初步数据表明，在所有卵丘-卵母细胞复合体中 (COC) 测试 (N=3)，发现了强烈的 EGF 刺激的 Ca 流出。 令人惊讶的是，我们发现 Ca 流出的振荡周期为 在 COC 中观察到 2-4 分钟，表明主导频率 发生器调节这些间隙结耦合中的这些振荡 细胞复合物。 值得注意的是，卵丘无细胞卵母细胞仅显示 EGF 刺激基础 Ca 流出增加，但不伴随 振荡。 未来的工作将尝试找到该网站的位置 主振荡器，将自参考 Ca 探头与 在同一细胞团中进行fura-2细胞内Ca离子测量，并 将我们的观察扩展到 1、2、4 和 8 细胞阶段的胚胎。