通过细胞内胰岛素刺激RNA和蛋白质合成
1Laboratory of Cellular and Molecular Pharmacology, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709.
概括
细胞外和细胞内胰岛素刺激Xenopus laevis卵细胞的生长. 胰岛素是一种胰岛素.
科学领域:
- * 细胞生物学 细胞生物学
- * 内分泌学 在内分泌学.
- * 分子生物学 * 分子生物学
背景情况:
- *胰岛素是调节细胞代谢和各种组织生长的关键激素.
- *卵细胞,女性生殖细胞,在成熟期间经历了显著的代谢变化.
- * 胰岛素在卵细胞中的确切作用机制尚未完全理解.
研究的目的:
- * 为了研究胰岛素对Xenopus laevis第四阶段卵细胞中的宏分子合成的影响.
- * 确定胰岛素通过细胞表面受体或细胞内作用.
- * 为了在卵细胞内识别胰岛素作用的潜在细胞内部位.
主要方法:
- *Xenopus laevis在第四阶段的卵细胞在体外培养.
- *卵子暴露于细胞外胰岛素或接受微注射细胞内胰岛素.
- * 用隔离的卵细胞核来测试直接的核胰岛素效应.
- * 测量了RNA,蛋白质和糖原的合成.
主要成果:
- * 细胞外和细胞内胰岛素都增加了卵细胞中的RNA,蛋白质和糖原合成.
- * 外部和细胞内胰岛素的影响是附加的,表明不同的途径.
- * 直接将胰岛素应用于分离的细胞核刺激了RNA合成.
结论:
- *胰岛素对Xenopus卵细胞产生显著的合成作用,促进RNA,蛋白质和糖原的合成.
- * 单独的机制调解细胞外和细胞内胰岛素的作用.
- * 卵细胞核被确定为胰岛素激素作用的部位.
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