在Xenopus mesoderm诱导过程中p21ras的参与
1Department of Biochemistry and Molecular Biology, Cambridge, Massachusetts.
Nature
|May 21, 1992
概括
在脊椎动物早期发育过程中,ras蛋白对中皮层诱导至关重要. 抑制Ras阻断了来自纤维细胞生长因子和活性素的信号,突出了它在胚胎发生中的核心作用.
科学领域:
- 发展生物学 发展生物学
- 细胞信号传递 细胞信号传递
- 分子胚胎学 分子胚胎学
背景情况:
- 在早期脊椎动物胚胎发生过程中,中皮层的特异性是由来自潜在内皮层的信号触发的.
- 纤维细胞生长因子 (FGF) 和转化生长因子-β (TGF-β) 家族可以模仿这种介质皮诱导信号.
- p21c-ras原型瘤基因产物参与各种生长因子的信号转导.
研究的目的:
- 调查p21ras在Xenopus中中皮质诱导信号转导途径中的作用.
- 确定p21ras是否是介导内源和外源中体诱导信号的核心组成部分.
主要方法:
- 利用Xenopus蛋的信使RNA微注射来表达一种主要的抑制性ras突变 (p21(Asn17) Ha-ras).
- 评估了主导抑制性ras突变物对纤维细胞生长因子,活性素和内源性内皮信号的中皮诱导的影响.
- 检查了一个构成性活跃的ras突变体对中皮诱导的影响.
主要成果:
- 一种主要的抑制性ras突变物有效地阻断了纤维细胞生长因子,活性素和内源信号的中皮诱导.
- 一个构成性活跃的ras突变分子部分模仿了介质皮诱导活动.
- 这些发现强烈地涉及p21ras在介质体诱导信号的转导.
结论:
- 在脊椎动物胚胎发生过程中,p21ras在介质体诱导的信号转导途径中发挥着中心作用.
- 纤维细胞生长因子和活性素是内源性中皮层诱导分子的关键候选者,利用p21ras依赖的途径.
- 了解p21ras信号对于破译早期胚胎发育的分子机制至关重要.
相关概念视频
The Ras Gene
The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a superfamily...
Ras is a superfamily...
Small GTPases - Ras and Rho
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity:
MAPK Signaling Cascades
Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...


