在细胞状态过渡过程中,UBR-5和UBE2D通过破坏多A结合蛋白PABP-2的稳定性来调节来自茎命运的及时退出
Jose Francisco Calva Moreno1, George Jose1, Yi M Weaver1
1Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390.
概括
在动物中,UBR-5 E3结合酶控制干细胞命运过渡. 它与LET-70一起工作以退出干细胞,对抗PABP-2以确保适当的细胞分化和发育.
科学领域:
- 发展生物学 发展生物学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- UBR5 E3酶与癌症和神经元完整性有关,但由于致命性,其体内功能尚不清楚.
- 了解干细胞命运退出对于发育和组织平衡至关重要.
研究的目的:
- 阐明UBR5 E3结合酶在动物发育中的体内功能.
- 确定调节干细胞命运退出和细胞分化的UBR5相互作用体.
- 调查UBR5和PABP-2在发育过渡中的对抗关系.
主要方法:
- 利用Caenorhabditis elegans作为一个模型生物来研究UBR5功能.
- 执行了UBR5物理交互器的功能屏幕.
- 研究了野生类型和突变动物的基因表达变化和蛋白质水平.
主要成果:
- 在C. elegans中失去UBR-5功能会导致同时发生干细胞和分化后代细胞的命运.
- E2联酶LET-70与UBR-5合作,促进干细胞的命运退出.
- 核聚A结合蛋白PABP-2对UBR-5和LET-70具有敌对作用,PABP-2水平降低可以挽救发育缺陷.
- UBR-5 限制了 PABP-2 蛋白质水平,扭转了 PABP-2-依赖基因表达程序.
- 在老化过程中,UBR-5突变体表现出长时间的干细胞标记体表达和扩展的运动性.
结论:
- UBR-5-LET-70复合体对抗PABP-2,以调节干细胞命运退出和细胞分化.
- 这种调节开关独立于诸如lin-28.8之类的多能性因子.
- UBR-5在发育过渡,蛋白质稳定和衰老中起着至关重要的作用.
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