营养素调节Tor1的核定位和与rDNA促进体的关联
Hong Li1, Chi Kwan Tsang, Marcus Watkins
1Department of Pharmacology, Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, New Jersey 08854, USA.
Nature
|August 11, 2006
概括
拉帕素 (TOR) 途径的标调节细胞生长. 在酵母中,Tor1核定位对于35SrRNA合成和细胞生长至关重要,证明了TOR复合体1的存在.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 拉帕素 (TOR) 途径的目标是细胞生长的中心调节者,影响细胞质和核过程.
- 了解TOR信号的空间和时间调节,特别是核转移,至关重要,但仍然有限.
研究的目的:
- 为了研究Tor1在酵母细胞内的动态定位.
- 确定Tor1核定位在调节基因表达和细胞过程中的作用.
- 阐明TOR信号影响35SrRNA合成和细胞生长的机制.
主要方法:
- 显微镜观察酵母细胞质和核中的动态Tor1分布.
- 营养物质操纵和拉巴胺治疗以评估Tor1局部化的变化.
- 对基因表达 (氨基酸载体,核糖体蛋白质) 和35SrRNA合成的分析.
- 对Tor1与35S核糖体DNA (rDNA) 促进体的染色体关联研究.
主要成果:
- 在酵母中,Tor1表现出动态的细胞质和核定位,这取决于营养素的可用性和拉巴amycin.
- 在饥饿或拉巴胺治疗后,Tor1会离开细胞核.
- 核Tor1对于35SrRNA合成和细胞生长至关重要,但对于氨基酸载体或核糖体蛋白质基因表达并非如此.
- 托尔1与35SrDNA促销器染色质以一种对拉巴胺素和饥饿敏感的方式结合在一起.
结论:
- 通过核定位对TOR复合体1 (TORC1) 的空间调节对于特定的基因调节至关重要,特别是35S rRNA合成.
- 比以前理解的,TOR信号更密切地参与基因调节,超出了细胞质激酶活性.
- 托尔1的动态核-细胞质穿提供了一种机制,以营养依赖控制重要的细胞过程,如核糖体生物发生.
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