核糖体和两个S. pombe tRNA修饰突变体之间的连接受到快速tRNA衰变的影响
Thareendra De Zoysa1, Alayna C Hauke1, Nivedita R Iyer1
1Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester School of Medicine, Rochester, New York, United States of America.
PLoS genetics
|January 31, 2024
概括
核糖体蛋白质的突变通过降低核糖体水平来抑制缺乏tRNA修饰的酵母体的温度敏感性,从而影响tRNA衰变和翻译. 这表明一种保存的真核生物机制来维持细胞功能.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 酵母生物学的酵母生物学
背景情况:
- 转移RNA (tRNA) 修改对于tRNA折叠,稳定性和精确的蛋白质合成至关重要.
- 在酵母中缺乏特定tRNA修改的突变体由于低基调tRNA的快速tRNA衰变 (RTD) 而表现出温度敏感性.
研究的目的:
- 为了研究核糖体蛋白基因突变抑制酵母突变菌具有缺陷tRNA修饰的温度灵敏性的机制.
- 探索核糖体蛋白突变,tRNA水平和一般氨基酸控制 (GAAC) 途径之间的关系.
主要方法:
- 对缺乏tRNA修饰的Saccharomyces pombe突变体 (trm8Δ和tan1Δ) 的遗传分析.
- 在核糖体蛋白基因 (rpl和rps) 中抑制基因突变的识别和表征.
- 在野生型和突变菌株中评估tRNA水平,温度敏感性和GAAC通路激活.
主要成果:
- 核糖体蛋白基因 (rpl,rps) 的突变抑制了S. pombe trm8Δ和tan1Δ突变的温度敏感性.
- 抑制发生在tRNA水平的最小恢复和减少GAAC通路激活的情况下.
- 这些发现与Saccharomyces cerevisiae trm8Δ trm4Δ突变的结果是一致的,这表明一种保存机制.
结论:
- 核糖体蛋白质突变可以通过降低核糖体度来抑制tRNA修饰缺陷,从而导致核糖体碰撞和tRNA需求的减少.
- 这种抑制模型被建议在真核生物中保存,为tRNA恒常性和转化忠实性提供了洞察力.
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