RNA螺旋酶Dbp10在核糖体生物发生过程中协调组装因子与PTC成熟的关联
Valentin Mitterer1,2, Hussein Hamze3, Natalia Kunowska4
1Biochemistry Center, University of Heidelberg, 69120 Heidelberg, Germany.
Nucleic acids research
|December 19, 2023
概括
死亡盒RNA螺旋酶Dbp10对于核糖体生物生成至关重要. 它的催化活性重组了前核糖体RNA,使组装因子对接和核糖体子单元的适当成熟成为可能.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生化学
背景情况:
- 核糖体生物发生是一个复杂的,多步骤的过程,对于细胞活力至关重要.
- 组装因子和酶指导着核糖体子单元的成熟.
- 死亡盒RNA螺旋酶Dbp10与60S核糖体组装中间体的基转移酶中心 (PTC) 内的前核糖体RNA (rRNA) 的重组有关.
研究的目的:
- 为了研究Dbp10的酶活性在60S核糖体生物发生中的作用.
- 阐明Dbp10促进前核糖体组装的分子机制.
主要方法:
- 在Dbp10中保存的化酶核心基因的部位定向突变发生.
- 在突变菌株中分析主导致死生长表型.
- 生物化学试验以评估60S组装前的中间成熟和因子关联.
- 同免疫沉用于研究蛋白质与蛋白质相互作用.
主要成果:
- 在Dbp10的催化核心基因的点突变导致主导致命的表型.
- 突变Dbp10蛋白稳定地与60S前的中间体结合在一起,在核细胞阶段破坏生物发生.
- 在Rrp14释放和Noc3集成之前,Pre-60S成熟被阻止.
- 抑制了GTPase Nug1与突变Dbp10相关粒子的结合.
- Dbp10 促进了 Spb1 的结合和随后的 25S rRNA 在核酸 G2922.22 的甲基化.
结论:
- Dbp10的螺旋酶活性对于创建允许组装因子对接的框架至关重要.
- 这种框架对于PTCrRNA的甲基化和60S前核糖体子单元成熟的进展至关重要.
- Dbp10在核糖体组装的后期阶段起到关键调节者的作用.
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