RNA螺旋酶Mtr4p调节TRAMP复合体中的多基化
Huijue Jia1, Xuying Wang, Fei Liu
1Center for RNA Molecular Biology & Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
Cell
|June 14, 2011
概括
对于RNA处理和衰变至关重要的TRAMP复合体,限制了poly (A) 尾添加到3-4个腺. RNA螺旋酶Mtr4p通过感知腺数量并调整酶活性来控制这种长度限制.
科学领域:
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
- 生物化学 生物化学
背景情况:
- TRAMP复合体 (Trf4p,Air2p,Mtr4p) 对于核RNA的处理,监测和降解至关重要.
- TRAMP聚氨基化了核外体向衰变的RNA,但它的机制不同于常规的聚氨基化.
研究的目的:
- 为了阐明TRAMP多化RNA的机制.
- 了解TRAMP的多基化活性与传统的多A) 聚合酶有何不同.
- 为了确定RNA螺旋酶Mtr4p在TRAMP介导的多基解中的作用.
主要方法:
- 在体外复制Saccharomyces cerevisiae TRAMP复合物.
- 生物化学测试以测量多化活性和酶动力学.
- 分析RNA基酶Mtr4p与TRAMP的相互作用及其对多甲尾长度的影响.
主要成果:
- 复制后的TRAMP固有地抑制了超过3-4个腺的多A) 添加.
- RNA螺旋酶Mtr4p是这种多元尾长度限制的关键调节器.
- Mtr4p感知3'-终端腺的数量,并调节ATP亲和力和腺和TRAMP解离的速率常数.
结论:
- Mtr4p作为TRAMP的多基化活性的一个关键调节剂.
- RNA螺旋酶可以复杂地控制酶活性,以响应RNA特征.
- 这项研究揭示了一种用于TRAMP复合体精确调节多基解的新型机制.
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