三子体线粒体3'终端尿基转移酶 (TUTase):U插入/删除RNA编辑中的关键酶
Ruslan Aphasizhev1, Sandro Sbicego, Marian Peris
1Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Cell
|March 15, 2002
概括
研究人员从Leishmania线粒体中净化了3'终端RNA尿基转移酶 (TUTase),并克隆了其基因. 这种酶对于Trypanosoma brucei中的RNA编辑至关重要,当其表达被抑制时,会影响寄生虫的生存能力.
科学领域:
- 分子生物学分子生物学
- 寄生虫学的寄生虫学
- 生物化学 生物化学
背景情况:
- RNA编辑是kinetoplastids中一个关键的转录后过程.
- 3'终端RNA尿基转移酶 (TUTases) 通过添加尿素来引导RNA,在RNA编辑中发挥关键作用.
- 了解图塔酶的功能对于理解这些生物体中的RNA代谢至关重要.
研究的目的:
- 为了净化和表征来自Leishmania tarentolae的3'终端RNA尿基转移酶 (TUTase).
- 克隆和表达来自Leishmania tarentolae和Trypanosoma brucei的TUTase基因.
- 为了研究TUTase在Trypanosoma brucei中的体内功能和相互作用.
主要方法:
- 来自Leishmania tarentolae线粒体的酶净化.
- 在 prokaryotic 系统中基因克隆和表达.
- 在Trypanosoma brucei中使用RNA干扰 (RNAi) 的体内研究.
- 使用抗-TUTase抗血清进行共同沉测定.
主要成果:
- 纯化和特征化了A Mg(2+) 依存的3'U添加特异性TUTase.
- 该酶在体内以大约500kDa的寡合体和大约700kDa的复合体形式存在.
- 发现图塔酶与RNA连接酶和指导RNA相互作用.
- 通过RNAi抑制TUTase表达导致RNA编辑的下调,并影响了寄生虫的生存能力.
结论:
- 纯化的TUTase在酶上具有活性,并且对3'U添加具有特异性.
- 图塔酶在体内以多种复杂的形式起作用,与其他关键的RNA处理因子相互作用.
- 图塔酶对于RNA编辑和Trypanosoma brucei中的寄生虫生存至关重要,突出了其作为治疗点的潜力.
相关概念视频
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One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
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