编辑的mRNA的翻译用于试体线粒体中的细胞染色体b
A Horváth1, E A Berry, D A Maslov
1Department of Biology, University of California, Riverside, CA 92521, USA.
Science (New York, N.Y.)
|March 4, 2000
概括
研究人员发现了第一个直接证据,证明了蛋白质翻译在kinetoplasts. 试管体中的这种RNA编辑过程从有缺陷的前体中创建功能性信使RNA (mRNA),使蛋白质在动态细胞内合成.
科学领域:
- 分子生物学分子生物学
- 寄生虫学的寄生虫学
- 遗传学 是一个遗传学.
背景情况:
- 类细胞的基因质细胞-线粒体利用RNA编辑,包括尿酸插入/删除,以纠正前信使RNA (前mRNA) 的缺陷.
- 这一过程从非功能前体中产生可翻译的信使RNA (mRNA).
- 尽管创造了可翻译的mRNA,但几十年来,对其在动态细胞内翻译的直接证据一直缺乏.
研究的目的:
- 提供第一个直接证据,证明在试生体的动态细胞内存在一种功能转化系统.
- 为了识别特定的kinetoplast编码的蛋白质及其相应的mRNA,经过编辑和翻译.
主要方法:
- 鉴定一种基因托普拉斯特编码的阿波基因染色体b蛋白.
- 对阿波细胞染色体b的信使RNA (mRNA) 的分析,专注于5'编辑区域.
- 氨基末端蛋白的测序与编辑的mRNA中预测的序列进行比较.
主要成果:
- 鉴定出了一种kinetoplast编码的蛋白质,即apocytochrome b.
- 发现阿波细胞染色体b的mRNA在其5'区域被编辑.
- 实验确定的氨基终端蛋白质序列与从编辑的mRNA中获得的预测序列精确匹配,证实了翻译.
结论:
- 这项研究提供了第一个直接证据,即信使RNAs (mRNAs) 在动态细胞体内被功能性翻译.
- 这些发现表明,动态质体具有完整且功能性的翻译系统.
- 基内托塑体中的RNA编辑过程对于产生功能性蛋白质至关重要,例如阿波细胞染色体b.
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