MALAT1 RNA成熟和mascRNA生物发生的结构基础
Ilias Skeparnias1, Charles Bou-Nader1, Dimitrios G Anastasakis2
1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, USA.
Nature structural & molecular biology
|July 2, 2024
概括
转移相关的肺腺癌转录1 (MALAT1) 长非编码RNA (lncRNA) 使用独特的准转移RNA (tRNA) 结构进行处理. 这种精简的架构为RNA成熟招募特定的酶,而不会干扰翻译.
科学领域:
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
- 结构生物学 结构生物学
背景情况:
- 转移相关的肺腺癌转录1 (MALAT1) 是一个长非编码RNA (lncRNA),对基因调节和瘤发生至关重要.
- 马拉特1的成熟涉及RNase P的处理,产生3'细胞质MALAT1相关的小细胞质RNA (mascRNA).
- mascRNA具有拟议的tRNA类似结构,但缺乏正规的tRNA连接残留物.
研究的目的:
- 在处理前和处理后确定人类mascRNA的晶体结构.
- 通过加工酶阐明mascRNA识别的结构基础.
- 了解mascRNA的结构如何决定其功能和与细胞机械的相互作用.
主要方法:
- 进行X射线晶体学,以获得mascRNA的高分辨率结构.
- 生物化学测试以评估酶特异性和基质相互作用.
- 使用正规转移RNA (tRNA) 的比较结构分析.
主要成果:
- 晶体结构显示mascRNA采用了超紧的,类似tRNA的近似折叠.
- 尽管缺乏关键残留物,但mascRNA模仿tRNA"肘部"来招募RNase P和ELAC2.
- 结构重组阻止了mascRNA的氨基化,将其功能与翻译分开.
结论:
- 甲基动物的lncRNA可以利用精简的准tRNA架构来进行特定的RNA处理.
- 这种独特的结构可以招募精选的tRNA处理酶,同时排除其他酶.
- 这些发现揭示了由lncRNA结构驱动的定制RNA生物发生,处理和成熟的新机制.
相关概念视频
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Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a cap to the 5' end of the growing transcript. In this process, a 5' phosphate is replaced by modified guanosine that has a methyl group attached (7-methyl guanosine). This 5' cap helps...
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