聚氨酸中的N6甲基氨酸稳定VSG转录
Idálio J Viegas1, Juan Pereira de Macedo1, Lúcia Serra1
1Instituto de Medicina Molecular-João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.
Nature
|March 31, 2022
概括
在Trypanosoma brucei中,N6-甲基氨酸 (m6A) 基因修饰调节基因表达,特别是在变异性表面糖蛋白转录的多元A尾部内,影响mRNA的稳定性.
科学领域:
- 分子生物学
- 寄生虫学
- 核糖核酸生物学
背景情况:
- 在Trypanosoma brucei中,基因表达主要是由于其多晶体转录而通过转录后进行调节的.
- 在Trypanosoma brucei中发现了N6-甲基氨酸 (m6A),但其功能性作用尚不清楚.
研究的目的:
- 在Trypanosoma brucei中研究m6ARNA修饰的功能.
- 识别与m6A修改相关的转录和监管元素.
主要方法:
- 通过RNA免疫沉识别m6A丰富的转录物.
- 计算分析以确定与m6A相关的序列动机.
- 基因操纵以评估在m6A调控中发现的动机的作用.
主要成果:
- m6A修饰在342个转录中得到丰富,包括编码变异表面糖蛋白 (VSG) 的转录.
- 大约50%的m6A存在于VSG转录的poly(A) 尾部,在降解之前被删除.
- 在VSG基因的3'未翻译区域中的16-mer基因对m6A纳入多元A尾部至关重要.
结论:
- 这项研究确定了真核mRNA的多元A尾部内的m6A修饰,这是转录后基因调节的新机制.
- 作为一个控制m6A结合和随后的mRNA稳定性的cis-acting元素,16-mer动机在Trypanosoma brucei中起作用.
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