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QKI将内部的m7转录转化为压力颗粒并调节mRNA代谢
Zhicong Zhao1, Ying Qing2, Lei Dong2
1Department of Systems Biology, Beckman Research Institute of City of Hope, Monrovia, CA 91016, USA; Department of Liver Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
Cell
|June 28, 2023
概括
震动蛋白 (QKI) 将内部的N7-甲基瓜诺辛 (m7G) 修饰物与信使RNA (mRNA) 结合起来. 这种相互作用调节mRNA的稳定性和翻译,影响癌细胞的化疗敏感性.
科学领域:
- 分子生物学
- RNA 修改
- 癌症研究
背景情况:
- 对于mRNA处理和蛋白质合成至关重要的是N7-甲基氨酸 (m7G) 的修饰,主要是在5'顶部.
- 在信使RNAs (mRNAs) 中的内部m7G修饰的功能意义仍然在很大程度上未被探索.
研究的目的:
- 研究内部m7G修饰在mRNA代谢中的作用.
- 识别识别和结合内部m7G修饰的mRNA的蛋白质.
- 阐明这种相互作用在细胞应激反应和药物耐药性的作用.
主要方法:
- 内部m7G甲基组的全转录组概况和映射.
- 在m7G修饰的mRNA上识别和描述Quaking蛋白 (QKI) 的结合点.
- 共同免疫沉试验用于研究蛋白质与蛋白质的相互作用 (QKI7和G3BP1).
- 在压力条件下分析mRNA稳定性和翻译效率.
主要成果:
- 鉴定出超过1,000个具有高可信度的内部m7G修饰和QKI结合的mRNA标,具有保留的"GANGAN"动机.
- 震动蛋白 (QKI) 选择性地识别和结合内部m7G修饰的mRNA.
- QKI7与压力颗粒核心蛋白G3BP1相互作用,并促进m7G修饰的转录物转移为压力颗粒.
- 这一过程调节了mRNA的稳定性和翻译,特别是减弱了Hippo信号通路基因的翻译,从而使癌细胞对化疗敏感.
结论:
- QKI作为mRNA上的内部m7G修饰的读取器.
- 内部m7G修饰和QKI结合在mRNA代谢和细胞应激反应中起着重要作用.
- QKI-QKI7-G3BP1轴调节mRNA的翻译和稳定性,影响癌细胞的耐药性和敏感性.
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