一个由TERT和RMRPRNA组成的RNA依赖RNA聚合酶
Yoshiko Maida1, Mami Yasukawa, Miho Furuuchi
1Cancer Stem Cell Project, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
Nature
|August 25, 2009
概括
人类端粒酶 (TERT) 与线粒体RNA处理 (RMRP) 相互作用,形成一种新的RNA依赖RNA聚合酶. 这种复合物产生双链RNA被加工成小干扰RNA,揭示了TERT在端粒维护之外的新作用.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 构造性端粒酶表达通过保持端粒长度来防止细胞衰老.
- 新出现的证据表明,人体端粒酶逆转录酶催化子单元 (TERT) 具有超出端粒延长的功能.
- 线粒体RNA处理核糖核酶 (RMRP) 中的突变会导致软骨-毛发缺血症,这是一种类型综合征.
研究的目的:
- 研究人类TERT的非端粒功能.
- 确定TERT的新型交互伙伴和生物化学活动.
- 阐明TERT外分子作用背后的分子机制.
主要方法:
- 同免疫沉测试以确定TERT相互作用伙伴.
- 生物化学测试以表征TERT-RMRP复合物的酶活性.
- RNA干扰和Dicer淘汰实验,以评估小RNA的产生.
主要成果:
- 人类TERT直接与RMRP的RNA成分相互作用.
- TERT和RMRP形成了一个独特的核糖核蛋白复合体,具有RNA依赖RNA聚合酶 (RdRP) 活性.
- 这种复合物产生双链RNA,这些RNA被Dicer处理成小干扰RNA.
结论:
- 一种新的哺乳动物RNA依赖RNA聚合酶已被确定,由TERT和RMRP组成.
- TERT具有以前未知的酶功能,独立于端粒维护.
- 这一发现为了解TERT在细胞生理学和疾病中的作用开辟了新的途径.
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