TERRA R环连接并保护在线粒分裂中的姐妹端粒
Samantha Sze1, Amit Bhardwaj2, Priyanka Fnu3
1Department of Cell Biology, New York University School of Medicine, New York, NY 10016, USA.
Cell reports
|October 16, 2023
概括
在老年人细胞中,端粒重复含有RNA (TERRA) 形成RNA-DNA杂交体,将姐妹端粒保持在一起. 这种持久的凝聚力由C19orf43调节,延迟细胞衰老.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 姐妹端粒凝聚力解决对于线粒分裂至关重要,并取决于TRF1-tankyrase的招募.
- 在老年人体细胞中,缩短的端粒表现出不足的TRF1/tankyrase招募,导致持续的姐妹端粒凝聚力.
- 维持老化细胞中这种持久凝聚力的确切机制尚不清楚.
研究的目的:
- 阐明姐妹端粒在老年人体细胞中保持连贯的机制.
- 研究端粒重复含有RNA (TERRA) 和相关蛋白质在端粒凝聚中的作用.
- 了解这个过程如何影响细胞衰老.
主要方法:
- 研究了RNA结合蛋白C19orf43在TERRA R循环调节中的作用.
- 利用RNaseH1治疗来确认RNA-DNA杂交体在姐妹端粒凝聚中的作用.
- 在改变C19orf43水平的细胞中评估了DNA损伤和复制性衰老.
主要成果:
- 泰拉形成RNA-DNA杂交体 (R环),在物理上将姐妹端粒保持在一起.
- 与坦基拉酶相互作用的蛋白C19orf43对于抑制TERRA R-循环至关重要.
- 衰老细胞中C19orf43的耗尽导致持续的端粒凝聚力,而RNaseH1.1则会逆转这种凝聚力.
- 衰老细胞中C19orf43的枯竭减少了DNA损伤,并延迟了衰老.
结论:
- 由TERRA介导的R环是维持老细胞中持续的姐妹端粒凝聚力的关键机制.
- C19orf43作为这些促进凝聚力的R循环的抑制剂.
- 缩短的端粒无法招募R循环抑制机器,这有助于控制衰老的开始.
关键词:
在C19orf43中使用.科普:分子生物学 分子生物学在R-Loops中使用R-Loops.这是RNA-DNA混合体.在RNaseH中使用.在地球上,地球是地球.TRF1 转换法1 转换法1 转换法凝聚力 凝聚力 凝聚力衰老是一种老化.坦基拉斯 (tankyrase) 是一个水箱.端粒是什么意思 端粒是什么意思更多相关视频
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