中国物理B ›› 2017, Vol. 26 ›› Issue (8): 88701-088701.doi: 10.1088/1674-1056/26/8/088701
• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇 下一篇
Zhen-Ye Zhao(赵振业), Chun-Hua Xu(徐春华), Jing Shi(史婧), Jing-Hua Li(李菁华), Jian-Bing Ma(马建兵), Qi Jia(贾棋), Dong-Fei Ma(马东飞), Ming Li(李明), Ying Lu(陆颖)
Zhen-Ye Zhao(赵振业)1,2, Chun-Hua Xu(徐春华)1,2, Jing Shi(史婧)3, Jing-Hua Li(李菁华)4, Jian-Bing Ma(马建兵)1,2, Qi Jia(贾棋)1,2, Dong-Fei Ma(马东飞)1,2, Ming Li(李明)1,2, Ying Lu(陆颖)1,2
摘要:
The Bloom helicase (BLM) gene product encodes a DNA helicase that functions in homologous recombination repair to prevent genomic instability. BLM is highly active in binding and unfolding G-quadruplexes (G4), which are non-canonical DNA structures formed by Hoogsteen base-pairing in guanine-rich sequences. Here we use single-molecule fluorescence resonance energy transfer (smFRET) to study the molecular mechanism of BLM-catalysed G4 unfolding and show that BLM unfolds G4 in two pathways. Our data enable us to propose a model in which the HRDC domain functions as a regulator of BLM, depending on the position of the HRDC domain of BLM in action: when HRDC binds to the G4 sequence, BLM may hold G4 in the unfolded state; otherwise, it may remain on the unfolded G4 transiently so that G4 can refold immediately.
中图分类号: (Nucleic acids)