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

Bloom's syndrome protein unfolding G-quadruplexes in two pathways

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)   

  1. 1 Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    2 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics and School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China;
    3 College of Life Science, Northwest A & F University, Xianyang 712100, China;
    4 Material and Energy School, Guangdong University of Technology, Guangzhou 510006, China
  • 收稿日期:2017-03-24 修回日期:2017-04-12 出版日期:2017-08-05 发布日期:2017-08-05
  • 通讯作者: Ying Lu E-mail:yinglu@iphy.ac.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11674382, 11574381, and 11574382) and the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (Grant No. QYZDJ-SSW-SYS014).

Bloom's syndrome protein unfolding G-quadruplexes in two pathways

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   

  1. 1 Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    2 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics and School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China;
    3 College of Life Science, Northwest A & F University, Xianyang 712100, China;
    4 Material and Energy School, Guangdong University of Technology, Guangzhou 510006, China
  • Received:2017-03-24 Revised:2017-04-12 Online:2017-08-05 Published:2017-08-05
  • Contact: Ying Lu E-mail:yinglu@iphy.ac.cn
  • About author:0.1088/1674-1056/26/8/
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11674382, 11574381, and 11574382) and the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (Grant No. QYZDJ-SSW-SYS014).

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.

关键词: G-quadruplexes, BLM, helicase, smFRET

Abstract:

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.

Key words: G-quadruplexes, BLM, helicase, smFRET

中图分类号:  (Nucleic acids)

  • 87.14.G-
87.15.H- (Dynamics of biomolecules) 87.15.kj (Protein-polynucleotide interactions)