中国物理B ›› 2017, Vol. 26 ›› Issue (6): 68701-068701.doi: 10.1088/1674-1056/26/6/068701

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Helicase activity and substrate specificity of RecQ5β

Jing You(尤菁), Ya-Nan Xu(徐雅楠), Hui Li(李辉), Xi-Ming Lu(吕袭明), Wei Li(李伟), Peng-Ye Wang(王鹏业), Shuo-Xing Dou(窦硕星), Xu-Guang Xi(奚绪光)   

  1. 1 Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences(CAS), Beijing 100190, China;
    2 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China;
    3 College of Life Science, Inner Mongolia University for Nationalities, Tongliao 028000, China;
    4 College of Life Sciences, Northwest Agriculture and Forestry University, Yangling 712100, China;
    5 LBPA, IDA, ENS Cachan, CNRS, Universite Paris-Saclay, Cachan F-94235, France
  • 收稿日期:2017-03-11 修回日期:2017-04-10 出版日期:2017-06-05 发布日期:2017-06-05
  • 通讯作者: Hui Li, Shuo-Xing Dou E-mail:huili@iphy.ac.cn;sxdou@iphy.ac.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11674383, 11474346, and 11274374), the National Basic Research Program of China (Grant No. 2013CB837200), and the National Key Research and Development Program of China (Grant No. 2016YFA0301500).

Helicase activity and substrate specificity of RecQ5β

Jing You(尤菁)1,2, Ya-Nan Xu(徐雅楠)3, Hui Li(李辉)1,2, Xi-Ming Lu(吕袭明)1,2, Wei Li(李伟)1,2, Peng-Ye Wang(王鹏业)1,2, Shuo-Xing Dou(窦硕星)1,2, Xu-Guang Xi(奚绪光)4,5   

  1. 1 Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences(CAS), Beijing 100190, China;
    2 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China;
    3 College of Life Science, Inner Mongolia University for Nationalities, Tongliao 028000, China;
    4 College of Life Sciences, Northwest Agriculture and Forestry University, Yangling 712100, China;
    5 LBPA, IDA, ENS Cachan, CNRS, Universite Paris-Saclay, Cachan F-94235, France
  • Received:2017-03-11 Revised:2017-04-10 Online:2017-06-05 Published:2017-06-05
  • Contact: Hui Li, Shuo-Xing Dou E-mail:huili@iphy.ac.cn;sxdou@iphy.ac.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11674383, 11474346, and 11274374), the National Basic Research Program of China (Grant No. 2013CB837200), and the National Key Research and Development Program of China (Grant No. 2016YFA0301500).

摘要:

RecQ5β is an essential DNA helicase in humans, playing important roles in DNA replication, repair, recombination and transcription. The unwinding activity and substrate specificity of RecQ5β is still elusive. Here, we used stopped-flow kinetic method to measure the unwinding and dissociation kinetics of RecQ5β with several kinds of DNA substrates, and found that RecQ5β could well unwind ss/dsDNA, forked DNA and Holiday junction, but was compromised in unwinding blunt DNA and G-quadruplex. Rec5β has the preferred unwinding specificity for certain DNA substrates containing the junction point, which may improve the binding affinity and unwinding activity of RecQ5β. Moreover, from a comparison with the truncated RecQ5β1-467, we discovered that the C-terminal domain might strongly influence the unwinding activity and binding affinity of RecQ5β. These results may shed light on the physiological functions and working mechanisms of RecQ5β helicase.

关键词: helicase, RecQ5β, DNA, substrate specificity, unwinding kinetics

Abstract:

RecQ5β is an essential DNA helicase in humans, playing important roles in DNA replication, repair, recombination and transcription. The unwinding activity and substrate specificity of RecQ5β is still elusive. Here, we used stopped-flow kinetic method to measure the unwinding and dissociation kinetics of RecQ5β with several kinds of DNA substrates, and found that RecQ5β could well unwind ss/dsDNA, forked DNA and Holiday junction, but was compromised in unwinding blunt DNA and G-quadruplex. Rec5β has the preferred unwinding specificity for certain DNA substrates containing the junction point, which may improve the binding affinity and unwinding activity of RecQ5β. Moreover, from a comparison with the truncated RecQ5β1-467, we discovered that the C-terminal domain might strongly influence the unwinding activity and binding affinity of RecQ5β. These results may shed light on the physiological functions and working mechanisms of RecQ5β helicase.

Key words: helicase, RecQ5β, DNA, substrate specificity, unwinding kinetics

中图分类号:  (Enzymes)

  • 87.14.ej
87.14.gk (DNA) 87.15.R- (Reactions and kinetics)