Multiple RPAs make WRN syndrome protein a superhelicase

Mina Lee; Soochul Shin; Heesoo Uhm; Heesun Hong; Jaewon Kirk; Kwangbeom Hyun; Tomasz Kulikowicz; Jaehoon Kim; Byungchan Ahn; Vilhelm A Bohr; Sungchul Hohng

doi:10.1093/nar/gky272

Multiple RPAs make WRN syndrome protein a superhelicase

Nucleic Acids Res. 2018 May 18;46(9):4689-4698. doi: 10.1093/nar/gky272.

Authors

Affiliations

¹ Center for Nano-Bio Measurement, Korea Research Institute of Standards and Science, Daejeon, Republic of Korea.
² Department of Physics and Astronomy, Institute of Applied Physics, National Center of Creative Research Initiatives, Seoul National University, Seoul, Republic of Korea.
³ Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea.
⁴ Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
⁵ Department of Life Sciences, University of Ulsan, Ulsan, Republic of Korea.

Abstract

RPA is known to stimulate the helicase activity of Werner syndrome protein (WRN), but the exact stimulation mechanism is not understood. We use single-molecule FRET and magnetic tweezers to investigate the helicase activity of WRN and its stimulation by RPA. We show that WRN alone is a weak helicase which repetitively unwind just a few tens of base pairs, but that binding of multiple RPAs to the enzyme converts WRN into a superhelicase that unidirectionally unwinds double-stranded DNA more than 1 kb. Our study provides a good case in which the activity and biological functions of the enzyme may be fundamentally altered by the binding of cofactors.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Fluorescence Resonance Energy Transfer
Humans
Replication Protein A / metabolism*
Werner Syndrome Helicase / metabolism*

Substances

Replication Protein A
WRN protein, human
Werner Syndrome Helicase