Mechanisms of HCV NS3 Helicase Monitored by Optical Tweezers

  • Wei ChengEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1259)


As one of the essential enzymes for viral genome replication, the hepatitis C virus NS3 helicase is one of the best characterized RNA helicases to date in understanding the mechanistic cycles in a helicase-catalyzed strand separation reaction. Recently, single-molecule studies on NS3, in particular the use of optical tweezers with sub-base pair spatial resolution, have allowed people to examine the potential elementary steps of NS3 in unwinding the double-stranded RNA fueled by ATP binding and hydrolysis. In this chapter, I detail the essential technical elements involved in conducting a high-resolution optical tweezers study of NS3 helicase, starting from the purification of the recombinant helicase protein from E. coli to setting up a high-resolution single-molecule experiment using optical tweezers.

Key words

RNA helicase Optical tweezers Hepatitis C virus NS3 Single-molecule 



This work was supported by NSF CAREER Award CHE1149670 to WC, NIH Director’s New Innovator Award 1DP2OD008693 to WC, and also in part by Research Grant No. 5-FY10-490 to WC from the March of Dimes Foundation.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Department of Pharmaceutical SciencesUniversity of MichiganAnn ArborUSA
  2. 2.Department of BiophysicsUniversity of MichiganAnn ArborUSA

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