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Insight into helicase mechanism and function revealed through single-molecule approaches

Published online by Cambridge University Press:  04 August 2010

Jaya G. Yodh ,
Michael Schlierf  and
Taekjip Ha
Jaya G. Yodh
Affiliation:
Department of Physics and Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, IL, USA
Michael Schlierf
Affiliation:
Department of Physics and Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, IL, USA
Taekjip Ha*
Affiliation:
Department of Physics and Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, IL, USA Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, Urbana, IL, 61801USA
*
*Author for Correspondence: Dr. T. Ha, Department of Physics and Center for the Physics of Living Cells University of Illinois at Urbana-Champaign, 1110 West Green St., Urbana, IL 61801, USA. Tel.: 217-244-0717; Fax: 217-244-7187; Email: tjha@illinois.edu
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Abstract

Helicases are a class of nucleic acid (NA) motors that catalyze NTP-dependent unwinding of NA duplexes into single strands, a reaction essential to all areas of NA metabolism. In the last decade, single-molecule (sm) technology has proven to be highly useful in revealing mechanistic insight into helicase activity that is not always detectable via ensemble assays. A combination of methods based on fluorescence, optical and magnetic tweezers, and flow-induced DNA stretching has enabled the study of helicase conformational dynamics, force generation, step size, pausing, reversal and repetitive behaviors during translocation and unwinding by helicases working alone and as part of multiprotein complexes. The contributions of these sm investigations to our understanding of helicase mechanism and function will be discussed.

Type
Review Article
Information
Quarterly Reviews of Biophysics , Volume 43 , Issue 2 , May 2010 , pp. 185 - 217
Copyright
Copyright © Cambridge University Press 2010

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