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

Q Rev Biophys. 2010 May;43(2):185-217. doi: 10.1017/S0033583510000107. Epub 2010 Aug 4.


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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • DNA Helicases / chemistry
  • DNA Helicases / metabolism*
  • Enzyme Assays / methods*
  • Humans
  • Protein Conformation
  • Protein Transport
  • RNA Helicases / chemistry
  • RNA Helicases / metabolism*


  • DNA Helicases
  • RNA Helicases