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Helicase Unwinding at the Replication Fork

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Molecular Biophysics for the Life Sciences

Part of the book series: Biophysics for the Life Sciences ((BIOPHYS,volume 6))

Abstract

Ring-shaped hexameric helicases play an essential role of double-stranded DNA unwinding during genome replication. The NTPase-powered unwinding activity of the hexameric helicases is required both for replication initiation and fork progression. We describe ensemble biophysical methods to measure the unwinding activity of ring-shaped helicases during fork progression using the T7 bacteriophage replicative helicase gp4A′ as a model enzyme. These assays provide insights into the stepping mechanism of translocation, active or passive mechanism of unwinding, and regulation by associated proteins such as single strand DNA binding protein, DNA polymerase, and primase enzymes.

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Acknowledgements

We thank former and current Patel Lab members for developing and testing the methods and models described in this review. This work was supported by National Institute of Health (NIH) grant GM55310.

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Authors and Affiliations

  1. Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, 675 Hoes lane, Piscataway, NJ, 08854, USA

    Divya Nandakumar & Smita S. Patel

Authors
  1. Divya Nandakumar
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  2. Smita S. Patel
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Correspondence to Smita S. Patel .

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Editors and Affiliations

  1. Chemistry and Biochemistry, University of Maryland, College Park, Maryland, USA

    Norma Allewell

  2. Research & Development, Amgen, Inc., Thousand Oaks, California, USA

    Linda O. Narhi

  3. Department of Biochemistry, University of Wisconsin - Madison, Madison, Wisconsin, USA

    Ivan Rayment

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Nandakumar, D., Patel, S.S. (2013). Helicase Unwinding at the Replication Fork. In: Allewell, N., Narhi, L., Rayment, I. (eds) Molecular Biophysics for the Life Sciences. Biophysics for the Life Sciences, vol 6. Springer, New York, NY. https://doi.org/10.1007/978-1-4614-8548-3_9

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