Single molecule studies of helicases with magnetic tweezers

Samar Hodeib; Saurabh Raj; M Manosas; Weiting Zhang; Debjani Bagchi; Bertrand Ducos; Jean-François Allemand; David Bensimon; Vincent Croquette

doi:10.1016/j.ymeth.2016.06.019

Single molecule studies of helicases with magnetic tweezers

Methods. 2016 Aug 1:105:3-15. doi: 10.1016/j.ymeth.2016.06.019. Epub 2016 Jun 29.

Authors

Samar Hodeib¹, Saurabh Raj¹, M Manosas², Weiting Zhang¹, Debjani Bagchi¹, Bertrand Ducos¹, Jean-François Allemand¹, David Bensimon³, Vincent Croquette⁴

Affiliations

¹ Laboratoire de Physique Statistique, École Normale Supérieure, PSL Research University, Université Paris Diderot Sorbonne Paris-Cité, Sorbonne Universités UPMC Univ Paris 06, CNRS, 24 rue Lhomond, 75005 Paris, France; Institut de Biologie de l'Ecole Normale Supérieure, PSL Research University, F-75005 Paris, France.
² Departament de Física Fonamental, Facultat de Física, Universitat de Barcelona, 08028 Barcelona, Spain; CIBER-BBN de Bioingenieria, Biomateriales y Nanomedicina, Instituto de Sanidad Carlos III, Madrid, Spain.
³ Laboratoire de Physique Statistique, École Normale Supérieure, PSL Research University, Université Paris Diderot Sorbonne Paris-Cité, Sorbonne Universités UPMC Univ Paris 06, CNRS, 24 rue Lhomond, 75005 Paris, France; Institut de Biologie de l'Ecole Normale Supérieure, PSL Research University, F-75005 Paris, France; Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA 90095, USA.
⁴ Laboratoire de Physique Statistique, École Normale Supérieure, PSL Research University, Université Paris Diderot Sorbonne Paris-Cité, Sorbonne Universités UPMC Univ Paris 06, CNRS, 24 rue Lhomond, 75005 Paris, France; Institut de Biologie de l'Ecole Normale Supérieure, PSL Research University, F-75005 Paris, France. Electronic address: Vincent.Croquette@lps.ens.fr.

PMID: 27371121
DOI: 10.1016/j.ymeth.2016.06.019

Abstract

Helicases are a broad family of enzymes that perform crucial functions in DNA replication and in the maintenance of DNA and RNA integrity. A detailed mechanical study of helicases on DNA and RNA is possible using single molecule manipulation methods. Among those, magnetic tweezers (or traps) present a convenient, moderate throughput assay (tens of enzymes can be monitored simultaneously) that allow for high resolution (single base-pair) studies of these enzymes in various conditions and on various substrates (double and single stranded DNA and RNA). Here we discuss various implementation of the basic assay relevant for these studies.

Keywords: DNA unwinding; Fork regression; Helicases; Holliday junction migration; Magnetic traps; ds-DNA fork.

Publication types

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

MeSH terms

DNA / chemistry
DNA / genetics
DNA Helicases / chemistry*
DNA Helicases / genetics
DNA Replication / genetics
DNA, Cruciform / chemistry*
DNA, Cruciform / genetics
Magnetics / methods*
Optical Tweezers*
RNA / chemistry
RNA / genetics
Single Molecule Imaging / methods

Substances

DNA, Cruciform
RNA
DNA
DNA Helicases