Direct observation of RuvAB-catalyzed branch migration of single Holliday junctions.

Holliday junctions form during DNA repair and homologous recombination processes. These processes entail branch migration, whereby the length of two arms of a cruciform increases at the expense of the two others. Branch migration is carried out in prokaryotic cells by the RuvAB motor complex. We stu...

Full description

Bibliographic Details
Main Authors: Amit, R, Gileadi, O, Stavans, J
Format: Journal article
Language:English
Published: 2004
_version_ 1826299857887821824
author Amit, R
Gileadi, O
Stavans, J
author_facet Amit, R
Gileadi, O
Stavans, J
author_sort Amit, R
collection OXFORD
description Holliday junctions form during DNA repair and homologous recombination processes. These processes entail branch migration, whereby the length of two arms of a cruciform increases at the expense of the two others. Branch migration is carried out in prokaryotic cells by the RuvAB motor complex. We study RuvAB-catalyzed branch migration by following the motion of a small paramagnetic bead tethered to a surface by two opposing arms of a single cruciform. The bead, pulled under the action of magnetic tweezers, exerts tension on the cruciform, which in turn transmits the force to a single RuvAB complex bound at the crossover point. This setup provides a unique means of measuring several kinetic parameters of interest such as the translocation rate, the processivity, and the force on the substrate against which the RuvAB complex cannot effect translocation. RuvAB-catalyzed branch migration proceeds with a small, discrete number of rates, supporting the view that the monomers comprising the RuvB hexameric rings are not functionally homogeneous and that dimers or trimers constitute the active subunits. The most frequently encountered rate, 98 +/- 3 bp/sec, is approximately five times faster than previously estimated. The apparent processivity of branch migration between pauses of inactivity is approximately 7,000 bp. Branch migration persists against opposing forces up to 23 pN.
first_indexed 2024-03-07T05:08:21Z
format Journal article
id oxford-uuid:dab0b427-6447-49a0-9024-fe52793c36ea
institution University of Oxford
language English
last_indexed 2024-03-07T05:08:21Z
publishDate 2004
record_format dspace
spelling oxford-uuid:dab0b427-6447-49a0-9024-fe52793c36ea2022-03-27T09:05:06ZDirect observation of RuvAB-catalyzed branch migration of single Holliday junctions.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:dab0b427-6447-49a0-9024-fe52793c36eaEnglishSymplectic Elements at Oxford2004Amit, RGileadi, OStavans, JHolliday junctions form during DNA repair and homologous recombination processes. These processes entail branch migration, whereby the length of two arms of a cruciform increases at the expense of the two others. Branch migration is carried out in prokaryotic cells by the RuvAB motor complex. We study RuvAB-catalyzed branch migration by following the motion of a small paramagnetic bead tethered to a surface by two opposing arms of a single cruciform. The bead, pulled under the action of magnetic tweezers, exerts tension on the cruciform, which in turn transmits the force to a single RuvAB complex bound at the crossover point. This setup provides a unique means of measuring several kinetic parameters of interest such as the translocation rate, the processivity, and the force on the substrate against which the RuvAB complex cannot effect translocation. RuvAB-catalyzed branch migration proceeds with a small, discrete number of rates, supporting the view that the monomers comprising the RuvB hexameric rings are not functionally homogeneous and that dimers or trimers constitute the active subunits. The most frequently encountered rate, 98 +/- 3 bp/sec, is approximately five times faster than previously estimated. The apparent processivity of branch migration between pauses of inactivity is approximately 7,000 bp. Branch migration persists against opposing forces up to 23 pN.
spellingShingle Amit, R
Gileadi, O
Stavans, J
Direct observation of RuvAB-catalyzed branch migration of single Holliday junctions.
title Direct observation of RuvAB-catalyzed branch migration of single Holliday junctions.
title_full Direct observation of RuvAB-catalyzed branch migration of single Holliday junctions.
title_fullStr Direct observation of RuvAB-catalyzed branch migration of single Holliday junctions.
title_full_unstemmed Direct observation of RuvAB-catalyzed branch migration of single Holliday junctions.
title_short Direct observation of RuvAB-catalyzed branch migration of single Holliday junctions.
title_sort direct observation of ruvab catalyzed branch migration of single holliday junctions
work_keys_str_mv AT amitr directobservationofruvabcatalyzedbranchmigrationofsinglehollidayjunctions
AT gileadio directobservationofruvabcatalyzedbranchmigrationofsinglehollidayjunctions
AT stavansj directobservationofruvabcatalyzedbranchmigrationofsinglehollidayjunctions