Competitive binding of MatP and topoisomerase IV to the MukB hinge domain
- London Institute of Medical Sciences, United Kingdom
- University of Oxford, United Kingdom
- Stanford University, United States
- University of Cambridge, United Kingdom
Abstract
Structural Maintenance of Chromosomes (SMC) complexes have ubiquitous roles in compacting DNA linearly, thereby promoting chromosome organization-segregation. Interaction between the Escherichia coli SMC complex, MukBEF, and matS-bound MatP in the chromosome replication termination region, ter, results in depletion of MukBEF from ter, a process essential for efficient daughter chromosome individualisation and for preferential association of MukBEF with the replication origin region. Chromosome-associated MukBEF complexes also interact with topoisomerase IV (ParC2E2), so that their chromosome distribution mirrors that of MukBEF. We demonstrate that MatP and ParC have an overlapping binding interface on the MukB hinge, leading to their mutually exclusive binding, which occurs with the same dimer to dimer stoichiometry. Furthermore, we show that matS DNA competes with the MukB hinge for MatP binding. Cells expressing MukBEF complexes that are mutated at the ParC/MatP binding interface are impaired in ParC binding and have a mild defect in MukBEF function. The data highlight competitive binding as a means of globally regulating MukBEF-topoisomerase IV activity in space and time.
Data availability
Source data files have been provided for all gel-based figures. Source data files for other assays have been included where indicated. All custom MATLAB scripts are provided as Source Code 1. All code used is previously published and also available via the cited reference(s). All reagents are available upon reasonable request.
Article and author information
Author details
Lidia K Arciszewska
Funding
Wellcome Trust (200782/Z/16/Z)
- David J Sherratt
Medical Research Council (MR/N020413/1)
- Carol V Robinson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Fisher et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Competitive binding of MatP and topoisomerase IV to the MukB hinge domain
eLife 10:e70444.
https://doi.org/10.7554/eLife.70444
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