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Published on: June 25, 2013
Hin-mediated DNA knotting and recombining promote replicon dysfunction and mutation
Richard W Deibler1, Jennifer K Mann, De Witt L Sumners
1Interdepartmental Program in Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030-3411, USA. richard_deibler@hms.harvard.edu <richard_deibler@hms.harvard.edu>
BMC Molecular Biology
|May 29, 2007
Summary
DNA knotting and recombination can be toxic to cells. These processes block DNA replication and transcription, leading to genetic rearrangements and potentially driving evolution.
Area of Science:
- Molecular Biology
- Genetics
Background:
- Cellular DNA must balance encoding complexity with physical constraints.
- DNA's physical properties promote self-collision, knotting, and recombination.
- Physiological consequences of DNA reactivity remain largely unestablished.
Purpose of the Study:
- To investigate the physiological effects of DNA knotting and recombination in E. coli.
- To determine the impact of these DNA topological states on cellular processes.
Main Methods:
- Utilized the Hin site-specific recombination system in E. coli.
- Analyzed the effects of Hin-mediated DNA knotting and recombination on plasmids.
Main Results:
- DNA knotting and recombination promote replicon loss by inhibiting DNA replication.
- These DNA topological changes block gene transcription.
- Genetic rearrangements occur at rates 1000-10000 times higher than in unmanipulated plasmids.
Conclusions:
- DNA reactivity, leading to knots and recombination, is potentially toxic to cells.
- This DNA reactivity may serve as a mechanism driving genetic evolution.
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