DNA supercoiling enhances DNA condensation by ParB proteins.
Details
Serval ID
serval:BIB_9F0306AB2E80
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
DNA supercoiling enhances DNA condensation by ParB proteins.
Journal
Nucleic acids research
ISSN
1362-4962 (Electronic)
ISSN-L
0305-1048
Publication state
Published
Issued date
27/11/2024
Peer-reviewed
Oui
Volume
52
Number
21
Pages
13255-13268
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Publication Status: ppublish
Abstract
The ParABS system plays a critical role in bacterial chromosome segregation. The key component of this system, ParB, loads and spreads along DNA to form a local protein-DNA condensate known as a partition complex. As bacterial chromosomes are heavily supercoiled due to the continuous action of RNA polymerases, topoisomerases and nucleoid-associated proteins, it is important to study the impact of DNA supercoiling on the ParB-DNA partition complex formation. Here, we use an in-vitro single-molecule assay to visualize ParB on supercoiled DNA. Unlike most DNA-binding proteins, individual ParB proteins are found to not pin plectonemes on supercoiled DNA, but freely diffuse along supercoiled DNA. We find that DNA supercoiling enhances ParB-DNA condensation, which initiates at lower ParB concentrations than on DNA that is torsionally relaxed. ParB proteins induce a DNA-protein condensate that strikingly absorbs all supercoiling writhe. Our findings provide mechanistic insights that have important implications for our understanding of bacterial chromosome organization and segregation.
Keywords
DNA, Superhelical/metabolism, DNA, Superhelical/chemistry, DNA, Bacterial/metabolism, Bacterial Proteins/metabolism, Bacterial Proteins/chemistry, DNA-Binding Proteins/metabolism, Chromosomes, Bacterial/metabolism, Chromosomes, Bacterial/chemistry, Escherichia coli/genetics, Escherichia coli/metabolism, Single Molecule Imaging, Escherichia coli Proteins/metabolism, Chromosome Segregation
Pubmed
Web of science
Open Access
Yes
Create date
28/10/2024 14:18
Last modification date
03/12/2024 7:07