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
In Press
Peer-reviewed
Oui
Language
english
Notes
Publication types: Journal Article
Publication Status: aheadofprint
Publication Status: aheadofprint
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.
Pubmed
Open Access
Yes
Create date
28/10/2024 14:18
Last modification date
29/10/2024 7:22