DNA methylation by CcrM contributes to genome maintenance in the Agrobacterium tumefaciens plant pathogen.
Details
Serval ID
serval:BIB_0C3DF5C03B52
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
DNA methylation by CcrM contributes to genome maintenance in the Agrobacterium tumefaciens plant pathogen.
Journal
Nucleic acids research
ISSN
1362-4962 (Electronic)
ISSN-L
0305-1048
Publication state
Published
Issued date
28/10/2024
Peer-reviewed
Oui
Volume
52
Number
19
Pages
11519-11535
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Publication Status: ppublish
Abstract
The cell cycle-regulated DNA methyltransferase CcrM is conserved in most Alphaproteobacteria, but its role in bacteria with complex or multicentric genomes remains unexplored. Here, we compare the methylome, the transcriptome and the phenotypes of wild-type and CcrM-depleted Agrobacterium tumefaciens cells with a dicentric chromosome with two essential replication origins. We find that DNA methylation has a pleiotropic impact on motility, biofilm formation and viability. Remarkably, CcrM promotes the expression of the repABCCh2 operon, encoding proteins required for replication initiation/partitioning at ori2, and represses gcrA, encoding a conserved global cell cycle regulator. Imaging ori1 and ori2 in live cells, we show that replication from ori2 is often delayed in cells with a hypo-methylated genome, while ori2 over-initiates in cells with a hyper-methylated genome. Further analyses show that GcrA promotes the expression of the RepCCh2 initiator, most likely through the repression of a RepECh2 anti-sense RNA. Altogether, we propose that replication at ori1 leads to a transient hemi-methylation and activation of the gcrA promoter, allowing repCCh2 activation by GcrA and contributing to initiation at ori2. This study then uncovers a novel and original connection between CcrM-dependent DNA methylation, a conserved epigenetic regulator and genome maintenance in an Alphaproteobacterial pathogen.
Keywords
Agrobacterium tumefaciens/genetics, DNA Methylation, Genome, Bacterial, DNA Replication/genetics, Gene Expression Regulation, Bacterial, Bacterial Proteins/genetics, Bacterial Proteins/metabolism, Replication Origin/genetics, Promoter Regions, Genetic, Biofilms/growth & development, Operon/genetics, Site-Specific DNA-Methyltransferase (Adenine-Specific)
Pubmed
Web of science
Open Access
Yes
Create date
06/09/2024 10:11
Last modification date
31/10/2024 7:13