Dataset Information

Bacillus subtilis RarA Acts as a Positive RecA Accessory Protein.

ABSTRACT: Ubiquitous RarA AAA+ ATPases play crucial roles in the cellular response to blocked replication forks in pro- and eukaryotes. Here, we provide evidence that absence of RarA reduced the viability of ?recA, ?recO, and recF15 cells during unperturbed growth. The rarA gene was epistatic to recO and recF genes in response to H2O2- or MMS-induced DNA damage. Conversely, the inactivation of rarA partially suppressed the HR defect of mutants lacking end-resection (?addAB, ?recJ, ?recQ, ?recS) or branch migration (?ruvAB, ?recG, ?radA) activity. RarA contributes to RecA thread formation, that are thought to be the active forms of RecA during homology search. The absence of RarA reduced RecA accumulation, and the formation of visible RecA threads in vivo upon DNA damage. When ?rarA was combined with mutations in genuine RecA accessory genes, RecA accumulation was further reduced in ?rarA ?recU and ?rarA ?recX double mutant cells, and was blocked in ?rarA recF15 cells. These results suggest that RarA contributes to the assembly of RecA nucleoprotein filaments onto single-stranded DNA, and possibly antagonizes RecA filament disassembly.

SUBMITTER: Romero H

PROVIDER: S-EPMC7031210 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Bacillus subtilis RarA Acts as a Positive RecA Accessory Protein.

Romero Hector H Serrano Ester E Hernández-Tamayo Rogelio R Carrasco Begoña B Cárdenas Paula P PP Ayora Silvia S Graumann Peter L PL Alonso Juan C JC

Frontiers in microbiology 20200213

Ubiquitous RarA AAA+ ATPases play crucial roles in the cellular response to blocked replication forks in pro- and eukaryotes. Here, we provide evidence that absence of RarA reduced the viability of ΔrecA, ΔrecO, and recF15 cells during unperturbed growth. The rarA gene was epistatic to recO and recF genes in response to H2O2- or MMS-induced DNA damage. Conversely, the inactivation of rarA partially suppressed the H ...[more]

PMID: 32117122

Similar Datasets

Project description:UnlabelledEfficient duplication of genomes depends on reactivation of replication forks outside the origin. Replication restart can be facilitated by recombination proteins, especially if single- or double-strand breaks form in the DNA. Each type of DNA break is processed by a distinct pathway, though both depend on the RecA protein. One common obstacle that can stall forks, potentially leading to breaks in the DNA, is transcription. Though replication stalling by transcription is prevalent, the nature of DNA breaks and the prerequisites for replication restart in response to these encounters remain unknown. Here, we used an engineered site-specific replication-transcription conflict to identify and dissect the pathways required for the resolution and restart of replication forks stalled by transcription in Bacillus subtilis. We found that RecA, its loader proteins RecO and AddAB, and the Holliday junction resolvase RecU are required for efficient survival and replication restart after conflicts with transcription. Genetic analyses showed that RecO and AddAB act in parallel to facilitate RecA loading at the site of the conflict but that they can each partially compensate for the other's absence. Finally, we found that RecA and either RecO or AddAB are required for the replication restart and helicase loader protein, DnaD, to associate with the engineered conflict region. These results suggest that conflicts can lead to both single-strand gaps and double-strand breaks in the DNA and that RecA loading and Holliday junction resolution are required for replication restart at regions of replication-transcription conflicts.ImportanceHead-on conflicts between replication and transcription occur when a gene is expressed from the lagging strand. These encounters stall the replisome and potentially break the DNA. We investigated the necessary mechanisms for Bacillus subtilis cells to overcome a site-specific engineered conflict with transcription of a protein-coding gene. We found that the recombination proteins RecO and AddAB both load RecA onto the DNA in response to the head-on conflict. Additionally, RecA loading by one of the two pathways was required for both replication restart and efficient survival of the collision. Our findings suggest that both single-strand gaps and double-strand DNA breaks occur at head-on conflict regions and demonstrate a requirement for recombination to restart replication after collisions with transcription.

Dataset Information

Bacillus subtilis RarA Acts as a Positive RecA Accessory Protein.

Publications

<i>Bacillus subtilis</i> RarA Acts as a Positive RecA Accessory Protein.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets