OriDB Curated Paper

The S-phase checkpoint is required to respond to R-loops accumulated in THO mutants.

Belén Gómez-González, Irene Felipe-Abrio, Andrés Aguilera

Mol. Cell. Biol. (2009), 29(19):5203-13PubMed | PubMed Central | Mol. Cell. Biol.

Cotranscriptional R-loops are formed in yeast mutants of the THO complex, which functions at the interface between transcription and mRNA export. Despite the relevance of R-loops in transcription-associated recombination, the mechanisms by which they trigger recombination are still elusive. In order to understand how R-loops compromise genome stability, we have analyzed the genetic interaction of THO with 26 genes involved in replication, S-phase checkpoint, DNA repair, and chromatin remodeling. We found a synthetic growth defect in double null mutants of THO and S-phase checkpoint factors, such as the replication factor C- and PCNA-like complexes. Under replicative stress, R-loop-forming THO null mutants require functional S-phase checkpoint functions but not double-strand-break repair functions for survival. Furthermore, R-loop-forming hpr1Delta mutants display replication fork progression impairment at actively transcribed chromosomal regions and trigger Rad53 phosphorylation. We conclude that R-loop-mediated DNA damage activates the S-phase checkpoint, which is required for the cell survival of THO mutants under replicative stress. In light of these results, we propose a model in which R-loop-mediated recombination is explained by template switching.

OriDB annotation of this paper:

ARS assay

None curated.

2D gel

None curated.

ChIP of replication origin proteins

None curated.

Replication timing

None curated.

Replication in hydroxyurea

None curated.

Predicted origins

None curated.

Confirmed sequence element

None curated.

Predicted sequence element

None curated.