BioProject

Here we analysed the role of yeast Senataxin (Sen1) in coordinating replication with transcription and in protecting genome integrity. More...

Here we analysed the role of yeast Senataxin (Sen1) in coordinating replication with transcription and in protecting genome integrity. Senataxin is mutated in the two severe neurodegenerative diseases AOA2 and ALS4. We show that a fraction of Sen1/Senataxin DNA/RNA helicase associates with replication forks and protects the integrity of those fork encountering highly expressed RNAPII genes. sen1 mutants accumulate aberrant DNA structures and RNA-DNA hybrids while forks clash head-on with RNAPII transcription units and counteract recombinogenic events and accumulation of checkpoint signals. Nrd1, which acts togheter with Sen1 in trascription temination, is not recruited at replication forks. nrd1 mutants does not display replication defects, high genome instability and checkpoint activation observed in sen1 mutants The Sen1 function in replication can be therefore separable from its role in RNA processing. We propose a role for Sen1/Senataxin during chromosome replication in facilitating replisome progression across RNAPII transcribed genes thus preventing DNA-RNA hybrids accumulation when forks encounter nascent transcripts on the lagging strand template. Overall design: Chip on chip analysis was carried out as described (Bermejo et al., 2011), employing anti-Flag monoclonal antibody M2 (Sigma-Aldrich) Labelled probes were hybridized to Affymetrix S.cerevisiae Tiling 1.0 (P/N 900645) arrays and processed with TAS software. Less...