In parallel, we found that Rad51 swiftly accumulated at replication forks following HU treatment, whereas Nbs1 association with the forks was mostly unaffected.
In this study, we further demonstrated that the S14 residue in Rad51 is important for protection of nascent DNA at stalled replication forks following HU treatment.
This asymmetric stalled fork configuration with advanced leading strand and stable replisome- or helicase-fork complexes may facilitate, in some way, fork restart following HU removal and checkpoint deactivation.
Under these conditions a replication-pausing complex stabilizes the stalled forks, while a checkpoint response is activated to halt cell-cycle progression and to allow fork restart following DNA repair (Branzei and Foiani, 2005).
But my husband, Steve, and I couldn't stay: we were heading north to the Roaring Fork Valley, following all this growing local goodness on its journey from field to plate.
To this end, we measured replication fork velocity following knockdown of SMARCA5.
In this regard, one previous report suggested that BRCA2 mutant cells are particularly susceptible to replication fork collapse following prolonged HU treatment [ 13].
Homologs of SLX4 in model organisms were initially identified as necessary for replication fork restart following exposure to DNA-damaging agents [ 15].
As described for Hdacs1,2, we performed molecular combing analysis to determine changes in the replication fork rate following knockdown of SMARCA5 in the absence or presence of hydroxyurea.
In addition to cell cycle regulation, CHK1 has been implicated also in maintaining replication fork integrity following replication inhibition and CHK1 inhibition or genetic downregulation leads to accumulation of DNA double strand breaks (DSBs) in S-phase cells [ 40, 48].
