Human ISWI complexes are targeted by SMARCA5 ATPase and SLIDE domains to help resolve lesion-stalled transcription.
Bottom Line: Chromatin compaction of deoxyribonucleic acid (DNA) presents a major challenge to the detection and removal of DNA damage.Using live cell imaging, we identify a novel function for two distinct mammalian ISWI adenosine triphosphate (ATP)-dependent chromatin remodeling complexes in resolving lesion-stalled transcription.Our studies support a model in which SMARCA5 targeting to DNA damage-stalled transcription sites is controlled by an ATP-hydrolysis-dependent scanning and proofreading mechanism, highlighting how SWI2/SNF2 chromatin remodelers identify and bind nucleosomes containing damaged DNA.
Affiliation: Department of Genetics, Medical Genetics Cluster, Cancer Genomics Netherlands, Erasmus MC, Rotterdam, 3015 GE, The Netherlands.Show MeSH
Related in: MedlinePlus
Mentions: Next, we determined which SMARCA5 domains are responsible for its damage accumulation and subsequent re-localization. SMARCA5 harbors an ATPase domain at the N-terminus, for ATP hydrolysis, and HAND, SANT and SLIDE domains at the C-terminus (Figure 4A), which were suggested to associate with linker DNA to control nucleosome sliding (52,53). To test involvement of the ATPase domain, we introduced an inactivating mutation by replacing Lys211 in the nucleotide-binding motif with Arg (37). Intriguingly, ATPase dead SMARCA5-GFP did not localize to the center of UV damage and was even depleted from this area (Figure 4A and B). Furthermore, a reduced and delayed recruitment to the periphery of the damage was observed. This suggests that ATP hydrolysis directs SMARCA5 targeting to UV-C-induced DNA damage.
Affiliation: Department of Genetics, Medical Genetics Cluster, Cancer Genomics Netherlands, Erasmus MC, Rotterdam, 3015 GE, The Netherlands.