Title: Mutant FUS causes DNA ligation defects to inhibit oxidative damage repair in Amyotrophic Lateral Sclerosis.

Authors: Wang, Haibo; Guo, Wenting; Mitra, Joy; Hegde, Pavana M; Vandoorne, Tijs; Eckelmann, Bradley J; Mitra, Sankar; Tomkinson, Alan E; Van Den Bosch, Ludo; Hegde, Muralidhar L

Published In Nat Commun, (2018 Sep 11)

Abstract: Genome damage and defective repair are etiologically linked to neurodegeneration. However, the specific mechanisms involved remain enigmatic. Here, we identify defects in DNA nick ligation and oxidative damage repair in a subset of amyotrophic lateral sclerosis (ALS) patients. These defects are caused by mutations in the RNA/DNA-binding protein FUS. In healthy neurons, FUS protects the genome by facilitating PARP1-dependent recruitment of XRCC1/DNA Ligase IIIα (LigIII) to oxidized genome sites and activating LigIII via direct interaction. We discover that loss of nuclear FUS caused DNA nick ligation defects in motor neurons due to reduced recruitment of XRCC1/LigIII to DNA strand breaks. Moreover, DNA ligation defects in ALS patient-derived iPSC lines carrying FUS mutations and in motor neurons generated therefrom are rescued by CRISPR/Cas9-mediated correction of mutation. Our findings uncovered a pathway of defective DNA ligation in FUS-linked ALS and suggest that LigIII-targeted therapies may prevent or slow down disease progression.

PubMed ID: 30206235

MeSH Terms: Amyotrophic Lateral Sclerosis/genetics*; Amyotrophic Lateral Sclerosis/pathology; CRISPR-Cas Systems/genetics; Cell Line; DNA Damage/genetics*; DNA Ligases/metabolism; DNA Repair/genetics*; DNA/metabolism*; Gene Knockout Techniques; Genes, Dominant; Humans; Induced Pluripotent Stem Cells/metabolism; Models, Biological; Mutation/genetics*; Oxidative Stress*; Poly(ADP-ribose) Polymerases/metabolism; RNA-Binding Protein FUS/genetics*; Reactive Oxygen Species/metabolism; X-ray Repair Cross Complementing Protein 1/metabolism