FUS forms liquid compartments at DNA damage sites and in the cytoplasm upon stress in a PAR interaction-dependent manner, while the ALS-FUS mutant can promote the aggregation of FUS protein-mediated liquid droplets, a common hallmark of FUS pathology in ALS and FTD (Patel et al., 2015). The gene discussed is FUS; the disease is amyotrophic lateral sclerosis.