Fig. 3: LLPS in the compartmentalization of damaged DNA.
From: Biomolecular condensates as arbiters of biochemical reactions inside the nucleus
a Mammalian PARP-1 is an early responder at DNA damage sites and synthetizes long negatively charged PAR chains that interact with positively charged RGG motifs present on FUS proteins. LLPS of FUS allows the compartmentalization of the DNA damage site and the exclusion of specific factors, such as 53BP1. Upon PARG activation and FUS phosphorylation, the FUS condensate disassembles and allows for the enrichment and subsequent LLPS of 53BP1. This phenomenon is mediated, at least in part, by the oligomerization domain of 53BP1. The enrichment of the mediator component MED1 and RNA Pol II in either compartment remains to be determined. b Budding yeast Rad52 forms biomolecular condensates at sites of DNA damage. The condensates can concentrate tubulin and drive the polymerization of microtubule filaments. The filaments help mobilize damaged DNA inside of the nucleus to promote repair.
