Nucleolar-nucleoplasmic shuttling of the RNA-binding macrodomain-containing TARG1 is controlled by DNA damage-induced poly-ADP-ribose and implies functions in ribosome biogenesis

In this project we employed affinity purification mass spectrometry to determine the interactome of the macrodomain containing protein TARG1/OARD1. TARG1 functions as a hydrolase towards mono-ADP-ribosylation (MARylation). TARG1 sowed strong binding to ribosomes and proteins associated with rRNA processing. However, when poly-ADP- ribosylation (PARylation) was present in the cellular lysate, TARG1 was found to interacts with DNA repair and chromatin-associated proteins, including ARTD1, in a PARylation-dependent manner. PARylation events also lead to a change in the subcellular localization of TARG1, which was found to reside in the nucleolus in resting cells, and shuttle to the nucleoplasm upon PARylation