PARP14 and PARP9/DTX3L regulate interferon-induced ADP-ribosylation
Pulak Kar, Chatrin Chatrin, Nina Đukić, Osamu Suyari, M. Schuller, Kang Zhu, Evgeniia Prokhorova, Nicolas Bigot, Domagoj Baretić, Juraj Ahel, Jonas D. Elsborg, Michael L. Nielsen, Tim Clausen, Sébastien Huet, Mario Niepel, Sumana Sanyal, Dragana Ahel, Rebecca Smith, Ivan Ahel
Abstract
PARP-catalysed ADP-ribosylation (ADPr) is important in regulating various cellular pathways. Until recently, PARP-dependent mono-ADP-ribosylation has been poorly understood due to the lack of sensitive detection methods. Here, we utilised an improved antibody to detect mono-ADP-ribosylation. We visualised endogenous interferon (IFN)-induced ADP-ribosylation and show that PARP14 is a major enzyme responsible for this modification. Fittingly, this signalling is reversed by the macrodomain from SARS-CoV-2 (Mac1), providing a possible mechanism by which Mac1 counteracts the activity of antiviral PARPs. Our data also elucidate a major role of PARP9 and its binding partner, the E3 ubiquitin ligase DTX3L, in regulating PARP14 activity through protein-protein interactions and by the hydrolytic activity of PARP9 macrodomain 1. Finally, we also present the first visualisation of ADPr-dependent ubiquitylation in the IFN response. These approaches should further advance our understanding of IFN-induced ADPr and ubiquitin signalling processes and could shed light on how different pathogens avoid such defence pathways.