PARP6 and viral infectious disease: This reaction, catalyzed by specific mono-ARTs including PARP3 and PARP6–PARP16 (with PARP13, which is encoded by ZC3HAV1, being enzymatically inactive; PARP7 is also known as TiPARP) (Fig. 1C), is involved in a variety of biological processes, including the regulation of cell signaling, intracellular membrane trafficking, metabolism, stress responses, viral infection, immune responses and tumorigenesis (Corda and Di Girolamo, 2003; Lüscher et al., 2022b; Morone and Grimaldi, 2024; Suskiewicz et al., 2023).