ADP‐ribosylation: new facets of an ancient modification

Rapid response to environmental changes is achieved by uni‐ and multicellular organisms through a series of molecular events, often involving modification of macromolecules, including proteins, nucleic acids and lipids. Amongst these, ADP‐ribosylation is of emerging interest because of its ability to modify different macromolecules in the cells, and its association with many key biological processes, such as DNA‐damage repair, DNA replication, transcription, cell division, signal transduction, stress and infection responses, microbial pathogenicity and aging. In this review, we provide an update on novel pathways and mechanisms regulated by ADP‐ribosylation in organisms coming from all kingdoms of life. ADP‐ribosyltransferases (ARTs) utilise NAD+ as a substrate to modify different molecular targets and control wide variety of processes in organisms of all domains of life.