ADP-ribosyltransferase catalyzes the ADP-ribosylation of arginine residues in proteins. Mono-ADP-ribosylation is a posttranslational modification of proteins that is interfered with by a variety of bacterial toxins including cholera, pertussis, and heat-labile enterotoxins of E. coli. The amino acid sequence consists of predominantly hydrophobic N- and C-terminal regions, which is characteristic of glycosylphosphatidylinositol (GPI)-anchored proteins. This gene was previously designated ART2. ART1 (ADP-Ribosyltransferase 1) is a Protein Coding gene. Among its related pathways are Defensins and Innate Immune System. GO annotations related to this gene include NAD+ ADP-ribosyltransferase activity and NAD(P)+-protein-arginine ADP-ribosyltransferase activity. An important paralog of this gene is ART5.