ADPribosilasyonu

ADPribosilasyonu is a fundamental post-translational modification that plays a crucial role in numerous cellular processes. This enzymatic process involves the transfer of one or more ADP-ribose units from NAD+ to a target protein. The modification can occur on various amino acid residues, including aspartate, glutamate, lysine, arginine, cysteine, and even to the C-terminus of proteins. The enzymes responsible for catalyzing ADPribosylation are known as ADP-ribosyltransferases (ARTs). These enzymes can add a single ADP-ribose moiety (mono-ADP-ribosylation) or multiple ADP-ribose units, forming long chains (poly-ADP-ribosylation).

The functions of ADPribosylation are diverse and context-dependent. Mono-ADP-ribosylation has been implicated in regulating protein-protein interactions, enzyme activity, and cellular signaling pathways. Poly-ADP-ribosylation, particularly catalyzed by Poly(ADP-ribose) polymerase (PARP) enzymes, is heavily involved in DNA repair, genome stability, and cell death. The dynamic nature of ADPribosylation is also important, as it can be reversed by specific enzymes called ADP-ribosylhydrolases, allowing for fine-tuning of cellular responses. Dysregulation of ADPribosylation has been linked to various diseases, including cancer, neurodegenerative disorders, and inflammatory conditions, highlighting its significance in maintaining cellular homeostasis.