MonoADPribose

MonoADPribose is a molecule consisting of adenosine diphosphate (ADP) linked to a ribose sugar. It is a key component in the process of mono-ADP-ribosylation, a post-translational modification of proteins. This modification involves the transfer of a single ADP-ribose moiety from a donor molecule, typically nicotinamide adenine dinucleotide (NAD+), to a target protein.

The ADP-ribosylation process is catalyzed by a family of enzymes known as ADP-ribosyltransferases (ARTs). These enzymes play crucial roles in various cellular functions, including DNA repair, gene expression regulation, signal transduction, and protein degradation. The attachment of monoADPribose can alter the function of the target protein by changing its conformation, its interaction with other molecules, or its localization within the cell.

MonoADPribose can be attached to different amino acid residues on proteins, such as arginine, glutamine, or aspartate. The specific site of modification and the type of amino acid involved can influence the downstream effects of the modification. The reverse reaction, de-ADP-ribosylation, is carried out by enzymes called ADP-ribosylhydrolases (ARHs), which remove the monoADPribose group and restore the protein to its original state.

Dysregulation of monoADPribose modification has been implicated in a number of diseases, including cancer, neurodegenerative disorders, and inflammatory conditions. Therefore, understanding the mechanisms and biological significance of monoADPribose is an active area of research with potential implications for therapeutic development.