Acetylation of lysine residues in proteins can mediate protein-protein interactions, although few structural mechanisms of acetylation-dependent protein recognition have been elucidated. A common form of protein acetylation is N-terminal acetylation, which occurs cotranslationally for an estimated 30 to 90% of eukaryotic proteins. It is unclear how an N-terminally acetylated amino acid directly mediates protein-protein interactions. Scott et al. report that N-terminal acetylation of the E2 enzyme, Ubc12, dictates distinctive E3-mediated Nedd8 ligation to cullins. This mechanism of protein regulation connects protein acetylation with posttranslational modification by ubiquitin-like proteins.
D. C. Scott, J. K. Monda, E. J. Bennett, J. W. Harper, B. A. Schulman, N-terminal acetylation acts as an avidity enhancer within an interconnected multiprotein complex. Science 334, 674–678 (2011). [Abstract] [Full Text]