Based on limited published evidence, ACTMAP (actin maturation protease) is a cysteine-type aminopeptidase that mediates post-translational maturation of actin. It specifically cleaves N-terminal acetylated methionine from immature cytoplasmic beta- and gamma-actins (ACTB, ACTG1) after translation 1, and cleaves N-terminal acetylated cysteine from muscle alpha-actins (ACTA1, ACTC1, ACTA2) following canonical N-terminal methionine removal. ACTMAP functions as a cysteine protease required for proper actin maturation, with recent studies identifying butynamide-based covalent inhibitors that selectively target its catalytic nucleophile 2.