N-alpha-acetyltransferase that specifically mediates the acetylation of the acidic amino terminus of processed forms of beta- and gamma-actin (ACTB and ACTG, respectively) (PubMed:29581253, PubMed:30028079). N-terminal acetylation of processed beta- and gamma- actin regulates actin filament depolymerization and elongation (PubMed:29581253). In vivo, preferentially displays N-terminal acetyltransferase activity towards acid N-terminal sequences starting with Asp-Asp-Asp and Glu-Glu-Glu (PubMed:29581253, PubMed:30028079). In vitro, shows high activity towards Met-Asp-Glu-Leu and Met-Asp-Asp-Asp (PubMed:10644992, PubMed:29581307). May act as a tumor suppressor (PubMed:10644992). {ECO:0000269|PubMed:10644992, ECO:0000269|PubMed:29581253, ECO:0000269|PubMed:29581307, ECO:0000269|PubMed:30028079}. This is the function of ENSG00000243477 (NAA80, N-alpha-acetyltransferase 80, NatH catalytic subunit).