Component of the NatC N-terminal acetyltransferase, which catalyzes acetylation of the N-terminus Met of L-A virus Gag protein. MAK31 is necessary for the structural stability of L-A double-stranded RNA-containing particles. Necessary for growth at 37 degrees Celsius as well as for maintenance of the killer plasmid. Component of the N-terminal acetyltransferase C (NatC) complex, which is composed of MAK3, MAK10 and MAK31. Present with 2140 molecules/cell in log phase SD medium.