MCAT (malonyl-CoA-acyl carrier protein transacylase) is a mitochondrial enzyme that catalyzes the transfer of malonyl moieties from malonyl-CoA to the phosphopantetheine arm of mitochondrial acyl carrier protein (NDUFAB1), suggesting a role in mitochondrial fatty acid biosynthesis 12. Beyond its metabolic function, MCAT also serves as a mitochondrial small ribosomal subunit assembly factor, indicating dual roles in both metabolism and ribosome biogenesis 3. The enzyme is localized to the mitochondrial matrix and participates in fatty acid biosynthetic processes as well as fatty acid beta-oxidation pathways. MCAT is associated with optic atrophy 15, though the specific disease mechanisms remain unclear from the available literature. The gene is located on chromosome 22 and its protein product contains RNA binding capabilities and RNA folding chaperone activity. While the provided abstracts discuss various uses of the MCAT acronym in other contexts (dental procedures, medical education, transcription factors), these are unrelated to the mitochondrial transacylase gene function.