AK3 is a mitochondrial adenylate kinase that catalyzes GTP:AMP phosphotransferase activity, with an ability to use ITP as an alternative phosphate donor 1. The enzyme recycles GTP into GDP within the mitochondrial matrix, supporting energy metabolism in the tricarboxylic acid cycle. AK3 is widely expressed across tissues, with particularly high levels in heart, skeletal muscle, and liver 1. In clinical contexts, AK3 variants are associated with neurodegenerative disease, brain aneurysm, and metabolic disorders including diabetes mellitus and gestational diabetes. A recent whole-genome sequencing study identified AK3 among 24 prioritized genes in 9p deletion syndrome, with patients showing excess mitochondrial genome copy number, linking AK3 dosage to mitochondrial function 2. In breast cancer, AK3 expression is regulated by miR-96-5p and reduced AK3 levels correlate with worse overall survival, suggesting a protective role in cancer progression 3. The gene's role in maintaining mitochondrial nucleotide pools positions it as relevant to energy-dependent cellular processes, though specific therapeutic interventions targeting AK3 remain to be established.