AK9 (Adenylate Kinase 9): Adenylate kinase is a gene that encodes an enzyme from the adenylate kinase family, which catalyzes the reversible transfer of phosphate groups between adenine nucleotides, primarily ATP and AMP. AK9 is located in the mitochondria, where it supports energy metabolism and nucleotide balance. By facilitating the conversion between ATP and AMP, it helps regulate cellular energy levels and contributes to processes such as mitochondrial function, apoptosis, and stress responses. Dysregulation of AK9 may affect metabolic and cellular homeostasis.