MTHFD2 (Methylenetetrahydrofolate Dehydrogenase 2): MTHFD2 is an enzyme that plays a key role in the mitochondrial one-carbon metabolic pathway. It is essential for nucleotide biosynthesis, methylation reactions, and amino acid homeostasis. MTHFD2 is highly expressed in rapidly dividing cells, including cancer cells, where it supports the production of purines and thymidylate, critical for DNA replication and repair. Its role in cellular metabolism and proliferation underscores its importance in growth and development, and its selective expression in tumors makes it a potential therapeutic target.