The SOG pathway is depicted as the combination of serine, one-carbon cycle and glycine cleavage all acting together in tumour cells. Glycolysis is upregulated in tumour cells, thus serine is synthesized from 3-phosphoglycerate whichis then coverted to glycine bya cytosolic serine hydroxymethyltransferase. Serine and glycine can also be transported into the mitochondria. Serine can be converted to glycine in the mitochondria where glycine can be incorporated into the glycine cleavage cycle. The serine reaction that yields glycine also produces 5,10-Methylene-THF which is incorporated into the one-carbon cycle. L-serine in mitochodria reacts with THF leading to the mitochondrial ne carbon cycle and the production of NADPH used in the transport of hydrogen ions into the mitochondria. ATP synthase is used to transport hydrogen outside of the mitochondria, generating ATP in the process. The SOG pathway is predicted to be mainly active in tumour cells with decreased activity from the pyruvate kinase protein.

The oncogenic action of Serine: serine, one carbon cycle glycine synthesis (SOG) References