Fig. 1

Biological role of SHMT. a Serine–glycine interconversion catalyzed by SHMT. THF = tetrahydrofolate, CH₂-THF = N-5,N-10-methylenetetrahydrofolate. The red dot highlights the carbon that is transferred from Ser to THF. b Schematic overview of hSHMT function. MTHFD = methylenetetrahydrofolate dehydrogenase-cyclohydrolase, CH₂-THF = N-5,N-10-methylenetetrahydrofolate, CH⁺-THF = 5,10-methenyltetrahydrofolate, CHO-THF = 10-formyltetrahydrofolate, NADP⁺ = Nicotinamide adenine dinucleotide phosphate, NADPH = NADP⁺ reduced form. c SHMT, dihydrofolate reductase (DHFR), and thymidylate synthase (TS) in the folate cycle. THF = tetrahydrofolate, CH₂-THF = 5,10-methylenetetrahydrofolate, DHF = dihydrofolate, FdUMP = fluorodeoxyuridine-5′-monophosphate, dUMP = deoxyuridine monophosphate, dTMP = deoxythymidine monophosphate