Structural comparison of the human mitochondrial and cytoplasmic serine hydroxymethyltransferase genes. Academic Article uri icon


  • Serine hydroxymethyltransferase (SHMT) catalyzes two reactions: the reversible interconversion of serine and tetrahydrofolate to gly(ine and 5,10-methylenetetrahydrofolate and the irreversible conversion of 5,I0methenyltetrahydrofolate to 5-formyltetrahydrofolate. The enzymes are present in both the cytoplasm and mitochondria of mammalian cells. The differential metabolic roles of the two SHMT isozymes is not well understood. To elucidate the individual roles of the SHMT isozymes in human cells, we have cloned the human genes encoding the SHMT isozymes and are studying the factors responsible for regulating their endogenous expression. The coding region of both genes are interrupted by ten introns, all of which follow the gt/ag rule. although only two of these introns are positionally conserved. The 5' regulatory consensus motifs present in the genes are distinct, and luciferase gene reporter assays suggest that the genes are not coordinately regulated. Sequence analysis of the two genes suggests that they may be capable of being expressed by "alternate protnoters: the functional roles of these alternative promoters are discdssed.

published proceedings


author list (cited authors)

  • Nasrallah, I. M., Girgis, S., & Stover, P. J.

complete list of authors

  • Nasrallah, IM||Girgis, S||Stover, PJ

publication date

  • December 1997