Small ubiquitin-like modifier-1 (SUMO-1) modification of thymidylate synthase and dihydrofolate reductase. Academic Article uri icon


  • BACKGROUND: Impairments in folate-mediated one-carbon metabolism are associated with pathologies and developmental anomalies, including cardiovascular disease, cancer, neurological disorders and neural tube defects. The mechanisms that detail the role of folate and one-carbon metabolism in these disorders remain to be established. Folate deficiency impairs folate-dependent thymidylate biosynthesis resulting in depleted dTTP levels, increased rates of uracil incorporation into DNA and genomic instability. Folate-dependent enzymes involved in the de novo thymidylate pathway include cytoplasmic serine hydroxymethyltransferase (cSHMT), thymidylate synthase (TS) and dihydrofolate reductase (DHFR). Previously, we demonstrated that cSHMT-derived folate activated one-carbon units are preferentially incorporated into thymidylate, and we provided evidence that this was achieved through modification with small ubiquitin-like modifier (SUMO) enabling SUMO-dependent nuclear localization of cSHMT during S-phase. METHODS AND RESULTS: Here, we provide evidence that TS and DHFR are also substrates for UBC9-catalyzed SUMOylation in vitro by SUMO-1. CONCLUSIONS: The SUMOylation of cSHMT, TS and DHFR provides a mechanism by which all three enzymes in the thymidylate synthesis pathway are directed and compartmentalized in the nucleus.

published proceedings

  • Clin Chem Lab Med

author list (cited authors)

  • Anderson, D. D., Woeller, C. F., & Stover, P. J.

citation count

  • 54

complete list of authors

  • Anderson, Donald D||Woeller, Collynn F||Stover, Patrick J

publication date

  • January 2007