The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)



Gene Review

SMT3  -  SUMO family protein SMT3

Saccharomyces cerevisiae S288c

Synonyms: D9719.15, Ubiquitin-like protein SMT3, YDR510W
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

High impact information on SMT3

  • The pattern of Smt3-coupled proteins in yeast changes markedly throughout the cell cycle, and specific conjugates accumulate in ulp1 mutants [1].
  • Our results also suggest that at early meiotic prophase, Zip1 interacts with Zip3-independent Smt3 conjugates (e.g., Top2) to promote nonhomologous centromere coupling [2].
  • Experiments with conditional uba2 mutants showed that Uba2p is required for Smt3p conjugation in vivo [3].
  • Moreover, recombinant yeast and mammalian UBC9 enzymes were found to form thioester complexes with SMT3 and SUMO-1, respectively [4].
  • The ubiquitin-like protein SMT3 from Saccharomyces cerevisiae and SUMO-1, its mammalian homolog, can be covalently attached to other proteins posttranslationally [4].

Biological context of SMT3

  • A human HSMT3 cDNA encoding a homolog of the yeast SMT3, a suppressor of MIF2 mutations in a centromere protein gene, was identified and sequenced [5].
  • Furthermore, UBA2 and AOS1 are both essential genes, providing additional evidence that they act in a distinct pathway whose role in cell viability is to conjugate Smt3p to other proteins [3].
  • The absence of Ubc9 or Smt3 also resulted in defects in chromosome segregation [6].
  • We also report an initial characterization of phenotypes associated with the SMT3/SUMO gene and the isolation of WSS1, a high-copy smt3 suppressor [7].
  • The role of yeast UBC9 in cell cycle progression may thus be mediated through its SMT3 conjugation activity [4].

Anatomical context of SMT3


Associations of SMT3 with chemical compounds

  • In this report, we show that Smt3 conjugation occurs at a single site in Dorsal (lysine 382), requires just the Smt3-activating and -conjugating enzymes, and is reversed by the deconjugating enzyme Ulp1 [8].

Physical interactions of SMT3

  • A subset of these Smt3p-modified proteins co-immunoprecipitated with the septin Cdc11p [9].
  • Segregation of the 2 microm circle requires two plasmid-encoded proteins, Rep1 and Rep2, which were found to colocalize with Ulp1 protein in the nucleus and interact with Smt3 in a two-hybrid assay [10].

Other interactions of SMT3

  • Inactivation of Ulp2 also suppresses several ulp1(ts) defects, and the double mutant accumulates far fewer Smt3-protein conjugates than either single mutant [11].
  • Smt3/SUMO and Ubc9 are required for efficient APC/C-mediated proteolysis in budding yeast [6].
  • Yeast Smt3 and its vertebrate homolog SUMO-1 are ubiquitin-like proteins (Ubls) that are reversibly ligated to other proteins [11].
  • Around the time of cytokinesis the Cdc3-Smt3 conjugate disappeared [12].
  • The level of this modification was affected by Smt3-specific protease mutation ulp1-ts or overexpression of ULP1 [13].

Analytical, diagnostic and therapeutic context of SMT3


  1. A new protease required for cell-cycle progression in yeast. Li, S.J., Hochstrasser, M. Nature (1999) [Pubmed]
  2. SUMO modifications control assembly of synaptonemal complex and polycomplex in meiosis of Saccharomyces cerevisiae. Cheng, C.H., Lo, Y.H., Liang, S.S., Ti, S.C., Lin, F.M., Yeh, C.H., Huang, H.Y., Wang, T.F. Genes Dev. (2006) [Pubmed]
  3. The ubiquitin-like protein Smt3p is activated for conjugation to other proteins by an Aos1p/Uba2p heterodimer. Johnson, E.S., Schwienhorst, I., Dohmen, R.J., Blobel, G. EMBO J. (1997) [Pubmed]
  4. The ubiquitin-like proteins SMT3 and SUMO-1 are conjugated by the UBC9 E2 enzyme. Schwarz, S.E., Matuschewski, K., Liakopoulos, D., Scheffner, M., Jentsch, S. Proc. Natl. Acad. Sci. U.S.A. (1998) [Pubmed]
  5. Cloning and expression of human homolog HSMT3 to yeast SMT3 suppressor of MIF2 mutations in a centromere protein gene. Mannen, H., Tseng, H.M., Cho, C.L., Li, S.S. Biochem. Biophys. Res. Commun. (1996) [Pubmed]
  6. Smt3/SUMO and Ubc9 are required for efficient APC/C-mediated proteolysis in budding yeast. Dieckhoff, P., Bolte, M., Sancak, Y., Braus, G.H., Irniger, S. Mol. Microbiol. (2004) [Pubmed]
  7. Genes involved in sister chromatid separation and segregation in the budding yeast Saccharomyces cerevisiae. Biggins, S., Bhalla, N., Chang, A., Smith, D.L., Murray, A.W. Genetics (2001) [Pubmed]
  8. Conjugation of Smt3 to dorsal may potentiate the Drosophila immune response. Bhaskar, V., Smith, M., Courey, A.J. Mol. Cell. Biol. (2002) [Pubmed]
  9. SUMO modification of septin-interacting proteins in Candida albicans. Martin, S.W., Konopka, J.B. J. Biol. Chem. (2004) [Pubmed]
  10. The 2 microm plasmid causes cell death in Saccharomyces cerevisiae with a mutation in Ulp1 protease. Dobson, M.J., Pickett, A.J., Velmurugan, S., Pinder, J.B., Barrett, L.A., Jayaram, M., Chew, J.S. Mol. Cell. Biol. (2005) [Pubmed]
  11. The yeast ULP2 (SMT4) gene encodes a novel protease specific for the ubiquitin-like Smt3 protein. Li, S.J., Hochstrasser, M. Mol. Cell. Biol. (2000) [Pubmed]
  12. Smt3, a SUMO-1 homolog, is conjugated to Cdc3, a component of septin rings at the mother-bud neck in budding yeast. Takahashi, Y., Iwase, M., Konishi, M., Tanaka, M., Toh-e, A., Kikuchi, Y. Biochem. Biophys. Res. Commun. (1999) [Pubmed]
  13. Yeast Ulp1, an Smt3-specific protease, associates with nucleoporins. Takahashi, Y., Mizoi, J., Toh-E, A., Kikuchi, Y. J. Biochem. (2000) [Pubmed]
  14. SUMO conjugation and deconjugation. Schwienhorst, I., Johnson, E.S., Dohmen, R.J. Mol. Gen. Genet. (2000) [Pubmed]
WikiGenes - Universities