• Purity

  >95%, by SDS-PAGE under reducing conditions and visualized by Colloidal Coomassie? Blue stain

• Activity

  SUMO chains form     in vitro and     in vivo and their linkage and functional relevance is an area of increasingly intense investigation. SUMO lysine to arginine mutants are ideal for investigating SUMO chain linkages. Recombinant Human SUMO2 Mutant K11R prevents the modification of K11 within SUMO and/or poly-SUMO chains. Reaction conditions will need to be optimized for each specific application. We recommend an initial Recombinant Human SUMO2 Mutant K11R concentration of 10-50 μM.

• Source

  E. coli-derived

• Accession #

• Predicted Molecular Mass

  11 kDa

Background: SUMO2

Human Small Ubiquitin-like Modifier 2 (SUMO2), also known as Sentrin2 and SMT3B is synthesized as a 95 amino acid (aa), propeptide with a predicted 11 kDa. SUMO2 contains a two aa C-terminal prosegment and an 18 aa N-terminal protein interacting region between aa 33-50. Human SUMO2 shares 100% aa sequence identity with mouse SUMO2. SUMO2 also has very high aa sequence identity with SUMO3 and SUMO4, 86% and 85%, respectively. SUMO2 shares only 44% aa sequence identity with SUMO1. SUMOs are a family of small, related proteins that can be enzymatically attached to a target protein by a post-translational modification process termed SUMOylation (1-3). All SUMO proteins share a conserved Ubiquitin domain and a C-terminal diglycine cleavage/attachment site. Following prosegment cleavage, the C-terminal glycine residue of SUMO2 is enzymatically attached to a lysine residue on a target protein. In humans, SUMO2 is conjugated to a variety of molecules in the presence of the SAE1/UBA2 SUMO-activating (E1) enzyme and the UBE2I/Ubc9 SUMO-conjugating (E2) enzyme (4,5). In yeast, the SUMO-activating (E1) enzyme is Aos1/Uba2p (6). Because of the high level of aa sequence identity most studies report effects of SUMO2/3. For example, post-translational addition of SUMO2/3 was shown to modulate the function of ARHGAP21, a RhoGAP protein known to be involved in cell migration (7). Other reports indicate that the SUMOylation with SUMO2/3, but not SUMO1, may represent an important mechanism to protect neurons during episodes of cerebral ischemia (8,9). However, studies suggest that SUMO2/3 expression is regulated in an isoform-specific manner since oxidative stress downregulated the transcription of SUMO3 but not SUMO2 (10).

Mutation of lysine 11 to arginine renders SUMO2 unable to form poly-SUMO multimers and is useful to investigate mono-SUMOylation or can be used to reduce poly-SUMO chain formation. Human SUMO2 contains the VK11TE sequence which allows for the formation of poly-SUMO chains. K11 is the conserved lysine that becomes modified and is the point of attachment for the C-terminal glycine of the preceding SUMO2. The function of SUMO chains has not yet been fully elucidated.

• References:

1. Desterro, J.M. et al. (1997) FEBS. Lett. 417:297.

2. Bettermann, K. et al. (2012) Cancer Lett. 316:113.

3. Praefcke, G.J. et al. (2012) Trends Biochem. Sci. 37:23.

4. Okuma, T. et al. (1999) Biochem. Biophys. Res. Commun. 254:693.

5. Tatham, M.H. et al. (2001) J. Biol. Chem. 276:35368.

6. Johnson, E.S. et al. (1997) EMBO J. 16:5509.

7. Bigarella, C.L. et al. (2012) FEBS Lett. 586:3522.

8. Datwyler, A.L. et al. (2012) J. Cereb. Blood Flow Metab. 31:2152.

9. Wang, Z. et al. (2012) Protein Expr. Purif. 82:174.

10. Sang, J. et al. (2012) Biochem. J. 435:489.

• Long Name:

  Small Ubiquitin-like Modifier 2

• Entrez Gene IDs:

  6613 (Human)

• Alternate Names:

  HSMT3; MGC117191; sentrin 2; Sentrin-2; small ubiquitin-like modifier 2; small ubiquitin-related modifier 2; SMT3 (suppressor of mif two 3, yeast) homolog 2; SMT3 homolog 2; SMT3 suppressor of mif two 3 homolog 2 (S. cerevisiae); SMT3 suppressor of mif two 3 homolog 2 (yeast); SMT3A; SMT3B; SMT3H2; SUMO2; SUMO-2; SUMO3; SUMO-3; Ubiquitin-like protein SMT3A; ubiquitin-like protein SMT3B