• Purity

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

• Activity

  Ubiquitin chains vary in length, linkage, and function. K63-linked His6-Poly-Ubiquitin Chains (Ub2-7) are ideal for investigating Ubiquitin-binding proteins and as substrates for Ubiquitin-specific isopeptidases. Reaction conditions will need to be optimized for each specific application. IMPORTANT: Heating this product in SDS-PAGE buffer or terminating reactions containing this product with heated SDS-PAGE buffer could lead to unexpected, high apparent molecular weight banding or smearing on gels that is not representative of product purity. For optimal results, we recommend incubation in SDS-PAGE buffer + DTT at<40 °C for 20 minutes prior to gel electrophoresis.  

• Source

  E. coli-derived Contains a 6-His tag

• Accession #

• Predicted Molecular Mass

  19 kDa (Ub2), 29 kDa (Ub3), 38 kDa (Ub4), 48 kDa (Ub5), 57 kDa (Ub6), and 67 kDa (Ub7)

Background: Poly-Ubiquitin

Poly-Ubiquitin chains are composed of Ubiquitin monomers that are covalently linked through  isopeptide bonds, which typically form between a lysine residue of one Ubiquitin molecule and the C-terminal glycine residue of another Ubiquitin molecule (1). Each human Ubiquitin monomer is 76 amino acids (aa) in length and shares 96% and 100% aa identity with yeast and mouse Ubiquitin, respectively (2). Seven of the 76 aa in Ubiquitin are lysine residues that can participate in poly-Ubiquitin chain formation. Linkage through specific lysine residues is thought to serve as a signal that affects protein degradation, signaling, trafficking, and other cellular processes (3-8).

Linkage specific poly-Ubiquitin chains are used to investigate mechanisms of chain recognition, binding and hydrolysis by the proteasome, deubiquitinating enzymes, E3 ligases or other proteins that contain Ubiquitin-associated domains (UBAs) or ubiquitin-interacting motifs (UIMs). Lys63-linked poly-Ubiquitin has been implicated in several non-degradative processes such as receptor endocytosis and sorting, translation, DNA damage repair, the stress response and signaling in theNF kappa B pathway. This product is formed with wild-type human recombinant Ubiquitin and linkage-specific enzymes. This mixture of poly-Ubiquitin chains contains di-Ubiquitin and higher MW species; mono-Ubiquitin has been removed.

The His6-tag is convenient for metal chelate affinity purification and immuno-detection using His6-specific antibodies.

• References:

1. Scheffner, M. et al. (1995) Nature 373:81.

2. Sharp, P.M. & W.-H. Li (1987) Trends Ecol. Evol. 2:328.

3. Behrends, C. & J.W. Harper (2011) Nat. Struct. Mol. Biol. 18:520.

4. Greene, W. et al. (2012) PLoS Pathog. 8:e1002703.

5. Henry, A.G. et al. (2012) Dev. Cell 23:519.

6. Tong, X. et al. (2012) J. Biol. Chem. 287:25280.

7. Wei, W. et al. (2004) Nature 428:194.

8. Zhang, J. et al. (2012) J. Biol. Chem. 287:28646.

• Alternate Names:

  PolyUbiquitin; Poly-Ubiquitin