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.
Powered by Bioz
