Description: Ubiquitin is a highly conserved 76kDa protein which is ligated to many proteins in both monomeric and polymeric forms. Ubiquitin polymers (polyubiquitin) can be found in several varieties depending on which of its 7 lysine residues is the site of ligation. The two most common polymer chains are linked via an isopeptide bond between glycine-76 and either lysine-48 (K-48) or lysine-63 (K-63). K-48-linked polyubiquitination typically results in targeting the protein to the 26S proteosome resulting in proteolysis, although recently exceptions to this have been observed. In contrast, K-63-linked polyubiquitination results in signals related to intracellular trafficking, cell signaling, ribosomal biogenesis, and DNA damage repair. There are also reports that K63-linked polyubiquitin is involved in proteosome-independent proteolysis via autophagy.
HWA4C4 reacts specifically with the isopeptide linkage region of lysine-63-linked polyubiquitin. It does not react with other forms of ubiquitin including ubiquitin monomer and lysine-48-linked chains.
Applications Reported: This HWA4C4 antibody has been reported for use in immunoblotting (WB).
Applications Tested: This HWA2-8°C4 antibody has been tested by immunoblot of lysine-63-linked polyubiquitin chains. This can be used at less than or equal to 2 µg/mL. It is recommended that the antibody be carefully titrated for optimal performance in the assay of interest.
Purity: Greater than 90%, as determined by SDS-PAGE.
Aggregation: Less than 10%, as determined by HPLC.
Filtration: 0.2 µm post-manufacturing filtered.
Ubiquitin is a conserved 76 amino acid polypeptide and can affect proteasomal degradation of the protein it is bound to, or mediate interactions with other proteins related to post-translational modifications. The degradation of cellular regulatory proteins by the Uubiquitin pathway is important as it controls the cellular growth and proliferation. Ubiquitin-dependent proteolysis occurs after a covalent attachment of the peptide to a lysine residue of a protein, which involves three enzymatic reactions: E1, E2 and E3. The first reaction involves ubiquitin-activating enzyme. The third reaction uses enzyme ubiquitin ligase (E3) to transfer the activated ubiquitin from E2 to a lysine residue on a protein, or directly transfers the ubiquitin from E2 to the substrate.
For Research Use Only. Not for use in diagnostic procedures. Not for resale without express authorization.
Protein Aliases: epididymis secretory protein Li 50; polyubiquitin B; Polyubiquitin-B; Ubiquitin
Gene Aliases: HEL-S-50; UBB
UniProt ID: (Human) P0CG47
Entrez Gene ID: (Human) 7314