CycLex Poly-Ubiquitinated Protein ELISA Kit

The ubiquitin-proteasome pathway is the principle pathway of proteolysis in eukaryotic cells and may contribute to controlling the intracellular levels of a variety of short-lived proteins (1-3), in addition to degrading abnormal proteins in the cytosol and nucleus. Protein substrates are marked with a poly-ubiquitin chain (4) and then degraded to peptides and free ubiquitin by a large multicatalytic complex, the proteasome, which exists within all eukaryotic cells (1-3). Numerous examples of regulatory proteins have been found to undergo ubiquitin-dependent proteolysis. Protein substrates of the ubiquitin-proteasome pathway include a number of cell regulatory molecules, such as cyclins, the Myc oncogene protein, and p53, and the regulated degradation of these molecules has been linked to the control of cell proliferation and cell cycle progression (5-7). By controlling the intracellular levels of such proteins, the activity of the ubiquitin-proteasome pathway might also be linked to apoptosis. In a recent decade, a variety of reversible (8) and irreversible (11) inhibitors of the 20 S proteasome have been identified that can enter mammalian cells and inhibit degradation of proteins by the ubiquitin-proteasome pathway. One group of such inhibitors are peptide aldehydes, e.g. MG132 which reversibly bind to active sites and inhibit cleavage of hydrophobic or acidic substrates (8). A more specific inhibitor is the naturally occurring bacterial compound, lactacystin, which covalently modifies threonine residues in the proteasome's active site and does not seem to affect any other known protease (11). Such agents can inhibit protein degradation (8-11) and major histocompatibility class I antigen presentation (8) in a variety of mammalian cells and have been widely used to probe the physiological function of the ubiquitin-proteasome pathway.

The CycLex Research Product Poly-Ubiquitinated Protein ELISA kit is designed to detect and quantify the level of total poly-ubiquitinated proteins in cell lysate. Since the amino acid sequence of ubiquitin is well conserved among mammals, this ELISA kit can be used for any mammalian cells. This assay is intended for the detection of poly-ubiquitinated proteins in cell lysate.

Microplate, 10X Wash Buffer, Cell Extraction Buffer, Dilution Buffer, Poly-Ubiquitinated Protein Standard, HRP conjugated Detection Antibody, Conjugate Dilution Buffer, Substrate Reagent, Stop Solution

Results exceeding polytoubiquitinated protein concentration of 100 units/mL, should be repeated with diluted samples

better than 1.182 units/ml of sample.

Ubiquitinated