Material Data Sheet

PA28 Activator alpha subunit

Price: $199.00
Catalog #: E-380

PA28 Activator alpha subunit

100 µg
Data Sheet: 

PA28 is a ring-shaped 11S multimeric complex that can bind to the two ends of the 20S proteasome and dramatically stimulates its capacity to hydrolyze small peptides (but not ubiquitinated proteins or large substrates). It functions in immuno-proteasome assembly, is required for antigen processing, and enhances the generation of class I peptides. In mammals, PA28 is composed of two homologous subunits; PA28α and PA28β, both of which are interferon-induced. In vitro, PA28α forms a heptameric ring that can stimulate peptide hydrolysis by 20S particles to the same extent as the heteromeric (3α3β) complex. This protein has been purified from E.coli.

Product Information

X mg/ml (X μM) in 50 mM Hepes pH 8.0, 200 mM NaCl, 1mM DTT
29 kDa (monomeric weight)
> 95% by SDS-PAGE under reducing conditions and visualized by Colloidal Coomassie Blue stain

Use & Storage

Recombinant Human PA28 Activator α Subunit is ideal for the activation of latent 20S Proteasome complexes. Reaction conditions will need to be optimized for each specific application. Initially, we recommend a 5-­15 ­fold molar excess of PA28α relative to 20S Proteasome.

Store at -80°C. Avoid multiple freeze/thaw cycles.



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