Material Data Sheet

PA28 Activator alpha subunit

Price: $199.00
Catalog #: E-381

PA28 Activator alpha subunit

100 µg
Data Sheet: 
The Proteasome Activator 28 (PA28) Regulatory Complex, also known as the 11S Regulatory (REG) Complex, is a ring­shaped, multimeric, ATP­independent regulatory complex that can bind to one or both ends of the 20S Proteasome or 20S Immunoproteasome. The PA28 Regulatory Complex stimulates the proteasome to hydrolyze small peptides, but not ubiquitinated proteins, for the production of peptides for MHC class I antigen presentation. Three PA28 Regulatory Complex subunits, alpha, beta, and gamma, have been identified and can oligomerize to form the PA28 Regulatory Complex. While the expression of the PA28 alpha and beta subunits are induced by IFN­gamma, the PA28 gamma subunit is not significantly affected. The human PA28 Activator alpha Subunit, also known as 11S REG alpha, is a 249 amino acid (aa) member of the PA28 family of regulatory proteins with a predicted molecular weight of 29 kDa. The mouse and rat orthologs share 94% and 95% aa sequence identity with the human protein, respectively. In vivo, PA28 alpha forms hetero­heptamers or ­hexamers with PA28 beta. PA28 alpha can also form active homo­heptamers in vitro and can be used to activate the 20S Proteasome. In addition to regulating production of MHC class I antigens, PA28 alpha may protect against oxidative stress. This protein has been functionally tested using human 20S proteasome.

Product Information

50 mM Hepes pH 8.0, 200 mM NaCl, 1 mM DTT
29 kDa (monomeric weight)

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



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