Homologous Superfamily

Proteasome activator PA28, C-terminal domain superfamily (IPR036997)

Short name: PA28_C_sf

Overlapping entries


The specificity of the 20S proteasome, which degrades many intracellular proteins, is regulated by protein complexes that bind to one or both ends of the cylindrical proteasome structure. Proteasome activator 28 (PA28), also known as 11S regulator or REG, is one of these complexes. PA28 binds to the 20S proteasome and stimulates peptidase activity in and ATP-independent manner.

Three PA28 subunits that have been identified, PA28alpha, PA28beta and PA28gamma (also known as the Ki antigen), which share extensive sequence similarity, apart from a highly variable internal segment [PMID: 9403698]. PA28alpha and PA28beta form a ring shaped hexameric structure of alternating alpha and beta subunits. The catalytic properties of PA28alpha and PA28beta-activated proteosome are similar [PMID: 11147828, PMID: 9346951].

This entry represents the C-terminal domain superfamily found in the proteasome activator 28 subunits.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

No terms assigned in this category.

Cellular Component

GO:0008537 proteasome activator complex

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.