Proteasome component (PCI) domain (IPR000717)

Short name: PCI_dom

Overlapping homologous superfamilies


Domain relationships



A homology domain of unclear function, occurs in the C-terminal region of several regulatory components of the 26S proteasome as well as in other proteins. This domain has also been called the PINT motif (Proteasome, Int-6, Nip-1 and TRIP-15) [PMID: 9644972]. Apparently, all of the characterised proteins containing PCI domains are parts of larger multi-protein complexes. Proteins with PCI domains include budding yeast proteasome regulatory components Rpn3(Sun2), Rpn5, Rpn6, Rpn7and Rpn9 [PMID: 9584156]; mammalian proteasome regulatory components p55, p58 and p44.5, and translation initiation factor 3 complex subunits p110 and INT6 [PMID: 8995409, PMID: 9341143]; Arabidopsis COP9 and FUS6/COP11 [PMID: 8689678]; mammalian G-protein pathway suppressor GPS1, and several uncharacterised ORFs from plant, nematodes and mammals. The complete homology domain comprises approx. 200 residues, the highest conservation is found in the C-terminal half. Several of the proteins mentioned above have no detectable homology to the N-terminal half of the domain.

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005515 protein binding

Cellular Component

No terms assigned in this category.

Contributing signatures

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