PROSITE documentation PDOC51917

Pru (pleckstrin-like receptor for the Ub) domain profile

In eukaryotes, selective protein degradation is performed primarily by the ubiquitin-proteasome pathway, in which substrate proteins are marked by covalently attached ubiquitin chains that mediate recognition by the proteasome. Rpn13 (also called ADRM1) is a subunit of the proteasome that serves as a receptor for both ubiquitin and Uch37, one of the proteasome's three deubiquitinating enzymes. Rpn13 binds ubiquitin though a conserved amino-terminal region termed the pleckstrin-like receptor for the Ub (Pru) domain (also known as the ubiquitin-binding domain, or UBD), which binds K48-linked diubiquitin. Its carboxy-terminal DEUBAD domain (see <PDOC51916>) binds deubiquinating enzyme Uch37/UCHL5 and enhances its isopeptidase activity [1,2,3].

The Pru domain forms two contiguous, antiparallel β-sheets with a configuration similar to the pleckstrin-homology structural domain: a four-stranded twisted antiparallel β-sheet (β 1, 4-6) packs almost orthogonally against a second triple stranded β-sheet (β 7-8). Juxtaposed to the three-stranded sheet are two β-strands (β 2-3). The Pru domain forms a hydrophobic core containing conserved hydrophobic residues, which are located within β-sheets. One end of the β-sandwich is capped by a long C-terminal amphipatic α-helix (see <PDB:2R2Y>) [1,2,3].

The profile we developed covers the entire Pru domain.