homocysteine-responsive endoplasmic reticulum-resident ubiquitin-like domain member 1 protein; methyl methanesulfonate (MMF)-inducible fragment protein 1 (HERPUD1, HERP, KIAA0025, MIF1)

Function

• component of the endoplasmic reticulum quality control (ERQC) system also called ER-associated degradation (ERAD)
• role in ubiquitin-dependent degradation of misfolded endoplasmic reticulum proteins
• could enhance presenilin-mediated beta-amyloid protein-40 (A4/40) generation
• interacts with PSEN1 & PSEN2
• interacts with SYVN1 & UBXN6

Structure

contains 1 ubiquitin-like domain

Compartment

• endoplasmic reticulum membrane; single-pass membrane protein
• although the precise topology is not known, experimental data suggest that both the N- & C-termini face the cytosol

Alternative splicing

named isoforms=3

Expression

• widely expressed
• in the brain, expression seems to be restricted to neurons & vascular smooth muscle cells

Pathology

• present in activated microglia in senile plaques in the brain of patients with Alzheimer disease

More general terms

• membrane protein

Additional terms

• ubiquitin (UBCEP2, UBB, UBC)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=9709
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:9709
• OMIM: https://mirror.omim.org/entry/608070
• UniProt: http://www.uniprot.org/uniprot/Q15011.html