Alt. symbols: C13orf12 | HSPC014 | UMP1

Approved name: proteasome maturation protein
Alt. names: chromosome 13 open reading frame 12 | proteassemblin

Location: 13q12.3: 28659065 - 28678959 (+)
Gene type: protein_coding, 12 transcripts.

Scores: LoFtool: | pLI: 0.86142306 | LOEUF: 0.387

HGNC: 20330

NCBI: 51371, RefSeq: NG_027550.1

Ensembl: ENSG00000132963.9

LRG_ | Status: none

OMIM: 613386

Expression | ProteinAtlas

Proteasomes are multiprotein complexes with ATP-dependent proteolytic activities essential for intracellular clearance of K48 ubiquitin-tagged peptides and antigen processing to generate class I binding peptides. Proteasome maturation protein (POMP) serves as a chaperone for proteasome assembly, mediating 20S pre-proteasome association with the endoplasmic reticulum (ER) (PMID: 17948026). It is then degraded by the same proteasome upon completion of maturation. It mediates assembly. Immune cells contain a specialized immunoproteasome (i20S) that selectively incorporates specialized β1i (PSMB9/LMP2), β2i (PSMB10/LMP-10/MECL-1), and β5i (PSMB8/LMP7) catalytic subunits. During an immunological challenge, non-immune cells are stimulated by immune response products (IFN-γ or TNF-α), to upregulate i20S and enhance antigen presentation via class I major histocompatibility complex (MHC-I) molecules, allowing for the generation of an appropriate specific T cell response with subsequent T cell expansion and survival. POMP is upregulated by IFNs to enhance LMP7/PSMB8 catalytic subunit incorporation and accelerate i20S assembly (PMID: 29805043).

De novo heterozygous frameshift mutations in POMP escape nonsense-mediated decay (NMD) and result in dominant negative truncation mutants that cause POMP-related autoinflammation and immune dysregulation disease (PRAID) [OMIM: 618048, PRAAS2], characterized by severe neonatal-onset neutrophilic dermatosis, susceptibility to infections and autoimmunity. In contrast, a homozygous single base pair deletion in the 5′ untranslated region (UTR) of an alternative POMP transcript engenders a longe r-lived transcript that leads to an AR keratinization disorder of the skin with no inflammatory component called KLICK (keratosis linearis with ichthyosis congenita and sclerosing keratoderma) syndrome [OMIM: 601952] (PMID: 20226437). [Load More]