PSMD13

PSMD13
Identifiers
Aliases	PSMD13, HSPC027, Rpn9, S11, p40.5, proteasome 26S subunit, non-ATPase 13
External IDs	MGI: 1345192 HomoloGene: 2110 GeneCards: PSMD13
Gene ontology Molecular function • structural molecule activity Cellular component • cytosol • membrane • proteasome accessory complex • proteasome regulatory particle • nucleoplasm • proteasome regulatory particle, lid subcomplex • proteasome complex • extracellular exosome • nucleus Biological process • regulation of cellular amino acid metabolic process • antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-dependent • ubiquitin-dependent protein catabolic process • regulation of mRNA stability • positive regulation of canonical Wnt signaling pathway • protein polyubiquitination • stimulatory C-type lectin receptor signaling pathway • tumor necrosis factor-mediated signaling pathway • MAPK cascade • Fc-epsilon receptor signaling pathway • NIK/NF-kappaB signaling • meiosis I • negative regulation of ubiquitin-protein ligase activity involved in mitotic cell cycle • anaphase-promoting complex-dependent catabolic process • T cell receptor signaling pathway • positive regulation of ubiquitin-protein ligase activity involved in regulation of mitotic cell cycle transition • negative regulation of canonical Wnt signaling pathway • proteasome assembly • Wnt signaling pathway, planar cell polarity pathway • proteasome-mediated ubiquitin-dependent protein catabolic process Sources:Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	5719	23997
Ensembl	ENSG00000185627	ENSMUSG00000025487
UniProt	Q9UNM6	Q9WVJ2
RefSeq (mRNA)	NM_002817 NM_175932	NM_011875
RefSeq (protein)	NP_002808.3 NP_787128.2	NP_036005.1
Location (UCSC)	Chr 11: 0.24 – 0.25 Mb	Chr 7: 140.88 – 140.9 Mb
PubMed search	[1]	[2]
Wikidata

26S proteasome non-ATPase regulatory subunit 13 is an enzyme that in humans is encoded by the PSMD13 gene.^[3][4]

Function

The 26S proteasome is a multicatalytic proteinase complex with a highly ordered structure composed of 2 complexes, a 20S core and a 19S regulator. The 20S core is composed of 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. The 19S regulator is composed of a base, which contains 6 ATPase subunits and 2 non-ATPase subunits, and a lid, which contains up to 10 non-ATPase subunits. Proteasomes are distributed throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An essential function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. This gene encodes a non-ATPase subunit of the 19S regulator. Two transcripts encoding different isoforms have been described.^[5]

Clinical significance

The Proteasome and its subunits are of clinical significance for at least two reasons: (1) a compromised complex assembly or a dysfunctional proteasome can be associated with the underlying pathophysiology of specific diseases, and (2) they can be exploited as drug targets for therapeutic interventions. More recently, more effort has been made to consider the proteasome for the development of novel diagnostic markers and strategies. An improved and comprehensive understanding of the pathophysiology of the proteasome should lead to clinical applications in the future.

The proteasomes form a pivotal component for the Ubiquitin-Proteasome System (UPS) ^[6] and corresponding cellular Protein Quality Control (PQC). Protein ubiquitination and subsequent proteolysis and degradation by the proteasome are important mechanisms in the regulation of the cell cycle, cell growth and differentiation, gene transcription, signal transduction and apoptosis.^[7] Subsequently, a compromised proteasome complex assembly and function lead to reduced proteolytic activities and the accumulation of damaged or misfolded protein species. Such protein accumulation may contribute to the pathogenesis and phenotypic characteristics in neurodegenerative diseases,^[8][9] cardiovascular diseases,^[10][11][12] inflammatory responses and autoimmune diseases,^[13] and systemic DNA damage responses leading to malignancies.^[14]

Several experimental and clinical studies have indicated that aberrations and deregulations of the UPS contribute to the pathogenesis of several neurodegenerative and myodegenerative disorders, including Alzheimer's disease,^[15] Parkinson's disease^[16] and Pick's disease,^[17] Amyotrophic lateral sclerosis (ALS),^[17] Huntington's disease,^[16] Creutzfeldt–Jakob disease,^[18] and motor neuron diseases, polyglutamine (PolyQ) diseases, Muscular dystrophies^[19] and several rare forms of neurodegenerative diseases associated with dementia.^[20] As part of the Ubiquitin-Proteasome System (UPS), the proteasome maintains cardiac protein homeostasis and thus plays a significant role in cardiac Ischemic injury,^[21] ventricular hypertrophy^[22] and Heart failure.^[23] Additionally, evidence is accumulating that the UPS plays an essential role in malignant transformation. UPS proteolysis plays a major role in responses of cancer cells to stimulatory signals that are critical for the development of cancer. Accordingly, gene expression by degradation of transcription factors, such as p53, c-Jun, c-Fos, NF-κB, c-Myc, HIF-1α, MATα2, STAT3, sterol-regulated element-binding proteins and androgen receptors are all controlled by the UPS and thus involved in the development of various malignancies.^[24] Moreover, the UPS regulates the degradation of tumor suppressor gene products such as adenomatous polyposis coli (APC) in colorectal cancer, retinoblastoma (Rb). and von Hippel-Lindau tumor suppressor (VHL), as well as a number of proto-oncogenes (Raf, Myc, Myb, Rel, Src, Mos, Abl). The UPS is also involved in the regulation of inflammatory responses. This activity is usually attributed to the role of proteasomes in the activation of NF-κB which further regulates the expression of pro inflammatory cytokines such as TNF-α, IL-β, IL-8, adhesion molecules (ICAM-1, VCAM-1, P selectine) and prostaglandins and nitric oxide (NO).^[13] Additionally, the UPS also plays a role in inflammatory responses as regulators of leukocyte proliferation, mainly through proteolysis of cyclines and the degradation of CDK inhibitors.^[25] Lastly, autoimmune disease patients with SLE, Sjogren's syndrome and rheumatoid arthritis (RA) predominantly exhibit circulating proteasomes which can be applied as clinical biomarkers.^[26]

Gene expression levels of the proteasomal subunits (PSMA1, PSMA5, PSMB4, PSMB5 and PSMD1) were investigated in 80 patients with neuroendocrine pulmonary tumors and compared to controls. The study reviled that PSMB4 mRNA was significantly associated with proliferative activity of neuroendocrine pulmonary tumors.^[27] However, a role of PSMA5 was also indicated in neuroendocrine pulmonary tumors. The PSMA5 protein has further been associated with the biosynthesis of conjugated linoleum acid (CLA) in mammary tissue.^[28]

Interactions

PSMD13 has been shown to interact with PSMC4^[29] and PSMD6.^[29]

References

Further reading