PSMA3

PSMA3
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 4R3O, 4R67, 5DSV, 5A0Q
Identifiers
Aliases	PSMA3, HC8, PSC3, proteasome subunit alpha 3
External IDs	MGI: 104883 HomoloGene: 2082 GeneCards: PSMA3
Gene ontology Molecular function • endopeptidase activity • peptidase activity • protein binding • threonine-type endopeptidase activity • hydrolase activity Cellular component • cytoplasm • cytosol • proteasome core complex, alpha-subunit complex • nucleoplasm • proteasome complex • extracellular exosome • nucleus • proteasome core complex Biological process • regulation of cellular amino acid metabolic process • antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-dependent • regulation of mRNA stability • ubiquitin-dependent protein catabolic process • positive regulation of canonical Wnt signaling pathway • protein polyubiquitination • stimulatory C-type lectin receptor signaling pathway • tumor necrosis factor-mediated signaling pathway • proteolysis • MAPK cascade • Fc-epsilon receptor signaling pathway • NIK/NF-kappaB signaling • negative regulation of ubiquitin-protein ligase activity involved in mitotic cell cycle • anaphase-promoting complex-dependent catabolic process • proteolysis involved in cellular protein 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 • regulation of endopeptidase activity • viral process • 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	5684	19167
Ensembl	ENSG00000100567	ENSMUSG00000060073
UniProt	P25788	O70435
RefSeq (mRNA)	NM_002788 NM_152132	NM_011184 NM_001310595 NM_001310596
RefSeq (protein)	NP_002779.1 NP_687033.1	NP_035314.3
Location (UCSC)	Chr 14: 58.24 – 58.27 Mb	Chr 12: 70.97 – 71 Mb
PubMed search	[1]	[2]
Wikidata

View/Edit Human

View/Edit Mouse

Proteasome subunit alpha type-3 also known as macropain subunit C8 and proteasome component C8 is a protein that in humans is encoded by the PSMA3 gene.^[3][4] This protein is one of the 17 essential subunits (alpha subunits 1-7, constitutive beta subunits 1-7, and inducible subunits including beta1i, beta2i, beta5i) that contributes to the complete assembly of 20S proteasome complex.

Function

The eukaryotic proteasome recognized degradable proteins, including damaged proteins for protein quality control purpose or key regulatory protein components for dynamic biological processes. An essential function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides. As a component of alpha ring, proteasome subunit alpha type-3 contributes to the formation of heptameric alpha rings and substrate entrance gate.

Structure

The human protein proteasome subunit alpha type-3 is 28 kDa in size and composed of 254 amino acids. The calculated theoretical pI of this protein is 5.19.

Complex assembly

The proteasome is a multicatalytic proteinase complex with a highly ordered 20S core structure. This barrel-shaped core structure is composed of 4 axially stacked rings of 28 non-identical subunits: the two end rings are each formed by 7 alpha subunits, and the two central rings are each formed by 7 beta subunits. Three beta subunits (beta1, beta2, and beta5) each contains a proteolytic active site and has distinct substrate preferences. Proteasomes are distributed throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway.^[5][6]

Mechanism

Crystal structures of isolated 20S proteasome complex demonstrate that the two rings of beta subunits form a proteolytic chamber and maintain all their active sites of proteolysis within the chamber.^[6] Concomitantly, the rings of alpha subunits form the entrance for substrates entering the proteolytic chamber. In an inactivated 20S proteasome complex, the gate into the internal proteolytic chamber are guarded by the N-terminal tails of specific alpha-subunit.^[7][8] The proteolytic capacity of 20S core particle (CP) can be activated when CP associates with one or two regulatory particles (RP) on one or both side of alpha rings. These regulatory particles include 19S proteasome complexes, 11S proteasome complex, etc. Following the CP-RP association, the confirmation of certain alpha subunits will change and consequently cause the opening of substrate entrance gate. Besides RPs, the 20S proteasomes can also be effectively activated by other mild chemical treatments, such as exposure to low levels of sodium dodecylsulfate (SDS) or NP-14.^[8][9]

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) ^[10] 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.^[11] 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,^[12][13] cardiovascular diseases,^[14][15][16] inflammatory responses and autoimmune diseases,^[17] and systemic DNA damage responses leading to malignancies.^[18]

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,^[19] Parkinson's disease^[20] and Pick's disease,^[21] Amyotrophic lateral sclerosis (ALS),^[21] Huntington's disease,^[20] Creutzfeldt–Jakob disease,^[22] and motor neuron diseases, polyglutamine (PolyQ) diseases, Muscular dystrophies^[23] and several rare forms of neurodegenerative diseases associated with dementia.^[24] As part of the Ubiquitin-Proteasome System (UPS), the proteasome maintains cardiac protein homeostasis and thus plays a significant role in cardiac Ischemic injury,^[25] ventricular hypertrophy^[26] and Heart failure.^[27] 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.^[28] 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).^[29] 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.^[30] Lastly, autoimmune disease patients with SLE, Sjogren's syndrome and rheumatoid arthritis (RA) predominantly exhibit circulating proteasomes which can be applied as clinical biomarkers.^[31]

A role of the proteasome subunit alpha type-3 has been linked in underlying mechanisms of human malignancies. It has been suggested that Cables1 as a novel p21 regulator through maintaining p21 stability and supporting the model that the tumor-suppressive function of Cables1 occurs at least in part through enhancing the tumor-suppressive activity of p21. In this process, Cables 1 mechanistically interferes the proteasome subunit alpha type-3 (PMSA3) hereby binding to p21 to induce cell death and inhibit cell proliferation.^[32]

Interactions

PSMA3 has been shown to interact with

• CRYAB,^[33]
• PLK1,^[34]
• PSMA6,^[35][36] and
• Zif268.^[37]

References

1. "Human PubMed Reference:".
2. "Mouse PubMed Reference:".
3. Tamura T, Lee DH, Osaka F, Fujiwara T, Shin S, Chung CH, Tanaka K, Ichihara A (Jun 1991). "Molecular cloning and sequence analysis of cDNAs for five major subunits of human proteasomes (multi-catalytic proteinase complexes)". Biochim Biophys Acta. 1089 (1): 95–102. doi:10.1016/0167-4781(91)90090-9. PMID 2025653.
4. Coux O, Tanaka K, Goldberg AL (Nov 1996). "Structure and functions of the 20S and 26S proteasomes". Annu Rev Biochem. 65: 801–47. doi:10.1146/annurev.bi.65.070196.004101. PMID 8811196.
5. Coux O, Tanaka K, Goldberg AL (1996). "Structure and functions of the 20S and 26S proteasomes". Annual Review of Biochemistry. 65: 801–47. doi:10.1146/annurev.bi.65.070196.004101. PMID 8811196.
6. Tomko RJ, Hochstrasser M (2013). "Molecular architecture and assembly of the eukaryotic proteasome". Annual Review of Biochemistry. 82: 415–45. doi:10.1146/annurev-biochem-060410-150257. PMC 3827779. PMID 23495936.
7. Groll M, Ditzel L, Löwe J, Stock D, Bochtler M, Bartunik HD, Huber R (Apr 1997). "Structure of 20S proteasome from yeast at 2.4 A resolution". Nature. 386 (6624): 463–71. Bibcode:1997Natur.386..463G. doi:10.1038/386463a0. PMID 9087403.
8. Groll M, Bajorek M, Köhler A, Moroder L, Rubin DM, Huber R, Glickman MH, Finley D (Nov 2000). "A gated channel into the proteasome core particle". Nature Structural Biology. 7 (11): 1062–7. doi:10.1038/80992. PMID 11062564.
9. Zong C, Gomes AV, Drews O, Li X, Young GW, Berhane B, Qiao X, French SW, Bardag-Gorce F, Ping P (Aug 2006). "Regulation of murine cardiac 20S proteasomes: role of associating partners". Circulation Research. 99 (4): 372–80. doi:10.1161/01.RES.0000237389.40000.02. PMID 16857963.
10. Kleiger G, Mayor T (Jun 2014). "Perilous journey: a tour of the ubiquitin-proteasome system". Trends in Cell Biology. 24 (6): 352–9. doi:10.1016/j.tcb.2013.12.003. PMC 4037451. PMID 24457024.
11. Goldberg, AL; Stein, R; Adams, J (August 1995). "New insights into proteasome function: from archaebacteria to drug development.". Chemistry & Biology. 2 (8): 503–8. doi:10.1016/1074-5521(95)90182-5. PMID 9383453.
12. Sulistio YA, Heese K (Jan 2015). "The Ubiquitin-Proteasome System and Molecular Chaperone Deregulation in Alzheimer's Disease". Molecular Neurobiology. doi:10.1007/s12035-014-9063-4. PMID 25561438.
13. Ortega Z, Lucas JJ (2014). "Ubiquitin-proteasome system involvement in Huntington's disease". Frontiers in Molecular Neuroscience. 7: 77. doi:10.3389/fnmol.2014.00077. PMC 4179678. PMID 25324717.
14. Sandri M, Robbins J (Jun 2014). "Proteotoxicity: an underappreciated pathology in cardiac disease". Journal of Molecular and Cellular Cardiology. 71: 3–10. doi:10.1016/j.yjmcc.2013.12.015. PMC 4011959. PMID 24380730.
15. Drews O, Taegtmeyer H (Dec 2014). "Targeting the ubiquitin-proteasome system in heart disease: the basis for new therapeutic strategies". Antioxidants & Redox Signaling. 21 (17): 2322–43. doi:10.1089/ars.2013.5823. PMC 4241867. PMID 25133688.
16. Wang ZV, Hill JA (Feb 2015). "Protein quality control and metabolism: bidirectional control in the heart". Cell Metabolism. 21 (2): 215–26. doi:10.1016/j.cmet.2015.01.016. PMC 4317573. PMID 25651176.
17. Karin, M; Delhase, M (2000). "The I kappa B kinase (IKK) and NF-kappa B: Key elements of proinflammatory signalling". Seminars in Immunology. 12 (1): 85–98. doi:10.1006/smim.2000.0210. PMID 10723801.
18. Ermolaeva MA, Dakhovnik A, Schumacher B (Jan 2015). "Quality control mechanisms in cellular and systemic DNA damage responses". Ageing Research Reviews. 23 (Pt A): 3–11. doi:10.1016/j.arr.2014.12.009. PMID 25560147.
19. Checler, F; da Costa, CA; Ancolio, K; Chevallier, N; Lopez-Perez, E; Marambaud, P (26 July 2000). "Role of the proteasome in Alzheimer's disease.". Biochimica et Biophysica Acta. 1502 (1): 133–8. doi:10.1016/s0925-4439(00)00039-9. PMID 10899438.
20. Chung, KK; Dawson, VL; Dawson, TM (November 2001). "The role of the ubiquitin-proteasomal pathway in Parkinson's disease and other neurodegenerative disorders.". Trends in Neurosciences. 24 (11 Suppl): S7–14. doi:10.1016/s0166-2236(00)01998-6. PMID 11881748.
21. Ikeda, K; Akiyama, H; Arai, T; Ueno, H; Tsuchiya, K; Kosaka, K (July 2002). "Morphometrical reappraisal of motor neuron system of Pick's disease and amyotrophic lateral sclerosis with dementia.". Acta Neuropathologica. 104 (1): 21–8. doi:10.1007/s00401-001-0513-5. PMID 12070660.
22. Manaka, H; Kato, T; Kurita, K; Katagiri, T; Shikama, Y; Kujirai, K; Kawanami, T; Suzuki, Y; Nihei, K; Sasaki, H (11 May 1992). "Marked increase in cerebrospinal fluid ubiquitin in Creutzfeldt–Jakob disease.". Neuroscience Letters. 139 (1): 47–9. doi:10.1016/0304-3940(92)90854-z. PMID 1328965.
23. Mathews, KD; Moore, SA (January 2003). "Limb-girdle muscular dystrophy.". Current neurology and neuroscience reports. 3 (1): 78–85. doi:10.1007/s11910-003-0042-9. PMID 12507416.
24. Mayer, RJ (March 2003). "From neurodegeneration to neurohomeostasis: the role of ubiquitin.". Drug news & perspectives. 16 (2): 103–8. doi:10.1358/dnp.2003.16.2.829327. PMID 12792671.
25. Calise, J; Powell, S. R. (2013). "The ubiquitin proteasome system and myocardial ischemia". AJP: Heart and Circulatory Physiology. 304 (3): H337–49. doi:10.1152/ajpheart.00604.2012. PMC 3774499. PMID 23220331.
26. Predmore, JM; Wang, P; Davis, F; Bartolone, S; Westfall, MV; Dyke, DB; Pagani, F; Powell, SR; Day, SM (2 March 2010). "Ubiquitin proteasome dysfunction in human hypertrophic and dilated cardiomyopathies.". Circulation. 121 (8): 997–1004. doi:10.1161/circulationaha.109.904557. PMC 2857348. PMID 20159828.
27. Powell, SR (July 2006). "The ubiquitin-proteasome system in cardiac physiology and pathology". American Journal of Physiology. Heart and Circulatory Physiology. 291 (1): H1–H19. doi:10.1152/ajpheart.00062.2006. PMID 16501026.
28. Adams, J (1 April 2003). "Potential for proteasome inhibition in the treatment of cancer.". Drug Discovery Today. 8 (7): 307–15. doi:10.1016/s1359-6446(03)02647-3. PMID 12654543.
29. Karin, M; Delhase, M (February 2000). "The I kappa B kinase (IKK) and NF-kappa B: key elements of proinflammatory signalling.". Seminars in immunology. 12 (1): 85–98. doi:10.1006/smim.2000.0210. PMID 10723801.
30. Ben-Neriah, Y (January 2002). "Regulatory functions of ubiquitination in the immune system". Nature Immunology. 3 (1): 20–6. doi:10.1038/ni0102-20. PMID 11753406.
31. Egerer, K; Kuckelkorn, U; Rudolph, PE; Rückert, JC; Dörner, T; Burmester, GR; Kloetzel, PM; Feist, E (October 2002). "Circulating proteasomes are markers of cell damage and immunologic activity in autoimmune diseases.". The Journal of rheumatology. 29 (10): 2045–52. PMID 12375310.
32. Shi, Z; Li, Z; Li, ZJ; Cheng, K; Du, Y; Fu, H; Khuri, FR (7 May 2015). "Cables1 controls p21/Cip1 protein stability by antagonizing proteasome subunit alpha type 3.". Oncogene. 34 (19): 2538–45. doi:10.1038/onc.2014.171. PMID 24975575.
33. Boelens WC, Croes Y, de Jong WW (Jan 2001). "Interaction between alphaB-crystallin and the human 20S proteasomal subunit C8/alpha7". Biochim. Biophys. Acta. 1544 (1–2): 311–9. doi:10.1016/S0167-4838(00)00243-0. PMID 11341940.
34. Feng Y, Longo DL, Ferris DK (Jan 2001). "Polo-like kinase interacts with proteasomes and regulates their activity". Cell Growth Differ. 12 (1): 29–37. PMID 11205743.
35. Stelzl U, Worm U, Lalowski M, Haenig C, Brembeck FH, Goehler H, Stroedicke M, Zenkner M, Schoenherr A, Koeppen S, Timm J, Mintzlaff S, Abraham C, Bock N, Kietzmann S, Goedde A, Toksöz E, Droege A, Krobitsch S, Korn B, Birchmeier W, Lehrach H, Wanker EE (Sep 2005). "A human protein-protein interaction network: a resource for annotating the proteome". Cell. 122 (6): 957–68. doi:10.1016/j.cell.2005.08.029. PMID 16169070.
36. Gerards WL, de Jong WW, Bloemendal H, Boelens W (Jan 1998). "The human proteasomal subunit HsC8 induces ring formation of other alpha-type subunits". J. Mol. Biol. 275 (1): 113–21. doi:10.1006/jmbi.1997.1429. PMID 9451443.
37. Bae MH, Jeong CH, Kim SH, Bae MK, Jeong JW, Ahn MY, Bae SK, Kim ND, Kim CW, Kim KR, Kim KW (Oct 2002). "Regulation of Egr-1 by association with the proteasome component C8". Biochim. Biophys. Acta. 1592 (2): 163–7. doi:10.1016/S0167-4889(02)00310-5. PMID 12379479.

Further reading

• Goff SP (2003). "Death by deamination: a novel host restriction system for HIV-1". Cell. 114 (3): 281–3. doi:10.1016/S0092-8674(03)00602-0. PMID 12914693.
• Kristensen P, Johnsen AH, Uerkvitz W, Tanaka K, Hendil KB (1995). "Human proteasome subunits from 2-dimensional gels identified by partial sequencing". Biochem. Biophys. Res. Commun. 205 (3): 1785–9. doi:10.1006/bbrc.1994.2876. PMID 7811265.
• Akioka H, Forsberg NE, Ishida N, Okumura K, Nogami M, Taguchi H, Noda C, Tanaka K (1995). "Isolation and characterization of the HC8 subunit gene of the human proteasome". Biochem. Biophys. Res. Commun. 207 (1): 318–23. doi:10.1006/bbrc.1995.1190. PMID 7857283.
• Castaño JG, Mahillo E, Arizti P, Arribas J (1996). "Phosphorylation of C8 and C9 subunits of the multicatalytic proteinase by casein kinase II and identification of the C8 phosphorylation sites by direct mutagenesis". Biochemistry. 35 (12): 3782–9. doi:10.1021/bi952540s. PMID 8619999.
• Seeger M, Ferrell K, Frank R, Dubiel W (1997). "HIV-1 tat inhibits the 20 S proteasome and its 11 S regulator-mediated activation". J. Biol. Chem. 272 (13): 8145–8. doi:10.1074/jbc.272.13.8145. PMID 9079628.
• Gerards WL, de Jong WW, Bloemendal H, Boelens W (1998). "The human proteasomal subunit HsC8 induces ring formation of other alpha-type subunits". J. Mol. Biol. 275 (1): 113–21. doi:10.1006/jmbi.1997.1429. PMID 9451443.
• Madani N, Kabat D (1998). "An Endogenous Inhibitor of Human Immunodeficiency Virus in Human Lymphocytes Is Overcome by the Viral Vif Protein". J. Virol. 72 (12): 10251–5. PMC 110608. PMID 9811770.
• Simon JH, Gaddis NC, Fouchier RA, Malim MH (1998). "Evidence for a newly discovered cellular anti-HIV-1 phenotype". Nat. Med. 4 (12): 1397–400. doi:10.1038/3987. PMID 9846577.
• Mulder LC, Muesing MA (2000). "Degradation of HIV-1 integrase by the N-end rule pathway". J. Biol. Chem. 275 (38): 29749–53. doi:10.1074/jbc.M004670200. PMID 10893419.
• Connell P, Ballinger CA, Jiang J, Wu Y, Thompson LJ, Höhfeld J, Patterson C (2001). "The co-chaperone CHIP regulates protein triage decisions mediated by heat-shock proteins". Nat. Cell Biol. 3 (1): 93–6. doi:10.1038/35050618. PMID 11146632.
• Feng Y, Longo DL, Ferris DK (2001). "Polo-like kinase interacts with proteasomes and regulates their activity". Cell Growth Differ. 12 (1): 29–37. PMID 11205743.
• Boelens WC, Croes Y, de Jong WW (2001). "Interaction between alphaB-crystallin and the human 20S proteasomal subunit C8/alpha7". Biochim. Biophys. Acta. 1544 (1–2): 311–9. doi:10.1016/S0167-4838(00)00243-0. PMID 11341940.
• Touitou R, Richardson J, Bose S, Nakanishi M, Rivett J, Allday MJ (2001). "A degradation signal located in the C-terminus of p21WAF1/CIP1 is a binding site for the C8 α-subunit of the 20S proteasome". EMBO J. 20 (10): 2367–75. doi:10.1093/emboj/20.10.2367. PMC 125454. PMID 11350925.
• Sheehy AM, Gaddis NC, Choi JD, Malim MH (2002). "Isolation of a human gene that inhibits HIV-1 infection and is suppressed by the viral Vif protein". Nature. 418 (6898): 646–50. Bibcode:2002Natur.418..646S. doi:10.1038/nature00939. PMID 12167863.
• Claverol S, Burlet-Schiltz O, Girbal-Neuhauser E, Gairin JE, Monsarrat B (2003). "Mapping and structural dissection of human 20 S proteasome using proteomic approaches". Mol. Cell Proteomics. 1 (8): 567–78. doi:10.1074/mcp.M200030-MCP200. PMID 12376572.
• Bae MH, Jeong CH, Kim SH, Bae MK, Jeong JW, Ahn MY, Bae SK, Kim ND, Kim CW, Kim KR, Kim KW (2003). "Regulation of Egr-1 by association with the proteasome component C8". Biochim. Biophys. Acta. 1592 (2): 163–7. doi:10.1016/S0167-4889(02)00310-5. PMID 12379479.
• Huang X, Seifert U, Salzmann U, Henklein P, Preissner R, Henke W, Sijts AJ, Kloetzel PM, Dubiel W (2002). "The RTP site shared by the HIV-1 Tat protein and the 11S regulator subunit alpha is crucial for their effects on proteasome function including antigen processing". J. Mol. Biol. 323 (4): 771–82. doi:10.1016/S0022-2836(02)00998-1. PMID 12419264.