P4HB

Prolyl 4-hydroxylase, beta polypeptide
PDB rendering based on 1bjx.
Available structures PDB 1BJX, 1MEK, 1X5C, 2BJX, 2K18, 3BJ5
Identifiers
Symbols	P4HB; DSI; ERBA2L; GIT; P4Hbeta; PDI; PDIA1; PHDB; PO4DB; PO4HB; PROHB
External IDs	OMIM: 176790 MGI: 97464 HomoloGene: 55495 GeneCards: P4HB Gene
EC number	5.3.4.1
Gene Ontology Molecular function • protein disulfide isomerase activity • procollagen-proline 4-dioxygenase activity • protein binding • electron carrier activity • protein disulfide oxidoreductase activity • isomerase activity • protein heterodimerization activity Cellular component • extracellular region • endoplasmic reticulum • endoplasmic reticulum lumen • microsome • ER-Golgi intermediate compartment • plasma membrane • cell surface • melanosome Biological process • lipid metabolic process • glycerol ether metabolic process • peptidyl-proline hydroxylation to 4-hydroxy-L-proline • lipoprotein metabolic process • cell redox homeostasis Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	5034	18453
Ensembl	ENSG00000185624	ENSMUSG00000025130
UniProt	P07237	Q3TF72
RefSeq (mRNA)	NM_000918	NM_011032.2
RefSeq (protein)	NP_000909	NP_035162.1
Location (UCSC)	Chr 17: 79.8 – 79.82 Mb	Chr 11: 120.42 – 120.43 Mb
PubMed search	[1]	[2]

Protein disulfide-isomerase is an enzyme that in humans is encoded by the P4HB gene.^[1][2]

This gene encodes the beta subunit of prolyl 4-hydroxylase, a highly abundant multifunctional enzyme that belongs to the protein disulfide isomerase family. When present as a tetramer consisting of two alpha and two beta subunits, this enzyme is involved in hydroxylation of prolyl residues in preprocollagen. This enzyme is also a disulfide isomerase containing two thioredoxin domains that catalyze the formation, breakage and rearrangement of disulfide bonds. Other known functions include its ability to act as a chaperone that inhibits aggregation of misfolded proteins in a concentration-dependent manner, its ability to bind thyroid hormone, its role in both the influx and efflux of S-nitrosothiol-bound nitric oxide, and its function as a subunit of the microsomal triglyceride transfer protein complex.^[2]

Interactions

P4HB has been shown to interact with UBQLN1,^[3] ERO1LB^[4][5] and ERO1L.^[4][5]

References

1. ^ Shoulders CC, Brett DJ, Bayliss JD, Narcisi TM, Jarmuz A, Grantham TT, Leoni PR, Bhattacharya S, Pease RJ, Cullen PM, et al. (Mar 1994). "Abetalipoproteinemia is caused by defects of the gene encoding the 97 kDa subunit of a microsomal triglyceride transfer protein". Hum Mol Genet 2 (12): 2109–16. doi:10.1093/hmg/2.12.2109. PMID 8111381. 
2. ^ ^{a b} "Entrez Gene: P4HB procollagen-proline, 2-oxoglutarate 4-dioxygenase (proline 4-hydroxylase), beta polypeptide". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=5034. 
3. ^ Ko, Han Seok; Uehara Takashi, Nomura Yasuyuki (Sep. 2002). "Role of ubiquilin associated with protein-disulfide isomerase in the endoplasmic reticulum in stress-induced apoptotic cell death". J. Biol. Chem. (United States) 277 (38): 35386–92. doi:10.1074/jbc.M203412200. ISSN 0021-9258. PMID 12095988. 
4. ^ ^{a b} Anelli, Tiziana; Alessio Massimo, Mezghrani Alexandre, Simmen Thomas, Talamo Fabio, Bachi Angela, Sitia Roberto (Feb. 2002). "ERp44, a novel endoplasmic reticulum folding assistant of the thioredoxin family". EMBO J. (England) 21 (4): 835–44. doi:10.1093/emboj/21.4.835. ISSN 0261-4189. PMC 125352. PMID 11847130. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=125352. 
5. ^ ^{a b} Mezghrani, A; Fassio A, Benham A, Simmen T, Braakman I, Sitia R (Nov. 2001). "Manipulation of oxidative protein folding and PDI redox state in mammalian cells". EMBO J. (England) 20 (22): 6288–96. doi:10.1093/emboj/20.22.6288. ISSN 0261-4189. PMC 125306. PMID 11707400. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=125306. 

Further reading

• Pihlajaniemi T, Myllylä R, Kivirikko KI (1992). "Prolyl 4-hydroxylase and its role in collagen synthesis". J. Hepatol. 13 Suppl 3: S2–7. doi:10.1016/0168-8278(91)90002-S. PMID 1667665. 
• Wilkinson B, Gilbert HF (2004). "Protein disulfide isomerase". Biochim. Biophys. Acta 1699 (1–2): 35–44. doi:10.1016/j.bbapap.2004.02.017. PMID 15158710. 
• Hochstrasser DF, Frutiger S, Paquet N, et al. (1993). "Human liver protein map: a reference database established by microsequencing and gel comparison". Electrophoresis 13 (12): 992–1001. doi:10.1002/elps.11501301201. PMID 1286669. 
• Chessler SD, Byers PH (1992). "Defective folding and stable association with protein disulfide isomerase/prolyl hydroxylase of type I procollagen with a deletion in the pro alpha 2(I) chain that preserves the Gly-X-Y repeat pattern". J. Biol. Chem. 267 (11): 7751–7. PMID 1339453. 
• Vuori K, Myllylä R, Pihlajaniemi T, Kivirikko KI (1992). "Expression and site-directed mutagenesis of human protein disulfide isomerase in Escherichia coli. This multifunctional polypeptide has two independently acting catalytic sites for the isomerase activity". J. Biol. Chem. 267 (11): 7211–4. PMID 1559965. 
• Tasanen K, Oikarinen J, Kivirikko KI, Pihlajaniemi T (1992). "Promoter of the gene for the multifunctional protein disulfide isomerase polypeptide. Functional significance of the six CCAAT boxes and other promoter elements". J. Biol. Chem. 267 (16): 11513–9. PMID 1597478. 
• Bauw G, Rasmussen HH, van den Bulcke M, et al. (1990). "Two-dimensional gel electrophoresis, protein electroblotting and microsequencing: a direct link between proteins and genes". Electrophoresis 11 (7): 528–36. doi:10.1002/elps.1150110703. PMID 1699755. 
• Ward LD, Hong J, Whitehead RH, Simpson RJ (1991). "Development of a database of amino acid sequences for human colon carcinoma proteins separated by two-dimensional polyacrylamide gel electrophoresis". Electrophoresis 11 (10): 883–91. doi:10.1002/elps.1150111019. PMID 2079031. 
• Tasanen K, Parkkonen T, Chow LT, et al. (1988). "Characterization of the human gene for a polypeptide that acts both as the beta subunit of prolyl 4-hydroxylase and as protein disulfide isomerase". J. Biol. Chem. 263 (31): 16218–24. PMID 2846539. 
• Koivu J, Myllylä R, Helaakoski T, et al. (1987). "A single polypeptide acts both as the beta subunit of prolyl 4-hydroxylase and as a protein disulfide-isomerase". J. Biol. Chem. 262 (14): 6447–9. PMID 3032969. 
• Pihlajaniemi T, Helaakoski T, Tasanen K, et al. (1987). "Molecular cloning of the beta-subunit of human prolyl 4-hydroxylase. This subunit and protein disulphide isomerase are products of the same gene". EMBO J. 6 (3): 643–9. PMC 553446. PMID 3034602. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=553446. 
• Morris JI, Varandani PT (1988). "Characterization of a cDNA for human glutathione-insulin transhydrogenase (protein-disulfide isomerase/oxidoreductase)". Biochim. Biophys. Acta 949 (2): 169–80. PMID 3342239. 
• Gosden JR, Middleton PG, Rout D, De Angelis C (1987). "Chromosomal localization of the human oncogene ERBA2". Cytogenet. Cell Genet. 43 (3–4): 150–3. doi:10.1159/000132313. PMID 3467900. 
• Cheng SY, Gong QH, Parkison C, et al. (1987). "The nucleotide sequence of a human cellular thyroid hormone binding protein present in endoplasmic reticulum". J. Biol. Chem. 262 (23): 11221–7. PMID 3611107. 
• Helaakoski T, Annunen P, Vuori K, et al. (1995). "Cloning, baculovirus expression, and characterization of a second mouse prolyl 4-hydroxylase alpha-subunit isoform: formation of an alpha 2 beta 2 tetramer with the protein disulfide-isomerase/beta subunit". Proc. Natl. Acad. Sci. U.S.A. 92 (10): 4427–31. doi:10.1073/pnas.92.10.4427. PMC 41957. PMID 7753822. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=41957. 
• Kemmink J, Darby NJ, Dijkstra K, et al. (1996). "Nuclear magnetic resonance characterization of the N-terminal thioredoxin-like domain of protein disulfide isomerase". Protein Sci. 4 (12): 2587–93. doi:10.1002/pro.5560041216. PMC 2143042. PMID 8580850. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2143042. 
• Kemmink J, Darby NJ, Dijkstra K, et al. (1996). "Structure determination of the N-terminal thioredoxin-like domain of protein disulfide isomerase using multidimensional heteronuclear 13C/15N NMR spectroscopy". Biochemistry 35 (24): 7684–91. doi:10.1021/bi960335m. PMID 8672469. 
• Ji H, Reid GE, Moritz RL, et al. (1997). "A two-dimensional gel database of human colon carcinoma proteins". Electrophoresis 18 (3–4): 605–13. doi:10.1002/elps.1150180344. PMID 9150948.