T-complex 1 explained

In humans, the gene T-complex 1, a.k.a. TCP1, encodes the protein TCP-1, a.k.a. T-complex protein 1 subunit alpha.^{[1] [2] [3]}

Function

This gene encodes a molecular chaperone that is a member of the TRiC complex. This complex consists of two identical stacked rings, each containing eight different proteins. Unfolded polypeptides enter the central cavity of the complex and are folded in an ATP-dependent manner. The complex folds various proteins, including actin and tubulin. Alternate transcriptional splice variants of this gene, encoding different isoforms, have been characterized.^[3]

Interactions

T-complex 1 has been shown to interact with PPP4C^{[4] [5]} and HDAC3.^[6] CCT also directly interacts with lectin type oxidized LDL receptor-1 (LOX-1) while its ligand oxidized low density lipoprotein (OxLDL) disassociates CCT from LOX-1.^[7]

Further reading

• Horwich AL, Willison KR . Protein folding in the cell: functions of two families of molecular chaperone, hsp 60 and TF55-TCP1 . Philos. Trans. R. Soc. Lond. B Biol. Sci. . 339 . 1289 . 313–25; discussion 325–6 . 1993 . 8098536 . 10.1098/rstb.1993.0030.
• Burston SG, Clarke AR . Molecular chaperones: physical and mechanistic properties . Essays Biochem. . 29 . 125–36 . 1997 . 9189717.
• Blanché H, Wright LG, Vergnaud G, de Gouyon B, Lauthier V, Silver LM, Dausset J, Cann HM, Spielman RS . Genetic mapping of three human homologues of murine t-complex genes localizes TCP10 to 6q27, 15 cM distal to TCP1 and PLG . Genomics . 12 . 4 . 826–8 . 1992 . 1572657 . 10.1016/0888-7543(92)90317-L.
• Dawson SJ, White LA . Treatment of Haemophilus aphrophilus endocarditis with ciprofloxacin . J. Infect. . 24 . 3 . 317–20 . 1992 . 1602151 . 10.1016/S0163-4453(05)80037-4.
• Yaffe MB, Farr GW, Miklos D, Horwich AL, Sternlicht ML, Sternlicht H . TCP1 complex is a molecular chaperone in tubulin biogenesis . Nature . 358 . 6383 . 245–8 . 1992 . 1630491 . 1992Natur.358..245Y . 4287521 . 10.1038/358245a0.
• Lewis VA, Hynes GM, Zheng D, Saibil H, Willison K . T-complex polypeptide-1 is a subunit of a heteromeric particle in the eukaryotic cytosol . Nature . 358 . 6383 . 249–52 . 1992 . 1630492 . 1992Natur.358..249L . 4306360 . 10.1038/358249a0.
• Ursic D, Culbertson MR . The yeast homolog to mouse Tcp-1 affects microtubule-mediated processes . Mol. Cell. Biol. . 11 . 5 . 2629–40 . 1991 . 1901944 . 360032 . 10.1128/mcb.11.5.2629.
• Kirchhoff C, Willison K . Nucleotide and amino-acid sequence of human testis-derived TCP1 . Nucleic Acids Res. . 18 . 14 . 4247 . 1990 . 2377466 . 331189 . 10.1093/nar/18.14.4247.
• Roobol A, Holmes FE, Hayes NV, Baines AJ, Carden MJ . Cytoplasmic chaperonin complexes enter neurites developing in vitro and differ in subunit composition within single cells . J. Cell Sci. . 108 . 4 . 1477–88 . 1995 . 7615668 . 10.1242/jcs.108.4.1477.
• Ashworth A . Two acetyl-CoA acetyltransferase genes located in the t-complex region of mouse chromosome 17 partially overlap the Tcp-1 and Tcp-1x genes . Genomics . 18 . 2 . 195–8 . 1994 . 7904580 . 10.1006/geno.1993.1454.
• Miklos D, Caplan S, Mertens D, Hynes G, Pitluk Z, Kashi Y, Harrison-Lavoie K, Stevenson S, Brown C, Barrell B . Primary structure and function of a second essential member of the heterooligomeric TCP1 chaperonin complex of yeast, TCP1 beta . Proc. Natl. Acad. Sci. U.S.A. . 91 . 7 . 2743–7 . 1994 . 7908441 . 43446 . 1994PNAS...91.2743M . 10.1073/pnas.91.7.2743 . free.
• Chen X, Sullivan DS, Huffaker TC . Two yeast genes with similarity to TCP-1 are required for microtubule and actin function in vivo . Proc. Natl. Acad. Sci. U.S.A. . 91 . 19 . 9111–5 . 1994 . 7916460 . 44757 . 1994PNAS...91.9111C . 10.1073/pnas.91.19.9111 . free.
• Kubota H, Hynes G, Carne A, Ashworth A, Willison K . Identification of six Tcp-1-related genes encoding divergent subunits of the TCP-1-containing chaperonin . Curr. Biol. . 4 . 2 . 89–99 . 1994 . 7953530 . 31300131 . 10.1016/S0960-9822(94)00024-2.
• Frydman J, Hartl FU . Principles of chaperone-assisted protein folding: differences between in vitro and in vivo mechanisms . Science . 272 . 5267 . 1497–502 . 1996 . 8633246 . 1996Sci...272.1497F . 22363826 . 10.1126/science.272.5267.1497.
• Moudjou M, Bordes N, Paintrand M, Bornens M . gamma-Tubulin in mammalian cells: the centrosomal and the cytosolic forms . J. Cell Sci. . 109 . 4 . 875–87 . 1996 . 8718679 . 10.1242/jcs.109.4.875.
• Morrison K, Papapetrou C, Attwood J, Hol F, Lynch SA, Sampath A, Hamel B, Burn J, Sowden J, Stott D, Mariman E, Edwards YH . Genetic mapping of the human homologue (T) of mouse T(Brachyury) and a search for allele association between human T and spina bifida . Hum. Mol. Genet. . 5 . 5 . 669–74 . 1997 . 8733136 . 2066/23945 . free . 10.1093/hmg/5.5.669 . free.
• Masuno M, Fukao T, Song XQ, Yamaguchi S, Orii T, Kondo N, Imaizumi K, Kuroki Y . Assignment of the human cytosolic acetoacetyl-coenzyme A thiolase (ACAT2) gene to chromosome 6q25.3-q26 . Genomics . 36 . 1 . 217–8 . 1997 . 8812443 . 10.1006/geno.1996.0452.

Notes and References

1. Fonatsch C, Gradl G, Ragoussis J, Ziegler A . Assignment of the TCP1 locus to the long arm of human chromosome 6 by in situ hybridization . Cytogenet Cell Genet . 45 . 2 . 109–12 . Oct 1987 . 3476253 . 10.1159/000132439.
2. Willison K, Kelly A, Dudley K, Goodfellow P, Spurr N, Groves V, Gorman P, Sheer D, Trowsdale J . The human homologue of the mouse t-complex gene, TCP1, is located on chromosome 6 but is not near the HLA region . EMBO J . 6 . 7 . 1967–74 . Nov 1987 . 3653076 . 553584 . 10.1002/j.1460-2075.1987.tb02459.x.
3. Web site: Entrez Gene: TCP1 t-complex 1 .
4. Chen GI, Tisayakorn S, Jorgensen C, D'Ambrosio LM, Goudreault M, Gingras AC . PP4R4/KIAA1622 Forms a Novel Stable Cytosolic Complex with Phosphoprotein Phosphatase 4 . J. Biol. Chem. . 283 . 43 . 29273–84 . Oct 2008 . 18715871 . 2662017 . 10.1074/jbc.M803443200 . free.
5. Gingras AC, Caballero M, Zarske M, Sanchez A, Hazbun TR, Fields S, Sonenberg N, Hafen E, Raught B, Aebersold R . A novel, evolutionarily conserved protein phosphatase complex involved in cisplatin sensitivity . Mol. Cell. Proteomics . 4 . 11 . 1725–40 . Nov 2005 . 16085932 . 10.1074/mcp.M500231-MCP200 . free.
6. Guenther MG, Yu J, Kao GD, Yen TJ, Lazar MA . Assembly of the SMRT–histone deacetylase 3 repression complex requires the TCP-1 ring complex . Genes Dev. . 16 . 24 . 3130–5 . Dec 2002 . 12502735 . 187500 . 10.1101/gad.1037502.
7. Bakthavatsalam D, Soung RH, Tweardy DJ, Chiu W, Dixon RA, Woodside DG . Chaperonin-containing TCP-1 complex directly binds to the cytoplasmic domain of the LOX-1 receptor. . FEBS Lett . 588 . 13 . 2133–40 . Jun 2014 . 24846140 . 4100626 . 10.1016/j.febslet.2014.04.049.