TRAP1 - the mitochondrial HSP90: History
Please note this is an old version of this entry, which may differ significantly from the current revision.
Contributor: , , ,

The HSP90 paralog TRAP1 was discovered more than 20 years ago, however, a detailed understanding of the function of this mitochondrial molecular chaperone remains elusive. The dispensable nature of TRAP1 in vitro and in vivo further complicates an understanding of its role in mitochondrial biology. TRAP1 is more homologous to the bacterial HSP90, HtpG, than to eukaryotic HSP90. Lacking co-chaperones, the unique structural features of TRAP1 likely regulate its temperature-sensitive ATPase activity and shed light on the alternative mechanisms driving the chaperone’s nucleotide-dependent cycle in a defined environment whose physiological temperature approaches 50 °C. TRAP1 has been shown to be an important bioregulator of mitochondrial respiration, mediating the balance between oxidative phosphorylation and glycolysis, while at the same time promoting mitochondrial homeostasis and displaying cytoprotective activity. 

  • HSP90
  • TRAP1
  • molecular chaperone
  • mitochondria

1. Molecular Chaperones, HSP90 and TRAP1

Molecular chaperones form one of the central pillars of the cellular proteostasis network [1][2]. Depending upon their function, these molecules fall into three fundamental classes: foldases, holdases, and disaggregases [1][2][3][4][5][6][7]. Under certain circumstances, some molecular chaperones also deliver damaged and impossible to fold client proteins for degradation by proteosomes or autophagy [8][9][10]. Foldases are ATP-dependent chaperones that actively fold nascent proteins into their native functional conformations and refold unfolded proteins under cellular stress. Heat shock protein 90 (HSP90) is an ATP-dependent foldase that is remarkably conserved from bacteria to humans [11]. It regulates folding, maturation, and stability of proteins (in HSP90’s case, termed “clients”) that are involved in cell growth, survival, apoptosis, and adaptation to stress [12][13][14].
In mammalian cells there are four different HSP90 paralogs: HSP90α, HSP90β, GRP94, and TRAP1. HSP90α and HSP90β are primarily cytosolic with a small component in the nucleus. HSP90α is stress induced while HSP90β is constitutively expressed [15]. GRP94 is localized in the endoplasmic reticulum [16] and TRAP1 (or HSP75), the paralog on which researchers focused in this entry, is primarily localized in mitochondria [17][18]. TRAP1 was initially identified in 2000 [17] and was widely presumed to facilitate late-stage folding of clients in the mitochondrial matrix. However, it increasingly became clear that this may not be the case. TRAP1 has since been implicated in metabolic regulation [19][20][21][22][23][24][25], mitochondrial dynamics [26], mitophagy [27][28], protection from oxidative stress [23][29][30][31][32], and protection from cell death [33].

2. Is TRAP1 Cytoprotective or Pro-Neoplastic?

Although TRAP1 may have regulatory roles in organellar processes, whether it is ultimately cytoprotective in the context of neurodegenerative diseases or pro-neoplastic in the context of many cancers may reflect two sides of the same coin. This molecule has been reported to play a crucial role in inhibiting oxidative stress-induced tissue damage in the ischemic brain [34], hypoxia-induced injury in cardiomyocytes [35], myocardial ischemia/reperfusion injury [36], motor neuron degeneration in oxidative stress-induced amyotrophic lateral sclerosis (ALS) [37], and acidosis-induced injury in cardiomyocytes [38]. Likewise, TRAP1 appears to be protective in genetic models of neurodegeneration such as Parkinson’s disease [27][28][39] where protein quality control in mitochondria plays a critical role [40]. TRAP1 was also shown to be mitoprotective in models of kidney fibrosis and renal cell carcinoma [41][42]. Finally, loss-of-function TRAP1 mutations have been identified in the brain of a patient with Parkinson’s disease [43], Leigh syndrome [44], and chronic functional symptomatology including pain, fatigue, and gastrointestinal dysmotility [45], and in congenital abnormalities associated with the kidney (CAKUT) [46].
While these studies identify TRAP1 as cytoprotective in mitochondrial-associated neuropathologies, other studies have highlighted a potential pro-neoplastic role of TRAP1 in cancer, where it can also display cytoprotective and other pro-tumorigenic activities. Thus, TRAP1 expression was found to be increased in hepatocellular carcinoma [47], breast cancer [48], glioma [49], small cell lung cancer [50], and kidney, prostate, ovarian, colorectal, and esophageal cancer, and it is correlated with advanced-stage metastatic tumors with poor prognosis [51][52][53][54][55][56][57]. In colorectal cancer and its animal models, increased TRAP1 expression was found to be localized to pro-neoplastic lesions in the tumor [58][59]. While data supporting the importance of TRAP1 are numerous [24][47][48][49][50][51][52][53][54][55][56][57][59][60], these findings are challenged by other reports where TRAP1 expression inversely correlates with tumor stage [19] or is seemingly unimpactful in carcinogenesis models in TRAP1 knockout (KO) mice [61]. This has led to a general consensus that TRAP1’s role may be more context dependent.
Nevertheless, TRAP1 does appear to play a role in the metabolic adaptation that may sustain neoplastic growth in a nutrient- and oxygen-poor environment. This hypothesis has driven research to mechanistically elucidate a role played by TRAP1 that is common to various cancers. Thus, TRAP1 was reported to play a critical role in the metabolic switch from oxidative phosphorylation (OxPhos) to aerobic glycolysis [19]. This relationship of TRAP1 to metabolic plasticity sparked an interest in exploring the details of TRAP1 structure, interactome, mode of action, and inhibitors. The data that has emerged since has definitively highlighted TRAP1 as a major player in mitochondrial bioenergetics.

3. TRAP1 Structure, ATPase Cycle, Dimers, and Tetramers

The TRAP1 gene is evolutionarily conserved [62] and is found in both metazoans and protozoans but not in the budding yeast. Unlike HSP90, TRAP1 is not an essential protein, and TRAP1 KO mice or cells derived therefrom are viable [19][63]. Likewise, loss of TRAP1 function in a patient with Parkinson’s disease was unimpactful [43]. Similar to all members of the HSP90 family, TRAP1 has been primarily reported to form and function as a homodimer, with each protomer being comprised of an N-terminal ATPase domain (NTD), a middle domain (MD), and a C-terminal dimerization domain (CTD) [11][64][65]. The N-terminal domain contains a 59-amino acid mitochondrial-targeting sequence that is cleaved upon import [66]. Interestingly, TRAP1 more closely resembles bacterial HSP90 (HtpG) than human HSP90 [17][67]. As with HtpG, but unlike HSP90, TRAP1 lacks both a charged linker domain between the NTD and MD and a C-terminal EEVD motif that serves as a co-chaperone interaction domain in HSP90. TRAP1 also features an extended β-strand in the NTD, called “strap”, that facilitates a cross protomer interaction in trans in the closed state of TRAP1. Removal of the “strap” domain dramatically upregulates ATPase activity; this extension is considered to be involved in the thermoregulation of the TRAP1 ATPase and to be potentially inhibitory for TRAP1 function under low temperatures [68].
TRAP1 is a nucleotide-dependent and nucleotide-activated chaperone that exists as a coiled-coil dimer in an autoinhibited state in the absence of ATP [69]. The presence of ATP activates the TRAP1 homodimer, which cycles between an open “apo” state and a closed state involving a series of ATP-dependent steps that promote large conformational changes within the molecule [70]. Unlike the rest of the HSP90 family, TRAP1 has a unique ATP-bound catalytically active state that adopts a strained asymmetric conformation [71]. This unique asymmetry is most pronounced in the highly conserved client binding region and results from the buckling of one of the protomers onto the other [71]. Interestingly, ATP hydrolysis is sequential between the two protomers, with the dimer undergoing a “flip” in the asymmetry while still remaining in the closed state [71]. The first ATP hydrolysis step facilitates client folding while the second leads to client unloading and return to an apo state [68]. The Mg2+ ion is the primary choice of cofactor for the TRAP1 ATPase, but it can be replaced by Ca2+ [72]. Surprisingly, Ca2+-bound TRAP1 displays cooperative ATP hydrolysis and avoids asymmetric flipping of its protomers [72]. This may indicate that TRAP1 can function both as a foldase and a holdase, depending on its ionic environment.
Recently, TRAP1 was reported to form tetramers (dimer of dimers) [22], and it was proposed that the TRAP1 molecule exists in a dynamic equilibrium between a dimeric and a tetrameric state within mitochondria [22]. Analytical ultracentrifugation (AUC) with recombinant proteins further confirmed the existence of TRAP1 tetramers, which also seem to be stabilized in vitro by AMPPNP [73], a non-hydrolyzable structural homolog of ATP. Finally, cryo-EM analyses with purified proteins showed that the TRAP1 tetramer may adopt an orthogonal (butterfly), parallel, or antiparallel conformation (Figure 1) [73]. It should be noted that these observations are recent; any functional relevance of TRAP1 tetramers or for the potential transition between configurations remains unknown. Nevertheless, these observations are not entirely surprising when considering that crystallization of bacterial HtpG found the chaperone to exist as a dimer of dimers [74]. Similarly, HSP90 has also been reported to form such “oligomers” [75][76] under certain stimuli including elevated temperatures [77][78][79] and in the presence of non-ionic detergents or divalent cations [78][80].
Figure 1. The TRAP1 tetramer. Based on in vitro studies on HSP90 oligomerization, rapid alterations in temperature, chaperone activity, or local concentration of divalent cations, which are common occurrences in the mitochondria, may influence dimer–tetramer transition. Three distinct conformations have been observed for the TRAP1 tetramer in vitro: orthogonal, parallel, and antiparallel [22][73]. The conditions required for the adoption of or transition to a particular configuration are only predicted and remain unclear. A high-resolution MD-MD dimer–dimer interface has only been shown for the orthogonal structure (shown in the inset; adapted from Liu et. al., Biorxiv., 2020 [73]). Left and right sub-insets show interacting residues from protomer C (blue) to A (orange) and from A to C at the dimer–dimer interface, respectively.
Temperature-induced oligomerization of HSP90 is of particular interest in the context of TRAP1. This is because mitochondria operate close to 50 °C under physiological conditions, which is much higher than the 37 °C that is maintained in the adjacent cytosol [81]. To understand a physiological role of temperature-induced HSP90 oligomers, one study showed that self-oligomerized HSP90 under higher temperatures (>46 °C) readily binds to chemically unfolded dihydrofolate reductase (DHFR), a protein that could spontaneously refold by itself, to maintain it in a “folding-competent” state [79]. The binding of such a quaternary structure formed by HSP90 may actually provide an ideal environment for protein accommodation prior to folding and is consistent with a holdase function [82]. This hypothesis, while intriguing, definitely needs further experimental support. In the case of TRAP1, the existence of tetramers in “hot” mitochondria, the alterations in its asymmetry based on the availability of Mg2+ or Ca2+ ions, and a lack of significant proteome imbalance in TRAP1 KO cells [22] are consistent with the ability to adopt a holdase function in the mitochondrial environment. Additional experiments are needed to support or refute this hypothesis.

This entry is adapted from the peer-reviewed paper 10.3390/biom12070880

References

  1. Hartl, F.U.; Bracher, A.; Hayer-Hartl, M. Molecular chaperones in protein folding and proteostasis. Nature 2011, 475, 324–332.
  2. Kim, Y.E.; Hipp, M.S.; Bracher, A.; Hayer-Hartl, M.; Hartl, F.U. Molecular chaperone functions in protein folding and proteostasis. Annu. Rev. Biochem. 2013, 82, 323–355.
  3. Richter, K.; Haslbeck, M.; Buchner, J. The heat shock response: Life on the verge of death. Mol. Cell 2010, 40, 253–266.
  4. Gao, X.; Carroni, M.; Nussbaum-Krammer, C.; Mogk, A.; Nillegoda, N.B.; Szlachcic, A.; Guilbride, D.L.; Saibil, H.R.; Mayer, M.P.; Bukau, B. Human Hsp70 Disaggregase Reverses Parkinson’s-Linked α-Synuclein Amyloid Fibrils. Mol. Cell 2015, 59, 781–793.
  5. Nillegoda, N.B.; Bukau, B. Metazoan Hsp70-based protein disaggregases: Emergence and mechanisms. Front. Mol. Biosci. 2015, 2, 57.
  6. Fernandez-Funez, P.; Sanchez-Garcia, J.; de Mena, L.; Zhang, Y.; Levites, Y.; Khare, S.; Golde, T.E.; Rincon-Limas, D.E. Holdase activity of secreted Hsp70 masks amyloid-β42 neurotoxicity in Drosophila. Proc. Natl. Acad. Sci. USA 2016, 113, E5212–E5221.
  7. Thoma, J.; Burmann, B.M.; Hiller, S.; Müller, D.J. Impact of holdase chaperones Skp and SurA on the folding of β-barrel outer-membrane proteins. Nat. Struct. Mol. Biol. 2015, 22, 795–802.
  8. Demand, J.; Alberti, S.; Patterson, C.; Höhfeld, J. Cooperation of a ubiquitin domain protein and an E3 ubiquitin ligase during chaperone/proteasome coupling. Curr. Biol. 2001, 11, 1569–1577.
  9. Gamerdinger, M.; Hajieva, P.; Kaya, A.M.; Wolfrum, U.; Hartl, F.U.; Behl, C. Protein quality control during aging involves recruitment of the macroautophagy pathway by BAG3. EMBO J. 2009, 28, 889–901.
  10. Hartmann-Petersen, R.; Seeger, M.; Gordon, C. Transferring substrates to the 26S proteasome. Trends Biochem. Sci. 2003, 28, 26–31.
  11. Csermely, P.; Schnaider, T.; Soti, C.; Prohászka, Z.; Nardai, G. The 90-kDa molecular chaperone family: Structure, function, and clinical applications. A comprehensive review. Pharmacol. Ther. 1998, 79, 129–168.
  12. Schopf, F.H.; Biebl, M.M.; Buchner, J. The HSP90 chaperone machinery. Nat. Rev. Mol. Cell Biol. 2017, 18, 345–360.
  13. Radli, M.; Rüdiger, S.G.D. Dancing with the Diva: Hsp90–Client Interactions. J. Mol. Biol. 2018, 430, 3029–3040.
  14. Taipale, M.; Jarosz, D.F.; Lindquist, S. HSP90 at the hub of protein homeostasis: Emerging mechanistic insights. Nat. Rev. Mol. Cell Biol. 2010, 11, 515–528.
  15. Zuehlke, A.D.; Beebe, K.; Neckers, L.; Prince, T. Regulation and function of the human HSP90AA1 gene. Gene 2015, 570, 8–16.
  16. Marzec, M.; Eletto, D.; Argon, Y. GRP94: An HSP90-like protein specialized for protein folding and quality control in the endoplasmic reticulum. Biochim. Biophys. Acta 2012, 1823, 774–787.
  17. Felts, S.J.; Owen, B.A.; Nguyen, P.; Trepel, J.; Donner, D.B.; Toft, D.O. The hsp90-related protein TRAP1 is a mitochondrial protein with distinct functional properties. J. Biol. Chem. 2000, 275, 3305–3312.
  18. Cechetto, J.D.; Gupta, R.S. Immunoelectron microscopy provides evidence that tumor necrosis factor receptor-associated protein 1 (TRAP-1) is a mitochondrial protein which also localizes at specific extramitochondrial sites. Exp. Cell Res. 2000, 260, 30–39.
  19. Yoshida, S.; Tsutsumi, S.; Muhlebach, G.; Sourbier, C.; Lee, M.-J.; Lee, S.; Vartholomaiou, E.; Tatokoro, M.; Beebe, K.; Miyajima, N.; et al. Molecular chaperone TRAP1 regulates a metabolic switch between mitochondrial respiration and aerobic glycolysis. Proc. Natl. Acad. Sci. USA 2013, 110, E1604–E1612.
  20. Sciacovelli, M.; Guzzo, G.; Morello, V.; Frezza, C.; Zheng, L.; Nannini, N.; Calabrese, F.; Laudiero, G.; Esposito, F.; Landriscina, M.; et al. The Mitochondrial Chaperone TRAP1 Promotes Neoplastic Growth by Inhibiting Succinate Dehydrogenase. Cell Metab. 2013, 17, 988–999.
  21. Chae, Y.C.; Angelin, A.; Lisanti, S.; Kossenkov, A.V.; Speicher, K.D.; Wang, H.; Powers, J.F.; Tischler, A.S.; Pacak, K.; Fliedner, S.; et al. Landscape of the mitochondrial Hsp90 metabolome in tumours. Nat. Commun. 2013, 4, 2139.
  22. Joshi, A.; Dai, L.; Liu, Y.; Lee, J.; Ghahhari, N.M.; Segala, G.; Beebe, K.; Jenkins, L.M.; Lyons, G.C.; Bernasconi, L.; et al. The mitochondrial HSP90 paralog TRAP1 forms an OXPHOS-regulated tetramer and is involved in mitochondrial metabolic homeostasis. BMC Biol. 2020, 18, 10.
  23. Park, H.K.; Hong, J.H.; Oh, Y.T.; Kim, S.S.; Yin, J.; Lee, A.J.; Chae, Y.C.; Kim, J.H.; Park, S.H.; Park, C.K.; et al. Interplay between TRAP1 and Sirtuin-3 Modulates Mitochondrial Respiration and Oxidative Stress to Maintain Stemness of Glioma Stem Cells. Cancer Res. 2019, 79, 1369–1382.
  24. Rasola, A.; Neckers, L.; Picard, D. Mitochondrial oxidative phosphorylation TRAP(1)ped in tumor cells. Trends Cell Biol. 2014, 24, 455–463.
  25. Masgras, I.; Laquatra, C.; Cannino, G.; Serapian, S.A.; Colombo, G.; Rasola, A. The molecular chaperone TRAP1 in cancer: From the basics of biology to pharmacological targeting. Semin. Cancer Biol. 2021, 76, 45–53.
  26. Takamura, H.; Koyama, Y.; Matsuzaki, S.; Yamada, K.; Hattori, T.; Miyata, S.; Takemoto, K.; Tohyama, M.; Katayama, T. TRAP1 controls mitochondrial fusion/fission balance through Drp1 and Mff expression. PLoS ONE 2012, 7, e51912.
  27. Costa, A.C.; Loh, S.H.Y.; Martins, L.M. Drosophila Trap1 protects against mitochondrial dysfunction in a PINK1/parkin model of Parkinson’s disease. Cell Death Dis. 2013, 4, e467.
  28. Zhang, L.; Karsten, P.; Hamm, S.; Pogson, J.H.; Müller-Rischart, A.K.; Exner, N.; Haass, C.; Whitworth, A.J.; Winklhofer, K.F.; Schulz, J.B.; et al. TRAP1 rescues PINK1 loss-of-function phenotypes. Hum. Mol. Genet. 2013, 22, 2829–2841.
  29. Hua, G.; Zhang, Q.; Fan, Z. Heat Shock Protein 75 (TRAP1) Antagonizes Reactive Oxygen Species Generation and Protects Cells from Granzyme M-mediated Apoptosis. J. Biol. Chem. 2007, 282, 20553–20560.
  30. Montesano Gesualdi, N.; Chirico, G.; Pirozzi, G.; Costantino, E.; Landriscina, M.; Esposito, F. Tumor necrosis factor-associated protein 1 (TRAP-1) protects cells from oxidative stress and apoptosis. Stress 2007, 10, 342–350.
  31. Pridgeon, J.W.; Olzmann, J.A.; Chin, L.-S.; Li, L. PINK1 Protects against Oxidative Stress by Phosphorylating Mitochondrial Chaperone TRAP1. PLoS Biol. 2007, 5, e172.
  32. Ramos Rego, I.; Santos Cruz, B.; Ambrósio, A.F.; Alves, C.H. TRAP1 in Oxidative Stress and Neurodegeneration. Antioxidants 2021, 10, 1829.
  33. Kang, B.H.; Plescia, J.; Dohi, T.; Rosa, J.; Doxsey, S.J.; Altieri, D.C. Regulation of Tumor Cell Mitochondrial Homeostasis by an Organelle-Specific Hsp90 Chaperone Network. Cell 2007, 131, 257–270.
  34. Xu, L.; Voloboueva, L.A.; Ouyang, Y.; Emery, J.F.; Giffard, R.G. Overexpression of mitochondrial Hsp70/Hsp75 in rat brain protects mitochondria, reduces oxidative stress, and protects from focal ischemia. J. Cereb. Blood Flow Metab. 2009, 29, 365–374.
  35. Xiang, F.; Huang, Y.S.; Shi, X.H.; Zhang, Q. Mitochondrial chaperone tumour necrosis factor receptor-associated protein 1 protects cardiomyocytes from hypoxic injury by regulating mitochondrial permeability transition pore opening. FEBS J. 2010, 277, 1929–1938.
  36. Zhang, P.; Lu, Y.; Yu, D.; Zhang, D.; Hu, W. TRAP1 Provides Protection Against Myocardial Ischemia-Reperfusion Injury by Ameliorating Mitochondrial Dysfunction. Cell. Physiol. Biochem. Int. J. Exp. Cell. Physiol. Biochem. Pharmacol. 2015, 36, 2072–2082.
  37. Clarke, B.E.; Kalmar, B.; Greensmith, L. Enhanced Expression of TRAP1 Protects Mitochondrial Function in Motor Neurons under Conditions of Oxidative Stress. Int. J. Mol. Sci. 2022, 23, 1789.
  38. Zhang, L.; Su, N.; Luo, Y.; Chen, S.; Zhao, T. TRAP1 inhibits MIC60 ubiquitination to mitigate the injury of cardiomyocytes and protect mitochondria in extracellular acidosis. Cell Death Discov. 2021, 7, 389.
  39. Butler, E.K.; Voigt, A.; Lutz, A.K.; Toegel, J.P.; Gerhardt, E.; Karsten, P.; Falkenburger, B.; Reinartz, A.; Winklhofer, K.F.; Schulz, J.B. The mitochondrial chaperone protein TRAP1 mitigates α-Synuclein toxicity. PLoS Genet. 2012, 8, e1002488.
  40. Malpartida, A.B.; Williamson, M.; Narendra, D.P.; Wade-Martins, R.; Ryan, B.J. Mitochondrial Dysfunction and Mitophagy in Parkinson’s Disease: From Mechanism to Therapy. Trends Biochem. Sci. 2021, 46, 329–343.
  41. Chen, J.F.; Wu, Q.S.; Xie, Y.X.; Si, B.L.; Yang, P.P.; Wang, W.Y.; Hua, Q.; He, Q. TRAP1 ameliorates renal tubulointerstitial fibrosis in mice with unilateral ureteral obstruction by protecting renal tubular epithelial cell mitochondria. FASEB J. 2017, 31, 4503–4514.
  42. Nicolas, E.; Demidova, E.V.; Iqbal, W.; Serebriiskii, I.G.; Vlasenkova, R.; Ghatalia, P.; Zhou, Y.; Rainey, K.; Forman, A.F.; Dunbrack, R.L., Jr.; et al. Interaction of germline variants in a family with a history of early-onset clear cell renal cell carcinoma. Mol. Genet. Genom. Med. 2019, 7, e556.
  43. Fitzgerald, J.C.; Zimprich, A.; Carvajal Berrio, D.A.; Schindler, K.M.; Maurer, B.; Schulte, C.; Bus, C.; Hauser, A.K.; Kübler, M.; Lewin, R.; et al. Metformin reverses TRAP1 mutation-associated alterations in mitochondrial function in Parkinson’s disease. Brain J. Neurol. 2017, 140, 2444–2459.
  44. Skinner, S.J.; Doonanco, K.R.; Boles, R.G.; Chan, A.K.J. Homozygous TRAP1 sequence variant in a child with Leigh syndrome and normal kidneys. Kidney Int. 2014, 86, 860.
  45. Boles, R.G.; Hornung, H.A.; Moody, A.E.; Ortiz, T.B.; Wong, S.A.; Eggington, J.M.; Stanley, C.M.; Gao, M.; Zhou, H.; McLaughlin, S.; et al. Hurt, tired and queasy: Specific variants in the ATPase domain of the TRAP1 mitochondrial chaperone are associated with common, chronic “functional” symptomatology including pain, fatigue and gastrointestinal dysmotility. Mitochondrion 2015, 23, 64–70.
  46. Saisawat, P.; Kohl, S.; Hilger, A.C.; Hwang, D.Y.; Yung Gee, H.; Dworschak, G.C.; Tasic, V.; Pennimpede, T.; Natarajan, S.; Sperry, E.; et al. Whole-exome resequencing reveals recessive mutations in TRAP1 in individuals with CAKUT and VACTERL association. Kidney Int. 2014, 85, 1310–1317.
  47. Megger, D.A.; Bracht, T.; Kohl, M.; Ahrens, M.; Naboulsi, W.; Weber, F.; Hoffmann, A.-C.; Stephan, C.; Kuhlmann, K.; Eisenacher, M.; et al. Proteomic differences between hepatocellular carcinoma and nontumorous liver tissue investigated by a combined gel-based and label-free quantitative proteomics study. Mol. Cell. Proteom. 2013, 12, 2006–2020.
  48. Zhang, B.; Wang, J.; Huang, Z.; Wei, P.; Liu, Y.; Hao, J.; Zhao, L.; Zhang, F.; Tu, Y.; Wei, T. Aberrantly upregulated TRAP1 is required for tumorigenesis of breast cancer. Oncotarget 2015, 6, 44495.
  49. Li, S.; Lv, Q.; Sun, H.; Xue, Y.; Wang, P.; Liu, L.; Li, Z.; Li, Z.; Tian, X.; Liu, Y.H. Expression of TRAP1 predicts poor survival of malignant glioma patients. J. Mol. Neurosci. 2015, 55, 62–68.
  50. Lee, J.H.; Kang, K.W.; Kim, J.-E.; Hwang, S.W.; Park, J.H.; Kim, S.-H.; Ji, J.H.; Kim, T.G.; Nam, H.-Y.; Roh, M.S.; et al. Differential expression of heat shock protein 90 isoforms in small cell lung cancer. Int. J. Clin. Exp. Pathol. 2015, 8, 9487–9493.
  51. Gao, C.; Li, M.; Jiang, A.-L.; Sun, R.; Jin, H.-L.; Gui, H.-W.; Xiao, F.; Ding, X.-W.; Fu, Z.-M.; Feng, J.-P. Overexpression of the mitochondrial chaperone tumor necrosis factor receptor-associated protein 1 is associated with the poor prognosis of patients with colorectal cancer. Oncol. Lett. 2018, 15, 5451–5458.
  52. Gao, J.-Y.; Song, B.-R.; Peng, J.-J.; Lu, Y.-M. Correlation between mitochondrial TRAP-1 expression and lymph node metastasis in colorectal cancer. World J. Gastroenterol. 2012, 18, 5965–5971.
  53. Leav, I.; Plescia, J.; Goel, H.L.; Li, J.; Jiang, Z.; Cohen, R.J.; Languino, L.R.; Altieri, D.C. Cytoprotective mitochondrial chaperone TRAP-1 as a novel molecular target in localized and metastatic prostate cancer. Am. J. Pathol. 2010, 176, 393–401.
  54. Lv, Q.; Sun, H.; Cao, C.; Gao, B.; Qi, Y. Overexpression of tumor necrosis factor receptor-associated protein 1 (TRAP1) are associated with poor prognosis of epithelial ovarian cancer. Tumor Biol. J. Int. Soc. Oncodev. Biol. Med. 2016, 37, 2721–2727.
  55. Ou, Y.; Liu, L.; Xue, L.; Zhou, W.; Zhao, Z.; Xu, B.; Song, Y.; Zhan, Q. TRAP1 shows clinical significance and promotes cellular migration and invasion through STAT3/MMP2 pathway in human esophageal squamous cell cancer. J. Genet. Genom. Yi Chuan Xue Bao 2014, 41, 529–537.
  56. Pak, M.G.; Koh, H.J.; Roh, M.S. Clinicopathologic significance of TRAP1 expression in colorectal cancer: A large scale study of human colorectal adenocarcinoma tissues. Diagn. Pathol. 2017, 12, 6.
  57. Si, T.; Yang, G.; Qiu, X.; Luo, Y.; Liu, B.; Wang, B. Expression of tumor necrosis factor receptor-associated protein 1 and its clinical significance in kidney cancer. Int. J. Clin. Exp. Pathol. 2015, 8, 13090–13095.
  58. Chen, R.; Pan, S.; Lai, K.; Lai, L.A.; Crispin, D.A.; Bronner, M.P.; Brentnall, T.A. Up-regulation of mitochondrial chaperone TRAP1 in ulcerative colitis associated colorectal cancer. World J. Gastroenterol. 2014, 20, 17037–17048.
  59. Kowalik, M.A.; Guzzo, G.; Morandi, A.; Perra, A.; Menegon, S.; Masgras, I.; Trevisan, E.; Angioni, M.M.; Fornari, F.; Quagliata, L.; et al. Metabolic reprogramming identifies the most aggressive lesions at early phases of hepatic carcinogenesis. Oncotarget 2016, 7, 32375–32393.
  60. Wallace, D.C. Mitochondria and cancer. Nat. Rev. Cancer 2012, 12, 685–698.
  61. Vartholomaiou, E.; Madon-Simon, M.; Hagmann, S.; Mühlebach, G.; Wurst, W.; Floss, T.; Picard, D. Cytosolic Hsp90α and its mitochondrial isoform Trap1 are differentially required in a breast cancer model. Oncotarget 2017, 8, 17428.
  62. Chen, B.; Piel, W.H.; Gui, L.; Bruford, E.; Monteiro, A. The HSP90 family of genes in the human genome: Insights into their divergence and evolution. Genomics 2005, 86, 627–637.
  63. Lisanti, S.; Tavecchio, M.; Chae, Y.C.; Liu, Q.; Brice, A.K.; Thakur, M.L.; Languino, L.R.; Altieri, D.C. Deletion of the Mitochondrial Chaperone TRAP-1 Uncovers Global Reprogramming of Metabolic Networks. Cell Rep. 2014, 8, 671–677.
  64. Jackson, S.E. Hsp90: Structure and function. Top. Curr. Chem. 2013, 328, 155–240.
  65. Lavery, L.A.; Partridge, J.R.; Ramelot, T.A.; Elnatan, D.; Kennedy, M.A.; Agard, D.A. Structural asymmetry in the closed state of mitochondrial Hsp90 (TRAP1) supports a two-step ATP hydrolysis mechanism. Mol. Cell 2014, 53, 330–343.
  66. Kang, B.H. TRAP1 regulation of mitochondrial life or death decision in cancer cells and mitochondria-targeted TRAP1 inhibitors. BMB Rep. 2012, 45, 1–6.
  67. Tsutsumi, S.; Mollapour, M.; Prodromou, C.; Lee, C.T.; Panaretou, B.; Yoshida, S.; Mayer, M.P.; Neckers, L.M. Charged linker sequence modulates eukaryotic heat shock protein 90 (Hsp90) chaperone activity. Proc. Natl. Acad. Sci. USA 2012, 109, 2937–2942.
  68. Partridge, J.R.; Lavery, L.A.; Elnatan, D.; Naber, N.; Cooke, R.; Agard, D.A. A novel N-terminal extension in mitochondrial TRAP1 serves as a thermal regulator of chaperone activity. eLife 2014, 3, e03487.
  69. Sung, N.; Lee, J.; Kim, J.-H.; Chang, C.; Joachimiak, A.; Lee, S.; Tsai, F.T.F. Mitochondrial Hsp90 is a ligand-activated molecular chaperone coupling ATP binding to dimer closure through a coiled-coil intermediate. Proc. Natl. Acad. Sci. USA 2016, 113, 2952–2957.
  70. Leskovar, A.; Wegele, H.; Werbeck, N.D.; Buchner, J.; Reinstein, J. The ATPase cycle of the mitochondrial Hsp90 analog Trap1. J. Biol. Chem. 2008, 283, 11677–11688.
  71. Elnatan, D.; Betegon, M.; Liu, Y.; Ramelot, T.; Kennedy, M.A.; Agard, D.A. Symmetry broken and rebroken during the ATP hydrolysis cycle of the mitochondrial Hsp90 TRAP1. eLife 2017, 6, e25235.
  72. Elnatan, D.; Agard, D.A. Calcium binding to a remote site can replace magnesium as cofactor for mitochondrial Hsp90 (TRAP1) ATPase activity. J. Biol. Chem. 2018, 293, 13717–13724.
  73. Liu, Y.; Sun, M.; Elnatan, D.; Larson, A.G.; Agard, D.A. Cryo-EM analysis of human mitochondrial Hsp90 in multiple tetrameric states. bioRxiv 2020.
  74. Shiau, A.K.; Harris, S.F.; Southworth, D.R.; Agard, D.A. Structural Analysis of E. coli hsp90 reveals dramatic nucleotide-dependent conformational rearrangements. Cell 2006, 127, 329–340.
  75. Nemoto, T.; Sato, N. Oligomeric forms of the 90-kDa heat shock protein. Biochem. J. 1998, 330, 989–995.
  76. Lee, C.-C.; Lin, T.-W.; Ko, T.-P.; Wang, A.H.J. The Hexameric Structures of Human Heat Shock Protein 90. PLoS ONE 2011, 6, e19961.
  77. Chadli, A.; Ladjimi, M.M.; Baulieu, E.-E.; Catelli, M.G. Heat-induced Oligomerization of the Molecular Chaperone Hsp90: Inhibition by atp and geldanamycin and activation by transition metal oxyanions. J. Biol. Chem. 1999, 274, 4133–4139.
  78. Moullintraffort, L.; Bruneaux, M.; Nazabal, A.; Allegro, D.; Giudice, E.; Zal, F.; Peyrot, V.; Barbier, P.; Thomas, D.; Garnier, C. Biochemical and Biophysical Characterization of the Mg2+-induced 90-kDa Heat Shock Protein Oligomers. J. Biol. Chem. 2010, 285, 15100–15110.
  79. Yonehara, M.; Minami, Y.; Kawata, Y.; Nagai, J.; Yahara, I. Heat-induced Chaperone Activity of HSP90. J. Biol. Chem. 1996, 271, 2641–2645.
  80. Jakob, U.; Meyer, I.; Bügl, H.; André, S.; Bardwell, J.C.A.; Buchner, J. Structural Organization of Procaryotic and Eucaryotic Hsp90. Influence of divalent cations on structure and function. J. Biol. Chem. 1995, 270, 14412–14419.
  81. Chrétien, D.; Bénit, P.; Ha, H.-H.; Keipert, S.; El-Khoury, R.; Chang, Y.-T.; Jastroch, M.; Jacobs, H.T.; Rustin, P.; Rak, M. Mitochondria are physiologically maintained at close to 50 °C. PLoS Biol. 2018, 16, e2003992.
  82. Lepvrier, E.; Thomas, D.; Garnier, C. Hsp90 Quaternary Structures and the Chaperone Cycle: Highly Flexible Dimeric and Oligomeric Structures and Their Regulation by Co-Chaperones. Curr. Proteom. 2019, 16, 5–11.
More
This entry is offline, you can click here to edit this entry!