1
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Zeng X, Geng W, Zhang Y, Yin J, Xu G, Yu M, Li L, Jia J. Thioredoxin-1 inhibits the activation of IRE1 by targeting Hsp90/p-Cdc37 chaperone complex in Parkinson disease. Ageing Res Rev 2023; 90:102000. [PMID: 37437766 DOI: 10.1016/j.arr.2023.102000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 04/11/2023] [Accepted: 07/03/2023] [Indexed: 07/14/2023]
Abstract
Endoplasmic reticulum stress is implicated in the etiopathogenesis of Parkinson disease (PD). Our previous study has revealed that thioredoxin-1 (Trx-1) attenuated IRE1 activation in 1-methyl-4-phenylpyridinium ion (MPP+)/1-methy-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD models. However, its exact mechanism has been largely unclear. In this research, it was reported for the first time that the protein levels of heat shock protein 90 (Hsp90) and phosphorylated cell division cycle 37 (p-Cdc37) were significantly decreased and the interaction of Hsp90/p-Cdc37 complex with IRE1 was disturbed in MPP+/MPTP-induced PD models. Trx-1 overexpression reversed the expression of Hsp90 and p-Cdc37 in cultured cells and the substantia nigra pars compacta of mice. More importantly, Trx-1 overexpression enhanced the interaction of Hsp90/p-Cdc37 complex with IRE1. In conclusion, our data demonstrated that Trx-1 inhibited IRE1 activation in PD by elevating the expression of Hsp90 and p-Cdc37 and strengthening the interaction of Hsp90/p-Cdc37 complex and IRE1.
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Affiliation(s)
- Xiansi Zeng
- Research Center of Neuroscience, Jiaxing University Medical College, Jiaxing 314001, China
| | - Wenshuo Geng
- College of Life Sciences, Xinyang Normal University, Xinyang 464000, China
| | - Yu Zhang
- Research Center of Neuroscience, Jiaxing University Medical College, Jiaxing 314001, China
| | - Jiayi Yin
- Research Center of Neuroscience, Jiaxing University Medical College, Jiaxing 314001, China
| | - Guangtao Xu
- Department of Pathology, Institute of Forensic Science, Jiaxing University, Jiaxing 314001, China
| | - Meng Yu
- Research Center of Neuroscience, Jiaxing University Medical College, Jiaxing 314001, China
| | - Li Li
- Research Center of Neuroscience, Jiaxing University Medical College, Jiaxing 314001, China
| | - Jinjing Jia
- Research Center of Neuroscience, Jiaxing University Medical College, Jiaxing 314001, China.
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2
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Bhadra S, Xu YJ. TTT (Tel2-Tti1-Tti2) Complex, the Co-Chaperone of PIKKs and a Potential Target for Cancer Chemotherapy. Int J Mol Sci 2023; 24:ijms24098268. [PMID: 37175973 PMCID: PMC10178989 DOI: 10.3390/ijms24098268] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 04/27/2023] [Accepted: 05/03/2023] [Indexed: 05/15/2023] Open
Abstract
The heterotrimeric Tel2-Tti1-Tti2 or TTT complex is essential for cell viability and highly observed in eukaryotes. As the co-chaperone of ATR, ATM, DNA-PKcs, mTOR, SMG1, and TRRAP, the phosphatidylinositol 3-kinase-related kinases (PIKKs) and a group of large proteins of 300-500 kDa, the TTT plays crucial roles in genome stability, cell proliferation, telomere maintenance, and aging. Most of the protein kinases in the kinome are targeted by co-chaperone Cdc37 for proper folding and stability. Like Cdc37, accumulating evidence has established the mechanism by which the TTT interacts with chaperone Hsp90 via R2TP (Rvb1-Rvb2-Tah1-Pih1) complex or other proteins for co-translational maturation of the PIKKs. Recent structural studies have revealed the α-solenoid structure of the TTT and its interactions with the R2TP complex, which shed new light on the co-chaperone mechanism and provide new research opportunities. A series of mutations of the TTT have been identified that cause disease syndrome with neurodevelopmental defects, and misregulation of the TTT has been shown to contribute to myeloma, colorectal, and non-small-cell lung cancers. Surprisingly, Tel2 in the TTT complex has recently been found to be a target of ivermectin, an antiparasitic drug that has been used by millions of patients. This discovery provides mechanistic insight into the anti-cancer effect of ivermectin and thus promotes the repurposing of this Nobel-prize-winning medicine for cancer chemotherapy. Here, we briefly review the discovery of the TTT complex, discuss the recent studies, and describe the perspectives for future investigation.
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Affiliation(s)
- Sankhadip Bhadra
- Department of Pharmacology and Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Yong-Jie Xu
- Department of Pharmacology and Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
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3
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Design of Disruptors of the Hsp90-Cdc37 Interface. Molecules 2020; 25:molecules25020360. [PMID: 31952296 PMCID: PMC7024268 DOI: 10.3390/molecules25020360] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/08/2020] [Accepted: 01/13/2020] [Indexed: 11/19/2022] Open
Abstract
The molecular chaperone Hsp90 is a ubiquitous ATPase-directed protein responsible for the activation and structural stabilization of a large clientele of proteins. As such, Hsp90 has emerged as a suitable candidate for the treatment of a diverse set of diseases, such as cancer and neurodegeneration. The inhibition of the chaperone through ATP-competitive inhibitors, however, was shown to lead to undesirable side effects. One strategy to alleviate this problem is the development of molecules that are able to disrupt specific protein–protein interactions, thus modulating the activity of Hsp90 only in the particular cellular pathway that needs to be targeted. Here, we exploit novel computational and theoretical approaches to design a set of peptides that are able to bind Hsp90 and compete for its interaction with the co-chaperone Cdc37, which is found to be responsible for the promotion of cancer cell proliferation. In spite of their capability to disrupt the Hsp90–Cdc37 interaction, no important cytotoxicity was observed in human cancer cells exposed to designed compounds. These findings imply the need for further optimization of the compounds, which may lead to new ways of interfering with the Hsp90 mechanisms that are important for tumour growth.
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4
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Ihama F, Yamamoto M, Kojima C, Fujiwara T, Matsuzaki K, Miyata Y, Hoshino M. Structural characterization of the N-terminal kinase-interacting domain of an Hsp90-cochaperone Cdc37 by CD and solution NMR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:813-820. [DOI: 10.1016/j.bbapap.2019.06.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 06/08/2019] [Accepted: 06/14/2019] [Indexed: 10/26/2022]
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5
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Regulation of the Hsp90 system. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:889-897. [PMID: 29563055 DOI: 10.1016/j.bbamcr.2018.03.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 03/13/2018] [Accepted: 03/14/2018] [Indexed: 01/01/2023]
Abstract
Hsp90 is a highly conserved and abundant chaperone. It participates in essential cellular activities by supporting the maturation process of its client proteins, many of which are protein kinases and steroid receptors. Client processing is achieved via extensive conformational changes within the dimeric chaperone. This requires an ATP hydrolysis activity that is controlled by auto-inhibitory mechanisms and several structurally diverse cofactors. Especially the client-specificity of Hsp90 depends on client-specific cofactors, which can adapt Hsp90's activities to the client requirements at different conditions and in different cell types. Additionally, post-translational modifications can influence almost every aspect of Hsp90's interactions and activities. In this review, we present these regulatory principles, discuss the factors that have an impact on Hsp90's function and elaborate the mechanisms that are responsible for regulating the Hsp90 machinery.
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6
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Bunney TD, Inglis AJ, Sanfelice D, Farrell B, Kerr CJ, Thompson GS, Masson GR, Thiyagarajan N, Svergun DI, Williams RL, Breeze AL, Katan M. Disease Variants of FGFR3 Reveal Molecular Basis for the Recognition and Additional Roles for Cdc37 in Hsp90 Chaperone System. Structure 2018; 26:446-458.e8. [PMID: 29478821 PMCID: PMC5846801 DOI: 10.1016/j.str.2018.01.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 12/06/2017] [Accepted: 01/26/2018] [Indexed: 11/21/2022]
Abstract
Receptor tyrosine kinase FGFR3 is involved in many signaling networks and is frequently mutated in developmental disorders and cancer. The Hsp90/Cdc37 chaperone system is essential for function of normal and neoplastic cells. Here we uncover the mechanistic inter-relationships between these proteins by combining approaches including NMR, HDX-MS, and SAXS. We show that several disease-linked mutations convert FGFR3 to a stronger client, where the determinant underpinning client strength involves an allosteric network through the N-lobe and at the lobe interface. We determine the architecture of the client kinase/Cdc37 complex and demonstrate, together with site-specific information, that binding of Cdc37 to unrelated kinases induces a common, extensive conformational remodeling of the kinase N-lobe, beyond localized changes and interactions within the binary complex. As further shown for FGFR3, this processing by Cdc37 deactivates the kinase and presents it, in a specific orientation established in the complex, for direct recognition by Hsp90.
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Affiliation(s)
- Tom D Bunney
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK.
| | - Alison J Inglis
- Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Domenico Sanfelice
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Brendan Farrell
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, Leeds LS2 9JT, UK
| | - Christopher J Kerr
- European Molecular Biology Laboratory (EMBL) Hamburg Outstation, DESY, Hamburg, Germany
| | - Gary S Thompson
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, Leeds LS2 9JT, UK
| | - Glenn R Masson
- Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Nethaji Thiyagarajan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Dmitri I Svergun
- European Molecular Biology Laboratory (EMBL) Hamburg Outstation, DESY, Hamburg, Germany
| | - Roger L Williams
- Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Alexander L Breeze
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, Leeds LS2 9JT, UK.
| | - Matilda Katan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK.
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7
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Progress in Molecular Chaperone Regulation of Heat Shock Protein 90 and Cancer. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2018. [DOI: 10.1016/s1872-2040(17)61071-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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8
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Booth L, Shuch B, Albers T, Roberts JL, Tavallai M, Proniuk S, Zukiwski A, Wang D, Chen CS, Bottaro D, Ecroyd H, Lebedyeva IO, Dent P. Multi-kinase inhibitors can associate with heat shock proteins through their NH2-termini by which they suppress chaperone function. Oncotarget 2017; 7:12975-96. [PMID: 26887051 PMCID: PMC4914336 DOI: 10.18632/oncotarget.7349] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Accepted: 01/16/2016] [Indexed: 12/03/2022] Open
Abstract
We performed proteomic studies using the GRP78 chaperone-inhibitor drug AR-12 (OSU-03012) as bait. Multiple additional chaperone and chaperone-associated proteins were shown to interact with AR-12, including: GRP75, HSP75, BAG2; HSP27; ULK-1; and thioredoxin. AR-12 down-regulated in situ immuno-fluorescence detection of ATP binding chaperones using antibodies directed against the NH2-termini of the proteins but only weakly reduced detection using antibodies directed against the central and COOH portions of the proteins. Traditional SDS-PAGE and western blotting assessment methods did not exhibit any alterations in chaperone detection. AR-12 altered the sub-cellular distribution of chaperone proteins, abolishing their punctate speckled patterning concomitant with changes in protein co-localization. AR-12 inhibited chaperone ATPase activity, which was enhanced by sildenafil; inhibited chaperone – chaperone and chaperone – client interactions; and docked in silico with the ATPase domains of HSP90 and of HSP70. AR-12 combined with sildenafil in a GRP78 plus HSP27 –dependent fashion to profoundly activate an eIF2α/ATF4/CHOP/Beclin1 pathway in parallel with inactivating mTOR and increasing ATG13 phosphorylation, collectively resulting in formation of punctate toxic autophagosomes. Over-expression of [GRP78 and HSP27] prevented: AR-12 –induced activation of ER stress signaling and maintained mTOR activity; AR-12 –mediated down-regulation of thioredoxin, MCL-1 and c-FLIP-s; and preserved tumor cell viability. Thus the inhibition of chaperone protein functions by AR-12 and by multi-kinase inhibitors very likely explains why these agents have anti-tumor effects in multiple genetically diverse tumor cell types.
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Affiliation(s)
- Laurence Booth
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Brian Shuch
- Urologic and Diagnostic Radiology, Yale School of Medicine, New Haven, CT 06520-8058, USA.,Urologic Oncology Branch, National Cancer Institute, Bethesda, MD 20892, USA
| | - Thomas Albers
- Department of Chemistry and Physics, Augusta University, Augusta, GA 30912, USA
| | - Jane L Roberts
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Mehrad Tavallai
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA 23298, USA
| | | | | | - Dasheng Wang
- Molecular and Translational Science, United States Medicinal Chemistry and Pharmacognosy, School of Pharmacy, The Ohio State University, Columbus, OH 43210, USA
| | - Ching-Shih Chen
- Molecular and Translational Science, United States Medicinal Chemistry and Pharmacognosy, School of Pharmacy, The Ohio State University, Columbus, OH 43210, USA
| | - Don Bottaro
- Urologic Oncology Branch, National Cancer Institute, Bethesda, MD 20892, USA
| | - Heath Ecroyd
- School of Biological Sciences and Illawarra Health and Medical Research Institute, University of Wollongong, NSW 2522, Australia
| | - Iryna O Lebedyeva
- Department of Chemistry and Physics, Augusta University, Augusta, GA 30912, USA
| | - Paul Dent
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA 23298, USA
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9
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Sahasrabudhe P, Rohrberg J, Biebl MM, Rutz DA, Buchner J. The Plasticity of the Hsp90 Co-chaperone System. Mol Cell 2017; 67:947-961.e5. [PMID: 28890336 DOI: 10.1016/j.molcel.2017.08.004] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 06/10/2017] [Accepted: 08/08/2017] [Indexed: 11/20/2022]
Abstract
The Hsp90 system in the eukaryotic cytosol is characterized by a cohort of co-chaperones that bind to Hsp90 and affect its function. Although progress has been made regarding the underlying biochemical mechanisms, how co-chaperones influence Hsp90 client proteins in vivo has remained elusive. By investigating the effect of 12 Hsp90 co-chaperones on the activity of different client proteins in yeast, we find that deletion of co-chaperones can have a neutral or negative effect on client activity but can also lead to more active clients. Only a few co-chaperones are active on all clients studied. Closely related clients and even point mutants can depend on different co-chaperones. These effects are direct because differences in client-co-chaperone interactions can be reconstituted in vitro. Interestingly, some co-chaperones affect client conformation in vivo. Thus, co-chaperones adapt the Hsp90 cycle to the requirements of the client proteins, ensuring optimal activation.
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Affiliation(s)
- Priyanka Sahasrabudhe
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, 85748 Garching, Germany
| | - Julia Rohrberg
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, 85748 Garching, Germany
| | - Maximillian M Biebl
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, 85748 Garching, Germany
| | - Daniel A Rutz
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, 85748 Garching, Germany
| | - Johannes Buchner
- Center for Integrated Protein Science at the Department of Chemistry, Technische Universität München, 85748 Garching, Germany.
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10
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Keramisanou D, Aboalroub A, Zhang Z, Liu W, Marshall D, Diviney A, Larsen RW, Landgraf R, Gelis I. Molecular Mechanism of Protein Kinase Recognition and Sorting by the Hsp90 Kinome-Specific Cochaperone Cdc37. Mol Cell 2017; 62:260-271. [PMID: 27105117 DOI: 10.1016/j.molcel.2016.04.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/29/2016] [Accepted: 04/04/2016] [Indexed: 12/29/2022]
Abstract
Despite the essential functions of Hsp90, little is known about the mechanism that controls substrate entry into its chaperone cycle. We show that the role of Cdc37 cochaperone reaches beyond that of an adaptor protein and find that it participates in the selective recruitment of only client kinases. Cdc37 recognizes kinase specificity determinants in both clients and nonclients and acts as a general kinase scanning factor. Kinase sorting within the client-to-nonclient continuum relies on the ability of Cdc37 to challenge the conformational stability of clients by locally unfolding them. This metastable conformational state has high affinity for Cdc37 and forms stable complexes through a multidomain cochaperone interface. The interaction with nonclients is not accompanied by conformational changes of the substrate and results in substrate dissociation. Collectively, Cdc37 performs a quality control of protein kinases, where induced conformational instability acts as a "flag" for Hsp90 dependence and stable cochaperone association.
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Affiliation(s)
| | - Adam Aboalroub
- Department of Chemistry, University of South Florida, Tampa, FL 33620, USA
| | - Ziming Zhang
- Department of Chemistry, University of South Florida, Tampa, FL 33620, USA
| | - Wenjun Liu
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Devon Marshall
- Department of Chemistry, University of South Florida, Tampa, FL 33620, USA
| | - Andrea Diviney
- Department of Chemistry, University of South Florida, Tampa, FL 33620, USA
| | - Randy W Larsen
- Department of Chemistry, University of South Florida, Tampa, FL 33620, USA
| | - Ralf Landgraf
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Ioannis Gelis
- Department of Chemistry, University of South Florida, Tampa, FL 33620, USA.
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11
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Yuan J, Zhang YM, Wu W, Ma W, Wang F. Effect of glycosides of Cistanche on the expression of mitochondrial precursor protein and keratin type II cytoskeletal 6A in a rat model of vascular dementia. Neural Regen Res 2017; 12:1152-1158. [PMID: 28852399 PMCID: PMC5558496 DOI: 10.4103/1673-5374.211196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Glycosides of Cistanche (GC) is a preparation used extensively for its neuroprotective effect against neurological diseases, but its mechanisms of action remains incompletely understood. Here, we established a bilateral common carotid artery occlusion model of vascular dementia in rats and injected the model rats with a suspension of GC (10 mg/kg/day, intraperitoneally) for 14 consecutive days. Immunohistochemistry showed that GC significantly reduced p-tau and amyloid beta (Aβ) immunoreactivity in the hippocampus of the model rats. Proteomic analysis demonstrated upregulation of mitochondrial precursor protein and downregulation of keratin type II cytoskeletal 6A after GC treatment compared with model rats that had received saline. Western blot assay confirmed these findings. Our results suggest that the neuroprotective effect of GC in vascular dementia occurs via the promotion of neuronal cytoskeleton regeneration.
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12
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Liu W, Barnette AR, Andreansky S, Landgraf R. ERBB2 Overexpression Establishes ERBB3-Dependent Hypersensitivity of Breast Cancer Cells to Withaferin A. Mol Cancer Ther 2016; 15:2750-2757. [PMID: 27474152 DOI: 10.1158/1535-7163.mct-15-0932] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 07/14/2016] [Indexed: 11/16/2022]
Abstract
The catalytically deficient ERBB3 strongly synergizes with the receptor tyrosine kinase ERBB2, and elevated levels represent an overall risk factor for unfavorable disease outcomes in breast cancer. Although itself not a target of pan-ERBB kinase inhibitors, it contributes to resistance in ERBB2-targeted treatment regiments. The steroidal lactone Withaferin A (WA) has established broad anticancer properties through several modes of action and was shown to be effective against triple-negative breast cancers at elevated concentrations. We found that ERBB2 overexpression does render cells hypersensitive to WA. Although ERBB2 downregulation is one aspect of WA treatment at high concentrations, it is not causal for the elevated sensitivity at lower dosages. Instead, WA targets the ability of ERBB3 to amplify ERBB2 signaling. ERBB3 receptor levels, constitutive phosphorylation of both ERBB3 and ERBB2, as well as signaling through AKT are eliminated by WA treatment. By targeting ERBB2/ERBB3 as a functional unit, it is also effective in cases in which ERBB2-directed inhibitors, such as lapatinib, alone show reduced potency. Hence, WA or derivatives thereof may present a low toxicity addition to ERBB2-targeting therapeutics, especially in cases in which ERBB3 involvement is driving resistance or reduced overall sensitivity. Mol Cancer Ther; 15(11); 2750-7. ©2016 AACR.
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Affiliation(s)
- Wenjun Liu
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida
| | - Annalise R Barnette
- Department of Microbiology and Immunology, Miller School of Medicine, University of Miami, Miami, Florida
| | - Samita Andreansky
- Department of Pediatrics, Miller School of Medicine, University of Miami, Miami, Florida.,Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Ralf Landgraf
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida. .,Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
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13
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Structural and functional basis of protein phosphatase 5 substrate specificity. Proc Natl Acad Sci U S A 2016; 113:9009-14. [PMID: 27466404 DOI: 10.1073/pnas.1603059113] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The serine/threonine phosphatase protein phosphatase 5 (PP5) regulates hormone- and stress-induced cellular signaling by association with the molecular chaperone heat shock protein 90 (Hsp90). PP5-mediated dephosphorylation of the cochaperone Cdc37 is essential for activation of Hsp90-dependent kinases. However, the details of this mechanism remain unknown. We determined the crystal structure of a Cdc37 phosphomimetic peptide bound to the catalytic domain of PP5. The structure reveals PP5 utilization of conserved elements of phosphoprotein phosphatase (PPP) structure to bind substrate and provides a template for many PPP-substrate interactions. Our data show that, despite a highly conserved structure, elements of substrate specificity are determined within the phosphatase catalytic domain itself. Structure-based mutations in vivo reveal that PP5-mediated dephosphorylation is required for kinase and steroid hormone receptor release from the chaperone complex. Finally, our data show that hyper- or hypoactivity of PP5 mutants increases Hsp90 binding to its inhibitor, suggesting a mechanism to enhance the efficacy of Hsp90 inhibitors by regulation of PP5 activity in tumors.
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14
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Verba KA, Wang RYR, Arakawa A, Liu Y, Shirouzu M, Yokoyama S, Agard DA. Atomic structure of Hsp90-Cdc37-Cdk4 reveals that Hsp90 traps and stabilizes an unfolded kinase. Science 2016; 352:1542-7. [PMID: 27339980 DOI: 10.1126/science.aaf5023] [Citation(s) in RCA: 293] [Impact Index Per Article: 36.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/13/2016] [Indexed: 12/20/2022]
Abstract
The Hsp90 molecular chaperone and its Cdc37 cochaperone help stabilize and activate more than half of the human kinome. However, both the mechanism by which these chaperones assist their "client" kinases and the reason why some kinases are addicted to Hsp90 while closely related family members are independent are unknown. Our structural understanding of these interactions is lacking, as no full-length structures of human Hsp90, Cdc37, or either of these proteins with a kinase have been elucidated. Here we report a 3.9 angstrom cryo-electron microscopy structure of the Hsp90-Cdc37-Cdk4 kinase complex. Surprisingly, the two lobes of Cdk4 are completely separated with the β4-β5 sheet unfolded. Cdc37 mimics part of the kinase N lobe, stabilizing an open kinase conformation by wedging itself between the two lobes. Finally, Hsp90 clamps around the unfolded kinase β5 strand and interacts with exposed N- and C-lobe interfaces, protecting the kinase in a trapped unfolded state. On the basis of this structure and an extensive amount of previously collected data, we propose unifying conceptual and mechanistic models of chaperone-kinase interactions.
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Affiliation(s)
- Kliment A Verba
- Howard Hughes Medical Institute (HHMI) and the Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA 94158, USA
| | - Ray Yu-Ruei Wang
- Howard Hughes Medical Institute (HHMI) and the Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA 94158, USA
| | - Akihiko Arakawa
- RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Yanxin Liu
- Howard Hughes Medical Institute (HHMI) and the Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA 94158, USA
| | - Mikako Shirouzu
- RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Shigeyuki Yokoyama
- RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - David A Agard
- Howard Hughes Medical Institute (HHMI) and the Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA 94158, USA.
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