1
|
Sangar D, Hill E, Jack K, Batchelor M, Mistry B, Ribes JM, Jackson GS, Mead S, Bieschke J. Syntaxin-6 delays prion protein fibril formation and prolongs the presence of toxic aggregation intermediates. eLife 2024; 13:e83320. [PMID: 39109999 PMCID: PMC11377041 DOI: 10.7554/elife.83320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 07/20/2024] [Indexed: 09/06/2024] Open
Abstract
Prions replicate via the autocatalytic conversion of cellular prion protein (PrPC) into fibrillar assemblies of misfolded PrP. While this process has been extensively studied in vivo and in vitro, non-physiological reaction conditions of fibril formation in vitro have precluded the identification and mechanistic analysis of cellular proteins, which may alter PrP self-assembly and prion replication. Here, we have developed a fibril formation assay for recombinant murine and human PrP (23-231) under near-native conditions (NAA) to study the effect of cellular proteins, which may be risk factors or potential therapeutic targets in prion disease. Genetic screening suggests that variants that increase syntaxin-6 expression in the brain (gene: STX6) are risk factors for sporadic Creutzfeldt-Jakob disease. Analysis of the protein in NAA revealed, counterintuitively, that syntaxin-6 is a potent inhibitor of PrP fibril formation. It significantly delayed the lag phase of fibril formation at highly sub-stoichiometric molar ratios. However, when assessing toxicity of different aggregation time points to primary neurons, syntaxin-6 prolonged the presence of neurotoxic PrP species. Electron microscopy and super-resolution fluorescence microscopy revealed that, instead of highly ordered fibrils, in the presence of syntaxin-6 PrP formed less-ordered aggregates containing syntaxin-6. These data strongly suggest that the protein can directly alter the initial phase of PrP self-assembly and, uniquely, can act as an 'anti-chaperone', which promotes toxic aggregation intermediates by inhibiting fibril formation.
Collapse
Affiliation(s)
- Daljit Sangar
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| | - Elizabeth Hill
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| | - Kezia Jack
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| | - Mark Batchelor
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| | - Beenaben Mistry
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| | - Juan M Ribes
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| | - Graham S Jackson
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| | - Simon Mead
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| | - Jan Bieschke
- MRC Prion Unit at UCL, Institute of Prion Diseases, London, United Kingdom
| |
Collapse
|
2
|
Zhang K, Yin W, Ma L, Liu Z, Li Q. HSPB8 facilitates prostate cancer progression via activating the JAK/STAT3 signaling pathway. Biochem Cell Biol 2023; 101:1-11. [PMID: 36318825 DOI: 10.1139/bcb-2022-0205] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Prostate cancer (PC) is a clinically and biologically heterogeneous disease that lacks effective treatment. Heat shock protein B8 (HSPB8) is an important factor in the progression of various types of cancer. However, the clinical significance and biological role of HSPB8 in PC are still unclear. In this study, we determined HSPB8 expression in PC tissues by immunohistochemical staining and explored the in vitro functions of HSPB8 using HSPB8 knockdown DU145 and LNcap PC cell lines. The in vivo effect of HSPB8 was explored by a subcutaneous xenograft mice model. The human phospho-kinase array and signal transducer and activator of transcription (STAT) 3 activator were utilized to explore the potential mechanism of HSPB8-induced PC progression. As a result, we found that HSPB8 was abundantly expressed in PC tissues and cell lines. HSPB8 knockdown inhibited cell proliferation and migration, promoted apoptosis and cycle repression, as well as weakened tumorigenesis ability. Mechanistically, we demonstrated that HSPB8 facilitates the malignant phenotypes of PC by activating the Janus kinase/STAT3 signaling pathway. These results proposed that HSPB8 seems to be an attractive therapeutic target for PC patients.
Collapse
Affiliation(s)
- Kan Zhang
- Department of urinary surgery, Ningbo First Hospital, No.59, Liuting Street, Haishu District, Ningbo, Zhejiang Province 315000, China
| | - Weiqi Yin
- Department of urinary surgery, Ningbo First Hospital, No.59, Liuting Street, Haishu District, Ningbo, Zhejiang Province 315000, China
| | - Luping Ma
- Department of urinary surgery, First Affiliated Hospital School of Medicine, Shihezi University, No.107, North 2nd Road, Shihezi, Xinjiang Province 832008, China
| | - Zhili Liu
- Department of urinary surgery, First Affiliated Hospital School of Medicine, Shihezi University, No.107, North 2nd Road, Shihezi, Xinjiang Province 832008, China
| | - Qiang Li
- Department of urinary surgery, First Affiliated Hospital School of Medicine, Shihezi University, No.107, North 2nd Road, Shihezi, Xinjiang Province 832008, China
| |
Collapse
|
3
|
Singh G, Sarkar NK, Grover A. Hsp70, sHsps and ubiquitin proteins modulate HsfA6a-mediated Hsp101 transcript expression in rice (Oryza sativa L.). PHYSIOLOGIA PLANTARUM 2021; 173:2055-2067. [PMID: 34498290 DOI: 10.1111/ppl.13552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Hsp100 chaperones disaggregate the aggregated proteins and are vital for maintenance of protein homeostasis. The level of Hsp100 synthesised in the cells has a bearing on the survival of plants under heat stress. The Hsp100 transcription machinery is activated within minutes of the onset of heat stress. The heat shock factor HsfA6a plays a major role in the transcriptional regulation of the Hsp101 gene in rice plants. Through yeast-2-hybrid library screening, we identified small heat shock proteins (sHSPs), Hsp70 and ubiquitin as HsfA6a interacting proteins (HIPs). The bimolecular fluorescence complementation assays showed the physical interaction of HsfA6a with Hsp16.9A-CI and Hsp18.0-CII in the cytosolic region and with cHsp70-1 in the nucleus. With the Hsp101 promoter: reporter gene assays, using yeast cells and rice protoplasts, we show that CI-sHsps and CII-sHsps are negative regulators and Hsp70 positive regulator of the HsfA6a activity in modulation of Hsp101 transcription. We also noted that the HsfA6a interactors, Hsp70 and CI-sHsps and CII-sHsps, physically interact with each other. We noted that HsfA6a binds with the CI-sHsp and Hsp70 promoters, implying that HsfA6a has a role in transcriptional regulation of its interacting proteins. Furthermore, we noted that the mutation of the ubiquitin/sumoylation acceptor site lysine 10 to alanine (K10A) of HsfA6a enhanced its DNA binding potential on the Hsp101 promoter, implying that these modifiers are possibly involved in modulation of HsfA6a activity. Our work shows that Hsp70, CI-sHsps and CII-sHsp, and ubiquitin proteins coordinate with HsfA6a in mediating the Hsp101 transcription process in rice.
Collapse
Affiliation(s)
- Garima Singh
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, India
| | - Neelam K Sarkar
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, India
| | - Anil Grover
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi, India
| |
Collapse
|
4
|
Evangelisti A, Butler H, del Monte F. The Heart of the Alzheimer's: A Mindful View of Heart Disease. Front Physiol 2021; 11:625974. [PMID: 33584340 PMCID: PMC7873884 DOI: 10.3389/fphys.2020.625974] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 12/21/2020] [Indexed: 12/16/2022] Open
Abstract
Purpose of Review: This review summarizes the current evidence for the involvement of proteotoxicity and protein quality control systems defects in diseases of the central nervous and cardiovascular systems. Specifically, it presents the commonalities between the pathophysiology of protein misfolding diseases in the heart and the brain. Recent Findings: The involvement of protein homeostasis dysfunction has been for long time investigated and accepted as one of the leading pathophysiological causes of neurodegenerative diseases. In cardiovascular diseases instead the mechanistic focus had been on the primary role of Ca2+ dishomeostasis, myofilament dysfunction as well as extracellular fibrosis, whereas no attention was given to misfolding of proteins as a pathogenetic mechanism. Instead, in the recent years, several contributions have shown protein aggregates in failing hearts similar to the ones found in the brain and increasing evidence have highlighted the crucial importance that proteotoxicity exerts via pre-amyloidogenic species in cardiovascular diseases as well as the prominent role of the cellular response to misfolded protein accumulation. As a result, proteotoxicity, unfolding protein response (UPR), and ubiquitin-proteasome system (UPS) have recently been investigated as potential key pathogenic pathways and therapeutic targets for heart disease. Summary: Overall, the current knowledge summarized in this review describes how the misfolding process in the brain parallels in the heart. Understanding the folding and unfolding mechanisms involved early through studies in the heart will provide new knowledge for neurodegenerative proteinopathies and may prepare the stage for targeted and personalized interventions.
Collapse
Affiliation(s)
| | - Helen Butler
- School of Medicine, Department of Molecular and Cellular Biology and Pathobiology, Medical University of South Carolina, Charleston, SC, United States
| | - Federica del Monte
- Department of Medicine, Medical University of South Carolina, Charleston, SC, United States
| |
Collapse
|
5
|
The Activity and Stability of p56Lck and TCR Signaling Do Not Depend on the Co-Chaperone Cdc37. Int J Mol Sci 2020; 22:ijms22010126. [PMID: 33374422 PMCID: PMC7795971 DOI: 10.3390/ijms22010126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 11/16/2022] Open
Abstract
Lymphocyte-specific protein tyrosine kinase (Lck) is a pivotal tyrosine kinase involved in T cell receptor (TCR) signaling. Because of its importance, the activity of Lck is regulated at different levels including phosphorylation of tyrosine residues, protein-protein interactions, and localization. It has been proposed that the co-chaperone Cdc37, which assists the chaperone heat shock protein 90 (Hsp90) in the folding of client proteins, is also involved in the regulation of the activity/stability of Lck. Nevertheless, the available experimental data do not clearly support this conclusion. Thus, we assessed whether or not Cdc37 regulates Lck. We performed experiments in which the expression of Cdc37 was either augmented or suppressed in Jurkat T cells. The results of our experiments indicated that neither the overexpression nor the suppression of Cdc37 affected Lck stability and activity. Moreover, TCR signaling proceeded normally in T cells in which Cdc37 expression was either augmented or suppressed. Finally, we demonstrated that also under stress conditions Cdc37 was dispensable for the regulation of Lck activity/stability. In conclusion, our data do not support the idea that Lck is a Cdc37 client.
Collapse
|
6
|
Martinho MS, Nancarrow DJ, Lawrence TS, Beer DG, Ray D. Chaperones and Ubiquitin Ligases Balance Mutant p53 Protein Stability in Esophageal and Other Digestive Cancers. Cell Mol Gastroenterol Hepatol 2020; 11:449-464. [PMID: 33130332 PMCID: PMC7788241 DOI: 10.1016/j.jcmgh.2020.10.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 10/07/2020] [Accepted: 10/14/2020] [Indexed: 02/07/2023]
Abstract
The incidence of esophageal adenocarcinoma (EAC) and other gastrointestinal (GI) cancers have risen dramatically, thus defining the oncogenic drivers to develop effective therapies are necessary. Patients with Barrett's Esophagus (BE), have an elevated risk of developing EAC. Around 70%-80% of BE cases that progress to dysplasia and cancer have detectable TP53 mutations. Similarly, in other GI cancers higher rates of TP53 mutation are reported, which provide a significant survival advantage to dysplastic/cancer cells. Targeting molecular chaperones that mediate mutant p53 stability may effectively induce mutant p53 degradation and improve cancer outcomes. Statins can achieve this via disrupting the interaction between mutant p53 and the chaperone DNAJA1, promoting CHIP-mediated degradation of mutant p53, and statins are reported to significantly reduce the risk of BE progression to EAC. However, statins demonstrated sub-optimal efficacy depending on cancer types and TP53 mutation specificity. Besides the well-established role of MDM2 in p53 stability, we reported that individual isoforms of the E3 ubiquitin ligase GRAIL (RNF128) are critical, tissue-specific regulators of mutant p53 stability in BE progression to EAC, and targeting the interaction of mutant p53 with these isoforms may help mitigate EAC development. In this review, we discuss the critical ubiquitin-proteasome and chaperone regulation of mutant p53 stability in EAC and other GI cancers with future insights as to how to affect mutant p53 stability, further noting how the precise p53 mutation may influence the efficacy of treatment strategies and identifying necessary directions for further research in this field.
Collapse
Affiliation(s)
- May San Martinho
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan; Section of Thoracic Surgery, Department of Surgery, University of Michigan, Ann Arbor, Michigan
| | - Derek J Nancarrow
- Section of Thoracic Surgery, Department of Surgery, University of Michigan, Ann Arbor, Michigan
| | - Theodore S Lawrence
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan
| | - David G Beer
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan; Section of Thoracic Surgery, Department of Surgery, University of Michigan, Ann Arbor, Michigan
| | - Dipankar Ray
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan.
| |
Collapse
|
7
|
Gonos ES, Kapetanou M, Sereikaite J, Bartosz G, Naparło K, Grzesik M, Sadowska-Bartosz I. Origin and pathophysiology of protein carbonylation, nitration and chlorination in age-related brain diseases and aging. Aging (Albany NY) 2019; 10:868-901. [PMID: 29779015 PMCID: PMC5990388 DOI: 10.18632/aging.101450] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 05/08/2018] [Indexed: 12/11/2022]
Abstract
Non-enzymatic protein modifications occur inevitably in all living systems. Products of such modifications accumulate during aging of cells and organisms and may contribute to their age-related functional deterioration. This review presents the formation of irreversible protein modifications such as carbonylation, nitration and chlorination, modifications by 4-hydroxynonenal, removal of modified proteins and accumulation of these protein modifications during aging of humans and model organisms, and their enhanced accumulation in age-related brain diseases.
Collapse
Affiliation(s)
- Efstathios S Gonos
- National Hellenic Research Foundation, Institute of Biology, Medicinal Chemistry and Biotechnology, Athens 11635, Greece
| | - Marianna Kapetanou
- National Hellenic Research Foundation, Institute of Biology, Medicinal Chemistry and Biotechnology, Athens 11635, Greece.,Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Athens, Athens 15701, Greece
| | - Jolanta Sereikaite
- Department of Chemistry and Bioengineering, Faculty of Fundamental Sciences, Vilnius Gediminas Technical University, Vilnius 2040, Lithuania
| | - Grzegorz Bartosz
- Department of Molecular Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz 90-236, Poland
| | - Katarzyna Naparło
- Department of Analytical Biochemistry, Faculty of Biology and Agriculture, University of Rzeszow, Rzeszow 35-601, Poland
| | - Michalina Grzesik
- Department of Analytical Biochemistry, Faculty of Biology and Agriculture, University of Rzeszow, Rzeszow 35-601, Poland
| | - Izabela Sadowska-Bartosz
- Department of Analytical Biochemistry, Faculty of Biology and Agriculture, University of Rzeszow, Rzeszow 35-601, Poland
| |
Collapse
|
8
|
Baverstock K. Crick's sequence hypothesis - a review. Commun Integr Biol 2019; 12:59-64. [PMID: 31143364 PMCID: PMC6527182 DOI: 10.1080/19420889.2019.1594501] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 03/07/2019] [Indexed: 12/28/2022] Open
Abstract
Health care based on gene sequencing and genomics is increasingly becoming a reality: it is timely to review Crick’s sequence hypothesis for its fitness for this purpose. The sequence hypothesis is central to the prediction and correction of disease traits from gene sequence information. Considerable success in this respect has been achieved for rare diseases, but for the dominant part of the human disease burden, common diseases, little progress has been made since the completion of the sequencing of the human genome. It is argued here that the sequence hypothesis, namely the assumption that peptides will fold spontaneously to the native state protein, thus retaining the information coded in the originating genes, is not supported by a realistic physics-based assessment of the peptide to protein folding process.
Collapse
Affiliation(s)
- Keith Baverstock
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio Campus, Kuopio, Finland
| |
Collapse
|
9
|
Luciani M, Troncone L, Monte FD. Current and future circulating biomarkers for cardiac amyloidosis. Acta Pharmacol Sin 2018; 39:1133-1141. [PMID: 29770800 PMCID: PMC6289372 DOI: 10.1038/aps.2018.38] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 03/13/2018] [Indexed: 12/27/2022] Open
Abstract
Cardiac amyloidosis (CA) comprises a heterogeneous group of medical conditions affecting the myocardium. It presents with proteinaceous infiltration with variable degrees of severity, prevalence and evolution. Despite this heterogeneity, erroneous protein folding is the common pathophysiologic process, yielding the formation of a single misfolded protein (monomer) that progressively evolves and ultimately forms amyloid fibers. Additionally, by seeding out from the organs of origin, intermediates called oligomers metastasize and restart the process. Such self-echoing behavior makes the secondary affected organs as important as the primary ones. Unfortunately, CA can be clinically challenging and only suggestive in a late stage of its natural history, leaving a narrow therapeutic time window available. In light of the evolutionary nature of amyloidosis, here, we propose a new classification of the currently used biomarkers based on time stages with different specificity and applicability across CA subtypes. Early markers (free light chains, serum amyloid A, β2-microglobulin, osteopontin and osteoprotegerin) can be employed for disease detection. Intermediate markers [soluble suppression of tumorigenicity 2 (sST-2), midregional proadrenomedullin (MR-proADM), von Willebrand factor (vWF), hepatocyte growth factor (HGF), matrix metalloproteinases (MMPs) and tissue inhibitor metalloproteinases (TIMPs)] can provide information on the biological mechanisms of myocardial damage. As in heart failure, late-stage biomarkers (troponins and natriuretic peptides) can help clinicians with prognosis and therapeutic response evaluation in CA. Such findings have generated a remarkable foundation for our current knowledge on CA. Nevertheless, we envision a future class of biomarkers targeted at upstream events capable of detecting folding defects, which will ultimately expand the therapeutic window.
Collapse
Affiliation(s)
- Marco Luciani
- Herzzentrum, University Hospital of Zürich, Zürich, Switzerland.
| | - Luca Troncone
- Department of Cardiology, Brigham and Women's Hospital - Harvard Medical School, Boston, MA, USA
| | - Federica Del Monte
- Department of Medicine, Medical University of South Carolina, Charleston, SC, USA.
| |
Collapse
|
10
|
Akbari A, Bamdad F, Wu J. Chaperone-like food components: from basic concepts to food applications. Food Funct 2018; 9:3597-3609. [DOI: 10.1039/c7fo01902e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The significance of chaperones in preventing protein aggregation including amyloid fibril formation has been extensively documented in the biological field, but there is limited research on the potential effect of chaperone-like molecules on food protein functionality and food quality.
Collapse
Affiliation(s)
- Ali Akbari
- Department of Agricultural
- Food and Nutritional Science
- University of Alberta
- Edmonton
- Canada T6G2P5
| | - Fatemeh Bamdad
- Faculty of Pharmacy and Pharmaceutical Sciences
- University of Alberta
- Edmonton
- Canada T6G 2E1
| | - Jianping Wu
- Department of Agricultural
- Food and Nutritional Science
- University of Alberta
- Edmonton
- Canada T6G2P5
| |
Collapse
|
11
|
Cripwell RA, Rose SH, van Zyl WH. Expression and comparison of codon optimised Aspergillus tubingensis amylase variants in Saccharomyces cerevisiae. FEMS Yeast Res 2017. [DOI: 10.1093/femsyr/fox040] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
|
12
|
Zhang Y, Zhou X, Xu L, Wang L, Liu J, Ye J, Qiu P, Liu Q. Apoptosis of rat hepatic stellate cells induced by diallyl trisulfide and proteomics profiling in vitro. Can J Physiol Pharmacol 2017; 95:463-473. [PMID: 28177695 DOI: 10.1139/cjpp-2015-0527] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diallyl trisulfide (DATS), a major garlic derivative, inhibits cell proliferation and triggers apoptosis in a variety of cancer cell lines. However, the effects of DATS on hepatic stellate cells (HSCs) remain unknown. The aim of this study was to analyze the effects of DATS on cell proliferation and apoptosis, as well as the protein expression profile in rat HSCs. Rat HSCs were treated with or without 12 and 24 μg/mL DATS for various time intervals. Cell proliferation and apoptosis were determined using tetrazolium dye (MTT) colorimetric assay, bromodeoxyuridine (5-bromo-2'-deoxyuridine; BrdU) assay, Hoechst 33342 staining, electroscopy, and flow cytometry. Protein expression patterns in HSCs were systematically studied using 2-dimensional electrophoresis and mass spectrometry. DATS inhibited cell proliferation and induced apoptosis of HSCs in a time-dependent manner. We observed clear morphological changes in apoptotic HSCs and dramatically increased annexin V-positive - propidium iodide negative apoptosis compared with the untreated control group. Twenty-one significant differentially expressed proteins, including 9 downregulated proteins and 12 upregulated proteins, were identified after DATS administration, and most of them were involved in apoptosis. Our results suggest that DATS is an inducer of apoptosis in HSCs, and several key proteins may be involved in the molecular mechanism of apoptosis induced by DATS.
Collapse
Affiliation(s)
- Yajie Zhang
- a Department of Pathology, Guangzhou Medical University, Guangzhou, Guangdong Province, China
| | - Xiaoming Zhou
- a Department of Pathology, Guangzhou Medical University, Guangzhou, Guangdong Province, China
| | - Lipeng Xu
- b Institute of New Drug Research and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, Jinan University College of Pharmacy, Guangzhou, Guangdong Province, China
| | - Lulu Wang
- c Center of Community Health Services, The First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang Province, China
| | - Jinling Liu
- d Department of Digestive System Diseases, The First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang Province, China
| | - Jing Ye
- d Department of Digestive System Diseases, The First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang Province, China
| | - Pengxin Qiu
- e Department of Pharmacology, Zhong-Shan Medical College, Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Qinghua Liu
- f Department of Oncology, The First Affiliated Hospital, Shihezi University School of Medicine, Shihezi, Xinjiang Province, China
| |
Collapse
|
13
|
Anglès F, Castanié-Cornet MP, Slama N, Dinclaux M, Cirinesi AM, Portais JC, Létisse F, Genevaux P. Multilevel interaction of the DnaK/DnaJ(HSP70/HSP40) stress-responsive chaperone machine with the central metabolism. Sci Rep 2017; 7:41341. [PMID: 28128357 PMCID: PMC5269706 DOI: 10.1038/srep41341] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 12/16/2016] [Indexed: 12/23/2022] Open
Abstract
Networks of molecular chaperones maintain cellular protein homeostasis by acting at nearly every step in the biogenesis of proteins and protein complexes. Herein, we demonstrate that the major chaperone DnaK/HSP70 of the model bacterium Escherichia coli is critical for the proper functioning of the central metabolism and for the cellular response to carbon nutrition changes, either directly or indirectly via the control of the heat-shock response. We identified carbon sources whose utilization was positively or negatively affected by DnaK and isolated several central metabolism genes (among other genes identified in this work) that compensate for the lack of DnaK and/or DnaK/Trigger Factor chaperone functions in vivo. Using carbon sources with specific entry points coupled to NMR analyses of real-time carbon assimilation, metabolic coproducts production and flux rearrangements, we demonstrate that DnaK significantly impacts the hierarchical order of carbon sources utilization, the excretion of main coproducts and the distribution of metabolic fluxes, thus revealing a multilevel interaction of DnaK with the central metabolism.
Collapse
Affiliation(s)
- Fréderic Anglès
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 118 route de Narbonne, 31062 Toulouse Cedex 9, France.,LISBP, Université de Toulouse, CNRS, INRA, INSA F-31400 Toulouse, France
| | - Marie-Pierre Castanié-Cornet
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 118 route de Narbonne, 31062 Toulouse Cedex 9, France
| | - Nawel Slama
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 118 route de Narbonne, 31062 Toulouse Cedex 9, France
| | - Mickael Dinclaux
- LISBP, Université de Toulouse, CNRS, INRA, INSA F-31400 Toulouse, France
| | - Anne-Marie Cirinesi
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 118 route de Narbonne, 31062 Toulouse Cedex 9, France
| | | | - Fabien Létisse
- LISBP, Université de Toulouse, CNRS, INRA, INSA F-31400 Toulouse, France
| | - Pierre Genevaux
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, 118 route de Narbonne, 31062 Toulouse Cedex 9, France
| |
Collapse
|
14
|
Arlet JB, Guillem F, Lamarque M, Dussiot M, Maciel T, Moura I, Hermine O, Courtois G. Protein-based therapeutic for anemia caused by dyserythropoiesis. Expert Rev Proteomics 2016; 13:983-992. [PMID: 27661264 DOI: 10.1080/14789450.2016.1240622] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
INTRODUCTION Major advances have been recently made in understanding the molecular determinants of dyserythropoiesis, particularly due to recent works in β-thalassemia. The purpose of this review is devoted to underline the role of some proteins recently evidenced in the field, that may be new alternative therapeutic targets in the near future to alleviate different types of anemia. Areas covered: This review covers the contemporary aspects of some proteins involved in various types of dyserythropoiesis, including the transcriptional factor GATA-1 and its protective chaperone HSP70, but also cytokines of the transforming growth factor beta (TFG-β) family, TGF-β1 and GDF-11, and hormones as erythroferrone. It will be not exhaustive, but based on major recent published works from the literature in the past three years. Expert commentary: Sotatercept and lustatercept, two activin receptor II ligand traps that block GDF-11, are candidate drugs providing therapeutic hope in different types of ineffective erythropoiesis, including myelodysplastic syndromes (MDS) and β-thalassemia. Furthermore, a new concept emerges to consider erythroid lineage in the bone marrow as an endocrine gland.
Collapse
Affiliation(s)
- Jean-Benoît Arlet
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,b Service de Médecine Interne, Faculté de Médecine Paris Descartes, Sorbonne Paris-Cité et Assistance Publique-Hôpitaux de Paris , Hôpital européen Georges Pompidou , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Flavia Guillem
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Mathilde Lamarque
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France.,e Service d'Hématologie, Faculté de Médecine Paris Descartes , Sorbonne Paris-Cité et Assistance Publique-Hôpitaux de Paris Hôpital Necker , Paris , France
| | - Michael Dussiot
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Thiago Maciel
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Ivan Moura
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| | - Olivier Hermine
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France.,e Service d'Hématologie, Faculté de Médecine Paris Descartes , Sorbonne Paris-Cité et Assistance Publique-Hôpitaux de Paris Hôpital Necker , Paris , France
| | - Geneviève Courtois
- a Laboratoire INSERM UMR 1163 , CNRS ERL 8254 , Paris , France.,c Imagine Institute, Assistance Publique-Hôpitaux de Paris, Hôpital Necker , Université Paris Descartes, Sorbonne Paris Cité , Paris , France.,d Laboratory of Excellence GR-Ex , Paris , France
| |
Collapse
|
15
|
Kadibalban AS, Bogumil D, Landan G, Dagan T. DnaK-Dependent Accelerated Evolutionary Rate in Prokaryotes. Genome Biol Evol 2016; 8:1590-9. [PMID: 27189986 PMCID: PMC4898814 DOI: 10.1093/gbe/evw102] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Many proteins depend on an interaction with molecular chaperones in order to fold into a functional tertiary structure. Previous studies showed that protein interaction with the GroEL/GroES chaperonine and Hsp90 chaperone can buffer the impact of slightly deleterious mutations in the protein sequence. This capacity of GroEL/GroES to prevent protein misfolding has been shown to accelerate the evolution of its client proteins. Whether other bacterial chaperones have a similar effect on their client proteins is currently unknown. Here, we study the impact of DnaK (Hsp70) chaperone on the evolution of its client proteins. Evolutionary parameters were derived from comparison of the Escherichia coli proteome to 1,808,565 orthologous proteins in 1,149 proteobacterial genomes. Our analysis reveals a significant positive correlation between protein binding frequency with DnaK and evolutionary rate. Proteins with high binding affinity to DnaK evolve on average 4.3-fold faster than proteins in the lowest binding affinity class at the genus resolution. Differences in evolutionary rates of DnaK interactor classes are still significant after adjusting for possible effects caused by protein expression level. Furthermore, we observe an additive effect of DnaK and GroEL chaperones on the evolutionary rates of their common interactors. Finally, we found pronounced similarities in the physicochemical profiles that characterize proteins belonging to DnaK and GroEL interactomes. Our results thus implicate DnaK-mediated folding as a major component in shaping protein evolutionary dynamics in bacteria and supply further evidence for the long-term manifestation of chaperone-mediated folding on genome evolution.
Collapse
Affiliation(s)
- A Samer Kadibalban
- Institute of General Microbiology, Christian-Albrechts Universtiy of Kiel, Kiel, Germany
| | - David Bogumil
- Present address: The Department of Life Sciences & the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Giddy Landan
- Institute of General Microbiology, Christian-Albrechts Universtiy of Kiel, Kiel, Germany
| | - Tal Dagan
- Institute of General Microbiology, Christian-Albrechts Universtiy of Kiel, Kiel, Germany
| |
Collapse
|
16
|
Krysztofinska EM, Martínez-Lumbreras S, Thapaliya A, Evans NJ, High S, Isaacson RL. Structural and functional insights into the E3 ligase, RNF126. Sci Rep 2016; 6:26433. [PMID: 27193484 PMCID: PMC4872217 DOI: 10.1038/srep26433] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/03/2016] [Indexed: 12/14/2022] Open
Abstract
RNF126 is an E3 ubiquitin ligase that collaborates with the BAG6 sortase complex to ubiquitinate hydrophobic substrates in the cytoplasm that are destined for proteasomal recycling. Composed of a trimeric complex of BAG6, TRC35 and UBL4A the BAG6 sortase is also associated with SGTA, a co-chaperone from which it can obtain hydrophobic substrates. Here we solve the solution structure of the RNF126 zinc finger domain in complex with the BAG6 UBL domain. We also characterise an interaction between RNF126 and UBL4A and analyse the competition between SGTA and RNF126 for the N-terminal BAG6 binding site. This work sheds light on the sorting mechanism of the BAG6 complex and its accessory proteins which, together, decide the fate of stray hydrophobic proteins in the aqueous cytoplasm.
Collapse
Affiliation(s)
- Ewelina M. Krysztofinska
- Department of Chemistry, King’s College London, Britannia House, Trinity Street, London, SE1 1DB, UK
| | | | - Arjun Thapaliya
- Department of Chemistry, King’s College London, Britannia House, Trinity Street, London, SE1 1DB, UK
| | - Nicola J. Evans
- Department of Chemistry, King’s College London, Britannia House, Trinity Street, London, SE1 1DB, UK
| | - Stephen High
- Faculty of Life Sciences, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Rivka L. Isaacson
- Department of Chemistry, King’s College London, Britannia House, Trinity Street, London, SE1 1DB, UK
| |
Collapse
|
17
|
Mack KL, Shorter J. Engineering and Evolution of Molecular Chaperones and Protein Disaggregases with Enhanced Activity. Front Mol Biosci 2016; 3:8. [PMID: 27014702 PMCID: PMC4791398 DOI: 10.3389/fmolb.2016.00008] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 02/29/2016] [Indexed: 11/17/2022] Open
Abstract
Cells have evolved a sophisticated proteostasis network to ensure that proteins acquire and retain their native structure and function. Critical components of this network include molecular chaperones and protein disaggregases, which function to prevent and reverse deleterious protein misfolding. Nevertheless, proteostasis networks have limits, which when exceeded can have fatal consequences as in various neurodegenerative disorders, including Parkinson's disease and amyotrophic lateral sclerosis. A promising strategy is to engineer proteostasis networks to counter challenges presented by specific diseases or specific proteins. Here, we review efforts to enhance the activity of individual molecular chaperones or protein disaggregases via engineering and directed evolution. Remarkably, enhanced global activity or altered substrate specificity of various molecular chaperones, including GroEL, Hsp70, ClpX, and Spy, can be achieved by minor changes in primary sequence and often a single missense mutation. Likewise, small changes in the primary sequence of Hsp104 yield potentiated protein disaggregases that reverse the aggregation and buffer toxicity of various neurodegenerative disease proteins, including α-synuclein, TDP-43, and FUS. Collectively, these advances have revealed key mechanistic and functional insights into chaperone and disaggregase biology. They also suggest that enhanced chaperones and disaggregases could have important applications in treating human disease as well as in the purification of valuable proteins in the pharmaceutical sector.
Collapse
Affiliation(s)
- Korrie L Mack
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphia, PA, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphia, PA, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of PennsylvaniaPhiladelphia, PA, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine at the University of PennsylvaniaPhiladelphia, PA, USA
| |
Collapse
|
18
|
The GroEL-GroES Chaperonin Machine: A Nano-Cage for Protein Folding. Trends Biochem Sci 2015; 41:62-76. [PMID: 26422689 DOI: 10.1016/j.tibs.2015.07.009] [Citation(s) in RCA: 249] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Revised: 07/21/2015] [Accepted: 07/31/2015] [Indexed: 01/12/2023]
Abstract
The bacterial chaperonin GroEL and its cofactor GroES constitute the paradigmatic molecular machine of protein folding. GroEL is a large double-ring cylinder with ATPase activity that binds non-native substrate protein (SP) via hydrophobic residues exposed towards the ring center. Binding of the lid-shaped GroES to GroEL displaces the bound protein into an enlarged chamber, allowing folding to occur unimpaired by aggregation. GroES and SP undergo cycles of binding and release, regulated allosterically by the GroEL ATPase. Recent structural and functional studies are providing insights into how the physical environment of the chaperonin cage actively promotes protein folding, in addition to preventing aggregation. Here, we review different models of chaperonin action and discuss issues of current debate.
Collapse
|
19
|
Thomas JL, Bose HS. Regulation of human 3-beta-hydroxysteroid dehydrogenase type-2 (3βHSD2) by molecular chaperones and the mitochondrial environment affects steroidogenesis. J Steroid Biochem Mol Biol 2015; 151:74-84. [PMID: 25448736 DOI: 10.1016/j.jsbmb.2014.11.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/09/2014] [Accepted: 11/19/2014] [Indexed: 10/24/2022]
Abstract
Human 3-β-hydroxysteroid dehydrogenase/isomerase types 1 and 2 (3βHSD1 and 3βHSD2, respectively) are expressed in a tissue-specific pattern by different genes. Site-directed mutagenesis studies have confirmed the function of the catalytic amino acids (Tyr154, Lys 158, Ser124 in both isoenzymes), substrate/inhibitor isoform-specific residues (His156 and Arg195 in 3βHSD1) and cofactor binding residues (Asp36 provides NAD(+) specificity in both isoenzymes). However, detailed analysis of isoform-specific organelle localization and characterization is difficult due to the 93% amino acid identity between the two isoforms. With recent advances in the knowledge of mitochondrial architecture and localization of the various translocases, our laboratory has studied the mechanisms regulating mitochondrial 3βHSD2 localization. The mitochondrial N-terminal leader sequence of 3βHSD2 directs its entry into the mitochondria where it is localized to the intermembrane space (IMS). Unlike other mitochondrial proteins, the N-terminal signal sequence of 3βHSD2 is not cleaved upon mitochondrial import. 3βHSD2 interacts with the mitochondrial translocase, Tim50, to regulate progesterone and androstenedione formation. Our studies suggest that its activity at the IMS is facilitated in a partially unfolded "molten globule" conformation by the proton pump between the matrix and IMS. The unfolded protein is refolded by the mitochondrial chaperones. The protons at the IMS are absorbed by the lipid vesicles, to maintain the proton pump and recycle 3βHSD2. As a result, one molecule of 3βHSD2 may participate in multiple catalytic reactions. In summary, the steroidogenic cell recycles 3βHSD2 to catalyze the reactions needed to produce androstenedione, progesterone and 17α-hydroxyprogesterone on demand in coordination with the mitochondrial translocase, Tim50. This article is part of a Special Issue entitled 'Steroid/Sterol signaling'.
Collapse
Affiliation(s)
- James L Thomas
- Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, GA 31207, USA
| | - Himangshu S Bose
- Departments of Biochemistry, Biomedical Sciences, Mercer University School of Medicine, Savannah, GA 31404, USA; Memorial University Medical Center, Anderson Cancer Institute, Savannah, GA 31404, USA.
| |
Collapse
|
20
|
Yang F, Yang X, Li Z, Du C, Wang J, Li S. Overexpression and characterization of a glucose-tolerant β-glucosidase from T. aotearoense with high specific activity for cellobiose. Appl Microbiol Biotechnol 2015; 99:8903-15. [DOI: 10.1007/s00253-015-6619-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 04/07/2015] [Accepted: 04/10/2015] [Indexed: 12/20/2022]
|
21
|
Pharmacological folding chaperones act as allosteric ligands of Frizzled4. Nat Chem Biol 2015; 11:280-6. [DOI: 10.1038/nchembio.1770] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 02/10/2015] [Indexed: 02/01/2023]
|
22
|
Trösch R, Mühlhaus T, Schroda M, Willmund F. ATP-dependent molecular chaperones in plastids--More complex than expected. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:872-88. [PMID: 25596449 DOI: 10.1016/j.bbabio.2015.01.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/03/2015] [Accepted: 01/08/2015] [Indexed: 11/27/2022]
Abstract
Plastids are a class of essential plant cell organelles comprising photosynthetic chloroplasts of green tissues, starch-storing amyloplasts of roots and tubers or the colorful pigment-storing chromoplasts of petals and fruits. They express a few genes encoded on their organellar genome, called plastome, but import most of their proteins from the cytosol. The import into plastids, the folding of freshly-translated or imported proteins, the degradation or renaturation of denatured and entangled proteins, and the quality-control of newly folded proteins all require the action of molecular chaperones. Members of all four major families of ATP-dependent molecular chaperones (chaperonin/Cpn60, Hsp70, Hsp90 and Hsp100 families) have been identified in plastids from unicellular algae to higher plants. This review aims not only at giving an overview of the most current insights into the general and conserved functions of these plastid chaperones, but also into their specific plastid functions. Given that chloroplasts harbor an extreme environment that cycles between reduced and oxidized states, that has to deal with reactive oxygen species and is highly reactive to environmental and developmental signals, it can be presumed that plastid chaperones have evolved a plethora of specific functions some of which are just about to be discovered. Here, the most urgent questions that remain unsolved are discussed, and guidance for future research on plastid chaperones is given. This article is part of a Special Issue entitled: Chloroplast Biogenesis.
Collapse
Affiliation(s)
- Raphael Trösch
- TU Kaiserslautern, Molecular Biotechnology & Systems Biology, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany; HU Berlin, Institute of Biology, Chausseestraße 117, 10115 Berlin, Germany; TU Kaiserslautern, Molecular Genetics of Eukaryotes, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany.
| | - Timo Mühlhaus
- TU Kaiserslautern, Molecular Biotechnology & Systems Biology, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany.
| | - Michael Schroda
- TU Kaiserslautern, Molecular Biotechnology & Systems Biology, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany.
| | - Felix Willmund
- TU Kaiserslautern, Molecular Genetics of Eukaryotes, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany.
| |
Collapse
|
23
|
McMorran LM, Brockwell DJ, Radford SE. Mechanistic studies of the biogenesis and folding of outer membrane proteins in vitro and in vivo: what have we learned to date? Arch Biochem Biophys 2014; 564:265-80. [PMID: 24613287 PMCID: PMC4262575 DOI: 10.1016/j.abb.2014.02.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 02/16/2014] [Accepted: 02/20/2014] [Indexed: 11/17/2022]
Abstract
Research into the mechanisms by which proteins fold into their native structures has been on-going since the work of Anfinsen in the 1960s. Since that time, the folding mechanisms of small, water-soluble proteins have been well characterised. By contrast, progress in understanding the biogenesis and folding mechanisms of integral membrane proteins has lagged significantly because of the need to create a membrane mimetic environment for folding studies in vitro and the difficulties in finding suitable conditions in which reversible folding can be achieved. Improved knowledge of the factors that promote membrane protein folding and disfavour aggregation now allows studies of folding into lipid bilayers in vitro to be performed. Consequently, mechanistic details and structural information about membrane protein folding are now emerging at an ever increasing pace. Using the panoply of methods developed for studies of the folding of water-soluble proteins. This review summarises current knowledge of the mechanisms of outer membrane protein biogenesis and folding into lipid bilayers in vivo and in vitro and discusses the experimental techniques utilised to gain this information. The emerging knowledge is beginning to allow comparisons to be made between the folding of membrane proteins with current understanding of the mechanisms of folding of water-soluble proteins.
Collapse
Affiliation(s)
- Lindsay M McMorran
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK; School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - David J Brockwell
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK; School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK; School of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, UK.
| |
Collapse
|
24
|
Mendez-Arroyo J, Barroso-Flores J, Lifschitz AM, Sarjeant AA, Stern CL, Mirkin CA. A Multi-State, Allosterically-Regulated Molecular Receptor With Switchable Selectivity. J Am Chem Soc 2014; 136:10340-8. [DOI: 10.1021/ja503506a] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Jose Mendez-Arroyo
- Department
of Chemistry and International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Joaquín Barroso-Flores
- Centro
Conjunto de Investigación en Química Sustentable, UAEM-UNAM, Carretera Toluca-Atlacomulco Km 14.5, Unidad San Cayetano, Toluca, Estado de México C. P. 50200, México
| | - Alejo M. Lifschitz
- Department
of Chemistry and International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Amy A. Sarjeant
- Department
of Chemistry and International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Charlotte L. Stern
- Department
of Chemistry and International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Chad A. Mirkin
- Department
of Chemistry and International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| |
Collapse
|
25
|
Theillet FX, Binolfi A, Frembgen-Kesner T, Hingorani K, Sarkar M, Kyne C, Li C, Crowley PB, Gierasch L, Pielak GJ, Elcock AH, Gershenson A, Selenko P. Physicochemical properties of cells and their effects on intrinsically disordered proteins (IDPs). Chem Rev 2014; 114:6661-714. [PMID: 24901537 PMCID: PMC4095937 DOI: 10.1021/cr400695p] [Citation(s) in RCA: 338] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Indexed: 02/07/2023]
Affiliation(s)
- Francois-Xavier Theillet
- Department
of NMR-supported Structural Biology, In-cell NMR Laboratory, Leibniz Institute of Molecular Pharmacology (FMP Berlin), Robert-Roessle Strasse 10, 13125 Berlin, Germany
| | - Andres Binolfi
- Department
of NMR-supported Structural Biology, In-cell NMR Laboratory, Leibniz Institute of Molecular Pharmacology (FMP Berlin), Robert-Roessle Strasse 10, 13125 Berlin, Germany
| | - Tamara Frembgen-Kesner
- Department
of Biochemistry, University of Iowa, Bowen Science Building, 51 Newton
Road, Iowa City, Iowa 52242, United States
| | - Karan Hingorani
- Departments
of Biochemistry & Molecular Biology and Chemistry, Program in
Molecular & Cellular Biology, University
of Massachusetts, Amherst, 240 Thatcher Way, Amherst, Massachusetts 01003, United States
| | - Mohona Sarkar
- Department
of Chemistry, Department of Biochemistry and Biophysics and Lineberger
Comprehensive Cancer Center, University
of North Carolina, Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Ciara Kyne
- School
of Chemistry, National University of Ireland,
Galway, University Road, Galway, Ireland
| | - Conggang Li
- Key Laboratory
of Magnetic Resonance in Biological Systems, State Key Laboratory
of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center
for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, P.R. China
| | - Peter B. Crowley
- School
of Chemistry, National University of Ireland,
Galway, University Road, Galway, Ireland
| | - Lila Gierasch
- Departments
of Biochemistry & Molecular Biology and Chemistry, Program in
Molecular & Cellular Biology, University
of Massachusetts, Amherst, 240 Thatcher Way, Amherst, Massachusetts 01003, United States
| | - Gary J. Pielak
- Department
of Chemistry, Department of Biochemistry and Biophysics and Lineberger
Comprehensive Cancer Center, University
of North Carolina, Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Adrian H. Elcock
- Department
of Biochemistry, University of Iowa, Bowen Science Building, 51 Newton
Road, Iowa City, Iowa 52242, United States
| | - Anne Gershenson
- Departments
of Biochemistry & Molecular Biology and Chemistry, Program in
Molecular & Cellular Biology, University
of Massachusetts, Amherst, 240 Thatcher Way, Amherst, Massachusetts 01003, United States
| | - Philipp Selenko
- Department
of NMR-supported Structural Biology, In-cell NMR Laboratory, Leibniz Institute of Molecular Pharmacology (FMP Berlin), Robert-Roessle Strasse 10, 13125 Berlin, Germany
| |
Collapse
|
26
|
Wang X, Chen M, Zhou J, Zhang X. HSP27, 70 and 90, anti-apoptotic proteins, in clinical cancer therapy (Review). Int J Oncol 2014; 45:18-30. [PMID: 24789222 DOI: 10.3892/ijo.2014.2399] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Accepted: 02/27/2014] [Indexed: 12/16/2022] Open
Abstract
Among the heat shock proteins (HSP), HSP27, HSP70 and HSP90 are the most studied stress-inducible HSPs, and are induced in response to a wide variety of physiological and environmental insults, thus allowing cells to survive to lethal conditions based on their powerful cytoprotective functions. Different functions of HSPs have been described to explain their cytoprotective functions, including their most basic role as molecular chaperones, that is to regulate protein folding, transport, translocation and assembly, especially helping in the refolding of misfolded proteins, as well as their anti-apoptotic properties. In cancer cells, the expression and/or activity of the three HSPs is abnormally high, and is associated with increased tumorigenicity, metastatic potential of cancer cells and resistance to chemotherapy. Associating with key apoptotic factors, they are powerful anti-apoptotic proteins, having the capacity to block the cell death process at different levels. Altogether, the properties suggest that HSP27, HSP70 and HSP90 are appropriate targets for modulating cell death pathways. In this review, we summarize the role of HSP90, HSP70 and HSP27 in apoptosis and the emerging strategies that have been developed for cancer therapy based on the inhibition of the three HSPs.
Collapse
Affiliation(s)
- Xiaoxia Wang
- College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, P.R. China
| | - Meijuan Chen
- College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, P.R. China
| | - Jing Zhou
- College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, P.R. China
| | - Xu Zhang
- College of Basic Medicine, Nanjing University of Chinese Medicine, Nanjing 210046, P.R. China
| |
Collapse
|
27
|
Bujalowski PJ, Oberhauser AF. Tracking unfolding and refolding reactions of single proteins using atomic force microscopy methods. Methods 2013; 60:151-60. [PMID: 23523554 DOI: 10.1016/j.ymeth.2013.03.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 03/07/2013] [Accepted: 03/11/2013] [Indexed: 11/26/2022] Open
Abstract
During the last two decades single-molecule manipulation techniques such as atomic force microscopy (AFM) has risen to prominence through their unique capacity to provide fundamental information on the structure and function of biomolecules. Here we describe the use of single-molecule AFM to track protein unfolding and refolding pathways, enzymatic catalysis and the effects of osmolytes and chaperones on protein stability and folding. We will outline the principles of operation for two different AFM pulling techniques: length clamp and force-clamp and discuss prominent applications. We provide protocols for the construction of polyproteins which are amenable for AFM experiments, the preparation of different coverslips, choice and calibration of AFM cantilevers. We also discuss the selection criteria for AFM recordings, the calibration of AFM cantilevers, protein sample preparations and analysis of the obtained data.
Collapse
Affiliation(s)
- Paul J Bujalowski
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, TX 77555, USA
| | | |
Collapse
|
28
|
The small heat-shock protein αB-crystallin uses different mechanisms of chaperone action to prevent the amorphous versus fibrillar aggregation of α-lactalbumin. Biochem J 2013; 448:343-52. [PMID: 23005341 DOI: 10.1042/bj20121187] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Stress conditions can destabilize proteins, promoting them to unfold and adopt intermediately folded states. Partially folded protein intermediates are unstable and prone to aggregation down off-folding pathways leading to the formation of either amorphous or amyloid fibril aggregates. The sHsp (small heat-shock protein) αB-crystallin acts as a molecular chaperone to prevent both amorphous and fibrillar protein aggregation; however, the precise molecular mechanisms behind its chaperone action are incompletely understood. To investigate whether the chaperone activity of αB-crystallin is dependent upon the form of aggregation (amorphous compared with fibrillar), bovine α-lactalbumin was developed as a model target protein that could be induced to aggregate down either off-folding pathway using comparable buffer conditions. Thus when α-lactalbumin was reduced it aggregated amorphously, whereas a reduced and carboxymethylated form aggregated to form amyloid fibrils. Using this model, αB-crystallin was shown to be a more efficient chaperone against amorphously aggregating α-lactalbumin than when it aggregated to form fibrils. Moreover, αB-crystallin forms high molecular mass complexes with α-lactalbumin to prevent its amorphous aggregation, but prevents fibril formation via weak transient interactions. Thus, the conformational stability of the protein intermediate, which is a precursor to aggregation, plays a critical role in modulating the chaperone mechanism of αB-crystallin.
Collapse
|
29
|
A bacteriophage-encoded J-domain protein interacts with the DnaK/Hsp70 chaperone and stabilizes the heat-shock factor σ32 of Escherichia coli. PLoS Genet 2012; 8:e1003037. [PMID: 23133404 PMCID: PMC3486835 DOI: 10.1371/journal.pgen.1003037] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 09/04/2012] [Indexed: 01/21/2023] Open
Abstract
The universally conserved J-domain proteins (JDPs) are obligate cochaperone partners of the Hsp70 (DnaK) chaperone. They stimulate Hsp70's ATPase activity, facilitate substrate delivery, and confer specific cellular localization to Hsp70. In this work, we have identified and characterized the first functional JDP protein encoded by a bacteriophage. Specifically, we show that the ORFan gene 057w of the T4-related enterobacteriophage RB43 encodes a bona fide JDP protein, named Rki, which specifically interacts with the Escherichia coli host multifunctional DnaK chaperone. However, in sharp contrast with the three known host JDP cochaperones of DnaK encoded by E. coli, Rki does not act as a generic cochaperone in vivo or in vitro. Expression of Rki alone is highly toxic for wild-type E. coli, but toxicity is abolished in the absence of endogenous DnaK or when the conserved J-domain of Rki is mutated. Further in vivo analyses revealed that Rki is expressed early after infection by RB43 and that deletion of the rki gene significantly impairs RB43 proliferation. Furthermore, we show that mutations in the host dnaK gene efficiently suppress the growth phenotype of the RB43 rki deletion mutant, thus indicating that Rki specifically interferes with DnaK cellular function. Finally, we show that the interaction of Rki with the host DnaK chaperone rapidly results in the stabilization of the heat-shock factor σ32, which is normally targeted for degradation by DnaK. The mechanism by which the Rki-dependent stabilization of σ32 facilitates RB43 bacteriophage proliferation is discussed. Bacteriophages are the most abundant biological entities on earth. As a consequence, they represent the largest reservoir of unexplored genetic information. They control bacterial growth, mediate horizontal gene transfer, and thus exert profound influence on microbial ecology and growth. One of the striking features of bacteriophages is that they code for many open reading frames of thus far unknown biological function (called ORFans), which have been referred to as the dark matter of our biosphere. Here we have extensively characterized such a novel ORFan-encoded protein, Rki, encoded by the large, virulent enterobacteriaceae bacteriophage RB43. We show that Rki functions to control the host stress-response during the early stages of bacteriophage infection, specifically by interacting with the host DnaK/Hsp70 chaperone to stabilize the major host heat-shock factor, σ32.
Collapse
|
30
|
H11/HspB8 and Its Herpes Simplex Virus Type 2 Homologue ICP10PK Share Functions That Regulate Cell Life/Death Decisions and Human Disease. Autoimmune Dis 2012; 2012:395329. [PMID: 23056924 PMCID: PMC3463903 DOI: 10.1155/2012/395329] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/20/2012] [Accepted: 08/21/2012] [Indexed: 12/24/2022] Open
Abstract
Small heat shock proteins (sHsp) also known as HspB are a large family of widely expressed proteins that contain a 90 residues domain known as α-crystallin. Here, we focus on the family member H11/HspB8 and its herpes simplex virus type 2 (HSV-2) homologue ICP10PK, and discuss the possible impact of this relationship on human disease. H11/HspB8 and ICP10PK are atypical protein kinases. They share multi-functional activity that encompasses signaling, unfolded protein response (UPR) and the regulation of life cycle potential. In melanocytes H11/HspB8 causes growth arrest. It is silenced in a high proportion of melanoma prostate cancer, Ewing's sarcoma and hematologic malignancies through aberrant DNA methylation. Its restored expression induces cell death and inhibits tumor growth in xenograft models, identifying H11/HspB8 as a tumor suppressor. This function involves the activation of multiple and distinct death pathways, all of which initiate with H11/HspB8-mediated phosphorylation of transforming growth factor β-activated kinase 1 (TAK1). Both ICP10PK and H11/HspB8 were implicated in inflammatory processes that involve dendritic cells activation through Toll-like receptor-dependent pathways and may contribute to the onset of autoimmunity. The potential evolutionary relationship of H11/HspB8 to ICP10PK, its impact on human disorders and the development of therapeutic strategies are discussed.
Collapse
|
31
|
Srinivasan SR, Gillies A, Chang L, Thompson AD, Gestwicki JE. Molecular chaperones DnaK and DnaJ share predicted binding sites on most proteins in the E. coli proteome. MOLECULAR BIOSYSTEMS 2012; 8:2323-33. [PMID: 22732719 PMCID: PMC3462289 DOI: 10.1039/c2mb25145k] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In Escherichia coli, the molecular chaperones DnaK and DnaJ cooperate to assist the folding of newly synthesized or unfolded polypeptides. DnaK and DnaJ bind to hydrophobic motifs in these proteins and they also bind to each other. Together, this system is thought to be sufficiently versatile to act on the entire proteome, which creates interesting challenges in understanding the interactions between DnaK, DnaJ and their thousands of potential substrates. To address this question, we computationally predicted the number and frequency of DnaK- and DnaJ-binding motifs in the E. coli proteome, guided by free energy-based binding consensus motifs. This analysis revealed that nearly every protein is predicted to contain multiple DnaK- and DnaJ-binding sites, with the DnaJ sites occurring approximately twice as often. Further, we found that an overwhelming majority of the DnaK sites partially or completely overlapped with the DnaJ-binding motifs. It is well known that high concentrations of DnaJ inhibit DnaK-DnaJ-mediated refolding. The observed overlapping binding sites suggest that this phenomenon may be explained by an important balance in the relative stoichiometry of DnaK and DnaJ. To test this idea, we measured the chaperone-assisted folding of two denatured substrates and found that the distribution of predicted DnaK- and DnaJ-binding sites was indeed a good predictor of the optimal stoichiometry required for folding. These studies provide insight into how DnaK and DnaJ might cooperate to maintain global protein homeostasis.
Collapse
Affiliation(s)
| | - Anne Gillies
- Chemical Biology Graduate Program, University of Michigan Ann Arbor, MI 48109
| | - Lyra Chang
- Chemical Biology Graduate Program, University of Michigan Ann Arbor, MI 48109
| | - Andrea D. Thompson
- Chemical Biology Graduate Program, University of Michigan Ann Arbor, MI 48109
| | - Jason E. Gestwicki
- Chemical Biology Graduate Program, University of Michigan Ann Arbor, MI 48109
- Department of Pathology and Biological Chemistry and the Life Sciences Institute, University of Michigan Ann Arbor, MI 48109
| |
Collapse
|
32
|
Morito D, Nagata K. ER Stress Proteins in Autoimmune and Inflammatory Diseases. Front Immunol 2012; 3:48. [PMID: 22566930 PMCID: PMC3342303 DOI: 10.3389/fimmu.2012.00048] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 02/28/2012] [Indexed: 11/24/2022] Open
Abstract
Over the past two decades, heat shock proteins (HSPs) have been implicated in inflammatory responses and autoimmunity. HSPs were originally believed to maintain protein quality control in the cytosol. However, they also exist extracellularly and appear to act as inflammatory factors. Recently, a growing body of evidence suggested that the other class of stress proteins such as, endoplasmic reticulum (ER) stress proteins, which originally act as protein quality control factors in the secretory pathway and are induced by ER stress in inflammatory lesions, also participate in inflammation and autoimmunity. The immunoglobulin heavy-chain binding protein (Bip)/glucose-regulated protein 78 (GRP78), calnexin, calreticulin, glucose-regulated protein 94 (GRP94)/gp96, oxygen regulated protein 150 (ORP150)/glucose-regulated protein 170 (GRP170), homocysteine-induced ER protein (Herp) and heat shock protein 47 (hsp47)/Serpin H1, which are expressed not only in the ER but also occasionally at the cell surface play pathophysiological roles in autoimmune and inflammatory diseases as pro- or anti-inflammatory factors. Here we describe the accumulating evidence of the participation of ER stress proteins in autoimmunity and inflammation and discuss the critical differences between the two classes of stress proteins.
Collapse
Affiliation(s)
- Daisuke Morito
- Faculty of Life Sciences, Kyoto Sangyo University Kyoto, Japan
| | | |
Collapse
|
33
|
da Silva VCH, Ramos CHI. The network interaction of the human cytosolic 90 kDa heat shock protein Hsp90: A target for cancer therapeutics. J Proteomics 2012; 75:2790-802. [PMID: 22236519 DOI: 10.1016/j.jprot.2011.12.028] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 12/18/2011] [Accepted: 12/19/2011] [Indexed: 10/14/2022]
Abstract
In the cell, proteins interact within a network in which a small number of proteins are highly connected nodes or hubs. A disturbance in the hub proteins usually has a higher impact on the cell physiology than a disturbance in poorly connected nodes. In eukaryotes, the cytosolic Hsp90 is considered to be a hub protein as it interacts with molecular chaperones and co-chaperones, and has key regulatory proteins as clients, such as transcriptional factors, protein kinases and hormone receptors. The large number of Hsp90 partners suggests that Hsp90 is involved in very important functions, such as signaling, proteostasis and epigenetics. Some of these functions are dysregulated in cancer, making Hsp90 a potential target for therapeutics. The number of Hsp90 interactors appears to be so large that a precise answer to the question of how many proteins interact with this chaperone has no definitive answer yet, not even if the question refers to specific Hsp90s as one of the human cytosolic forms. Here we review the major chaperones and co-chaperones that interact with cytosolic Hsp90s, highlighting the latest findings regarding client proteins and the role that posttranslational modifications have on the function and interactions of these molecular chaperones. This article is part of a Special Issue entitled: Proteomics: The clinical link.
Collapse
Affiliation(s)
- Viviane C H da Silva
- Institute of Chemistry, University of Campinas-UNICAMP. P.O. Box 6154, 13083-970, Campinas, SP, Brazil
| | | |
Collapse
|