901
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Using bicistronic constructs to evaluate the chaperone activities of heat shock proteins in cells. Sci Rep 2017; 7:2387. [PMID: 28539657 PMCID: PMC5443837 DOI: 10.1038/s41598-017-02459-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 04/12/2017] [Indexed: 01/03/2023] Open
Abstract
Heat shock proteins (Hsps) are molecular chaperones that prevent the aggregation of client proteins by facilitating their refolding, or trafficking them for degradation. The chaperone activities of Hsps are dependent on dynamic protein-protein interactions, including their oligomerisation into large multi-subunit complexes. Thus, tagging Hsps with fluorescent proteins can interfere with their chaperone activity. To overcome this limitation, we have exploited bicistronic constructs for the concurrent expression of a non-tagged Hsp and fluorescent reporter from a single mRNA in cells. We used the Hsp-encoding bicistronic constructs in a cell-based model of protein aggregation, using a destabilised (mutant) form of firefly luciferase (mFluc) that forms inclusion bodies in cells. Expression of Hsp40, Hsp70, or Hsp40 and Hsp70 in cells expressing mFluc decreased the formation of inclusion bodies by 25–46% compared to controls. Moreover, there was a concentration-dependent decrease in the proportion of cells with inclusions when Hsp70, or Hsp40 and Hsp70 were co-expressed with mFluc in cells. The Hsp-encoding bicistronic constructs enable transfection efficiencies and concentration-dependent effects of Hsp expression to be determined using fluorescence based techniques, without the need to tag the Hsp with a fluorescent protein.
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902
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Sopha P, Ren HY, Grove DE, Cyr DM. Endoplasmic reticulum stress-induced degradation of DNAJB12 stimulates BOK accumulation and primes cancer cells for apoptosis. J Biol Chem 2017; 292:11792-11803. [PMID: 28536268 DOI: 10.1074/jbc.m117.785113] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 05/19/2017] [Indexed: 12/18/2022] Open
Abstract
DNAJB12 (JB12) is an endoplasmic reticulum (ER)-associated Hsp40 family protein that recruits Hsp70 to the ER surface to coordinate the function of ER-associated and cytosolic chaperone systems in protein quality control. Hsp70 is stress-inducible, but paradoxically, we report here that JB12 was degraded by the proteasome during severe ER stress. Destabilized JB12 was degraded by ER-associated degradation complexes that contained HERP, Sel1L, and gp78. JB12 was the only ER-associated chaperone that was destabilized by reductive stress. JB12 knockdown by siRNA led to the induction of caspase processing but not the unfolded protein response. ER stress-induced apoptosis is regulated by the highly labile and ER-associated BCL-2 family member BOK, which is controlled at the level of protein stability by ER-associated degradation components. We found that JB12 was required in human hepatoma cell line 7 (Huh-7) liver cancer cells to maintain BOK at low levels, and BOK was detected in complexes with JB12 and gp78. Depletion of JB12 during reductive stress or by shRNA from Huh-7 cells was associated with accumulation of BOK and activation of Caspase 3, 7, and 9. The absence of JB12 sensitized Huh-7 to death caused by proteotoxic agents and the proapoptotic chemotherapeutic LCL-161. In summary, JB12 is a stress-sensitive Hsp40 whose degradation during severe ER stress provides a mechanism to promote BOK accumulation and induction of apoptosis.
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Affiliation(s)
- Pattarawut Sopha
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599; Program of Applied Biological Sciences, Chulabhorn Graduate Institute, 54 Kamphaeng Phet 6, Talat Bang Khen, Lak Si, Bangkok 10210, Thailand.
| | - Hong Yu Ren
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
| | - Diane E Grove
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
| | - Douglas M Cyr
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599.
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903
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Upadhyay A, Joshi V, Amanullah A, Mishra R, Arora N, Prasad A, Mishra A. E3 Ubiquitin Ligases Neurobiological Mechanisms: Development to Degeneration. Front Mol Neurosci 2017; 10:151. [PMID: 28579943 PMCID: PMC5437216 DOI: 10.3389/fnmol.2017.00151] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/04/2017] [Indexed: 01/08/2023] Open
Abstract
Cells regularly synthesize new proteins to replace old or damaged proteins. Deposition of various aberrant proteins in specific brain regions leads to neurodegeneration and aging. The cellular protein quality control system develop various defense mechanisms against the accumulation of misfolded and aggregated proteins. The mechanisms underlying the selective recognition of specific crucial protein or misfolded proteins are majorly governed by quality control E3 ubiquitin ligases mediated through ubiquitin-proteasome system. Few known E3 ubiquitin ligases have shown prominent neurodevelopmental functions, but their interactions with different developmental proteins play critical roles in neurodevelopmental disorders. Several questions are yet to be understood properly. How E3 ubiquitin ligases determine the specificity and regulate degradation of a particular substrate involved in neuronal proliferation and differentiation is certainly the one, which needs detailed investigations. Another important question is how neurodevelopmental E3 ubiquitin ligases specifically differentiate between their versatile range of substrates and timing of their functional modulations during different phases of development. The premise of this article is to understand how few E3 ubiquitin ligases sense major molecular events, which are crucial for human brain development from its early embryonic stages to throughout adolescence period. A better understanding of these few E3 ubiquitin ligases and their interactions with other potential proteins will provide invaluable insight into disease mechanisms to approach toward therapeutic interventions.
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Affiliation(s)
- Arun Upadhyay
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology JodhpurJodhpur, India
| | - Vibhuti Joshi
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology JodhpurJodhpur, India
| | - Ayeman Amanullah
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology JodhpurJodhpur, India
| | - Ribhav Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology JodhpurJodhpur, India
| | - Naina Arora
- School of Basic Sciences, Indian Institute of Technology MandiMandi, India
| | - Amit Prasad
- School of Basic Sciences, Indian Institute of Technology MandiMandi, India
| | - Amit Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology JodhpurJodhpur, India
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904
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Flagmeier P, De S, Wirthensohn DC, Lee SF, Vincke C, Muyldermans S, Knowles TPJ, Gandhi S, Dobson CM, Klenerman D. Ultrasensitive Measurement of Ca 2+ Influx into Lipid Vesicles Induced by Protein Aggregates. Angew Chem Int Ed Engl 2017; 56:7750-7754. [PMID: 28474754 PMCID: PMC5615231 DOI: 10.1002/anie.201700966] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 03/23/2017] [Indexed: 12/15/2022]
Abstract
To quantify and characterize the potentially toxic protein aggregates associated with neurodegenerative diseases, a high‐throughput assay based on measuring the extent of aggregate‐induced Ca2+ entry into individual lipid vesicles has been developed. This approach was implemented by tethering vesicles containing a Ca2+ sensitive fluorescent dye to a passivated surface and measuring changes in the fluorescence as a result of membrane disruption using total internal reflection microscopy. Picomolar concentrations of Aβ42 oligomers could be observed to induce Ca2+ influx, which could be inhibited by the addition of a naturally occurring chaperone and a nanobody designed to bind to the Aβ peptide. We show that the assay can be used to study aggregates from other proteins, such as α‐synuclein, and to probe the effects of complex biofluids, such as cerebrospinal fluid, and thus has wide applicability.
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Affiliation(s)
- Patrick Flagmeier
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Suman De
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - David C Wirthensohn
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Steven F Lee
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Cécile Vincke
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Serge Muyldermans
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Tuomas P J Knowles
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Sonia Gandhi
- Department of Molecular Neuroscience, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Christopher M Dobson
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - David Klenerman
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
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905
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Sala AJ, Bott LC, Morimoto RI. Shaping proteostasis at the cellular, tissue, and organismal level. J Cell Biol 2017; 216:1231-1241. [PMID: 28400444 PMCID: PMC5412572 DOI: 10.1083/jcb.201612111] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 03/20/2017] [Accepted: 03/20/2017] [Indexed: 01/22/2023] Open
Abstract
The proteostasis network (PN) regulates protein synthesis, folding, transport, and degradation to maintain proteome integrity and limit the accumulation of protein aggregates, a hallmark of aging and degenerative diseases. In multicellular organisms, the PN is regulated at the cellular, tissue, and systemic level to ensure organismal health and longevity. Here we review these three layers of PN regulation and examine how they collectively maintain cellular homeostasis, achieve cell type-specific proteomes, and coordinate proteostasis across tissues. A precise understanding of these layers of control has important implications for organismal health and could offer new therapeutic approaches for neurodegenerative diseases and other chronic disorders related to PN dysfunction.
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Affiliation(s)
- Ambre J Sala
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208
| | - Laura C Bott
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208
| | - Richard I Morimoto
- Department of Molecular Biosciences, Rice Institute for Biomedical Research, Northwestern University, Evanston, IL 60208
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906
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Aivazidis S, Coughlan CM, Rauniyar AK, Jiang H, Liggett LA, Maclean KN, Roede JR. The burden of trisomy 21 disrupts the proteostasis network in Down syndrome. PLoS One 2017; 12:e0176307. [PMID: 28430800 PMCID: PMC5400264 DOI: 10.1371/journal.pone.0176307] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 04/07/2017] [Indexed: 12/27/2022] Open
Abstract
Down syndrome (DS) is a genetic disorder caused by trisomy of chromosome 21. Abnormalities in chromosome number have the potential to lead to disruption of the proteostasis network (PN) and accumulation of misfolded proteins. DS individuals suffer from several comorbidities, and we hypothesized that disruption of proteostasis could contribute to the observed pathology and decreased cell viability in DS. Our results confirm the presence of a disrupted PN in DS, as several of its elements, including the unfolded protein response, chaperone system, and proteasomal degradation exhibited significant alterations compared to euploid controls in both cell and mouse models. Additionally, when cell models were treated with compounds that promote disrupted proteostasis, we observed diminished levels of cell viability in DS compared to controls. Collectively our findings provide a cellular-level characterization of PN dysfunction in DS and an improved understanding of the potential pathogenic mechanisms contributing to disrupted cellular physiology in DS. Lastly, this study highlights the future potential of designing therapeutic strategies that mitigate protein quality control dysfunction.
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Affiliation(s)
- Stefanos Aivazidis
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO, United States of America
| | - Christina M. Coughlan
- Department of Neurology, University of Colorado School of Medicine, Aurora, CO, United States of America
- The Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States of America
| | - Abhishek K. Rauniyar
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO, United States of America
| | - Hua Jiang
- The Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States of America
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, United States of America
| | - L. Alexander Liggett
- The Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States of America
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, United States of America
| | - Kenneth N. Maclean
- The Linda Crnic Institute for Down Syndrome, University of Colorado, Aurora, CO, United States of America
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, United States of America
| | - James R. Roede
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, CO, United States of America
- * E-mail:
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907
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Lai AL, Clerico EM, Blackburn ME, Patel NA, Robinson CV, Borbat PP, Freed JH, Gierasch LM. Key features of an Hsp70 chaperone allosteric landscape revealed by ion-mobility native mass spectrometry and double electron-electron resonance. J Biol Chem 2017; 292:8773-8785. [PMID: 28428246 PMCID: PMC5448104 DOI: 10.1074/jbc.m116.770404] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 04/12/2017] [Indexed: 11/06/2022] Open
Abstract
Proteins are dynamic entities that populate conformational ensembles, and most functions of proteins depend on their dynamic character. Allostery, in particular, relies on ligand-modulated shifts in these conformational ensembles. Hsp70s are allosteric molecular chaperones with conformational landscapes that involve large rearrangements of their two domains (viz. the nucleotide-binding domain and substrate-binding domain) in response to adenine nucleotides and substrates. However, it remains unclear how the Hsp70 conformational ensemble is populated at each point of the allosteric cycle and how ligands control these populations. We have mapped the conformational species present under different ligand-binding conditions throughout the allosteric cycle of the Escherichia coli Hsp70 DnaK by two complementary methods, ion-mobility mass spectrometry and double electron-electron resonance. Our results obtained under biologically relevant ligand-bound conditions confirm the current picture derived from NMR and crystallographic data of domain docking upon ATP binding and undocking in response to ADP and substrate. Additionally, we find that the helical lid of DnaK is a highly dynamic unit of the structure in all ligand-bound states. Importantly, we demonstrate that DnaK populates a partially docked state in the presence of ATP and substrate and that this state represents an energy minimum on the DnaK allosteric landscape. Because Hsp70s are emerging as potential drug targets for many diseases, fully mapping an allosteric landscape of a molecular chaperone like DnaK will facilitate the development of small molecules that modulate Hsp70 function via allosteric mechanisms.
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Affiliation(s)
- Alex L Lai
- From the Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-2703
| | | | - Mandy E Blackburn
- the School of Environmental, Physical, and Applied Sciences, University of Central Missouri, Warrensburg, Missouri 64093, and
| | - Nisha A Patel
- the Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Carol V Robinson
- the Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Peter P Borbat
- From the Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-2703
| | - Jack H Freed
- From the Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-2703
| | - Lila M Gierasch
- the Departments of Biochemistry and Molecular Biology and .,Chemistry, University of Massachusetts, Amherst, Massachusetts 01003
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908
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Sampuda KM, Riley M, Boyd L. Stress induced nuclear granules form in response to accumulation of misfolded proteins in Caenorhabditis elegans. BMC Cell Biol 2017; 18:18. [PMID: 28424053 PMCID: PMC5395811 DOI: 10.1186/s12860-017-0136-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/07/2017] [Indexed: 01/30/2023] Open
Abstract
Background Environmental stress can affect the viability or fecundity of an organism. Environmental stressors may affect the genome or the proteome and can cause cellular distress by contributing to protein damage or misfolding. This study examines the cellular response to environmental stress in the germline of the nematode, C. elegans. Results Salt stress, oxidative stress, and starvation, but not heat shock, induce the relocalization of ubiquitin, proteasome, and the TIAR-2 protein into distinct subnuclear regions referred to as stress induced nuclear granules (SINGs). The SINGs form within 1 h of stress initiation and do not require intertissue signaling. K48-linked polyubiquitin chains but not K63 chains are enriched in SINGs. Worms with a mutation in the conjugating enzyme, ubc-18, do not form SINGs. Additionally, knockdown of ubc-20 and ubc-22 reduces the level of SING formation as does knockdown of the ubiquitin ligase chn-1, a CHIP homolog. The nuclear import machinery is required for SING formation. Stressed embryos containing SINGs fail to hatch and cell division in these embryos is halted. The formation of SINGs can be prevented by pre-exposure to a brief period of heat shock before stress exposure. Heat shock inhibition of SINGs is dependent upon the HSF-1 transcription factor. Conclusions The heat shock results suggest that chaperone expression can prevent SING formation and that the accumulation of damaged or misfolded proteins is a necessary precursor to SING formation. Thus, SINGs may be part of a novel protein quality control system. The data suggest an interesting model where SINGs represent sites of localized protein degradation for nuclear or cytosolic proteins. Thus, the physiological impacts of environmental stress may begin at the cellular level with the formation of stress induced nuclear granules. Electronic supplementary material The online version of this article (doi:10.1186/s12860-017-0136-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Katherine M Sampuda
- Department of Biology, Middle Tennessee State University, 1301 E. Main Street, Murfreesboro, TN, 37132, USA
| | - Mason Riley
- Department of Biology, Middle Tennessee State University, 1301 E. Main Street, Murfreesboro, TN, 37132, USA
| | - Lynn Boyd
- Department of Biology, Middle Tennessee State University, 1301 E. Main Street, Murfreesboro, TN, 37132, USA.
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909
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Jha JK, Li M, Ghirlando R, Miller Jenkins LM, Wlodawer A, Chattoraj D. The DnaK Chaperone Uses Different Mechanisms To Promote and Inhibit Replication of Vibrio cholerae Chromosome 2. mBio 2017; 8:e00427-17. [PMID: 28420739 PMCID: PMC5395669 DOI: 10.1128/mbio.00427-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 03/20/2017] [Indexed: 12/17/2022] Open
Abstract
Replication of Vibrio cholerae chromosome 2 (Chr2) depends on molecular chaperone DnaK to facilitate binding of the initiator (RctB) to the replication origin. The binding occurs at two kinds of site, 12-mers and 39-mers, which promote and inhibit replication, respectively. Here we show that DnaK employs different mechanisms to enhance the two kinds of binding. We found that mutations in rctB that reduce DnaK binding also reduce 12-mer binding and initiation. The initiation defect is suppressed by second-site mutations that increase 12-mer binding only marginally. Instead, they reduce replication inhibitory mechanisms: RctB dimerization and 39-mer binding. One suppressing change was in a dimerization domain which is folded similarly to the initiator of an iteron plasmid-the presumed progenitor of Chr2. In plasmids, DnaK promotes initiation by reducing dimerization. A different mutation was in the 39-mer binding domain of RctB and inactivated it, indicating an alternative suppression mechanism. Paradoxically, although DnaK increases 39-mer binding, the increase was also achieved by inactivating the DnaK binding site of RctB. This result suggests that the site inhibits the 39-mer binding domain (via autoinhibition) when prevented from binding DnaK. Taken together, our results reveal an important feature of the transition from plasmid to chromosome: the Chr2 initiator retains the plasmid-like dimerization domain and its control by chaperones but uses the chaperones in an unprecedented way to control the inhibitory 39-mer binding.IMPORTANCE The capacity of proteins to undergo remodeling provides opportunities to control their function. However, remodeling remains a poorly understood aspect of the structure-function paradigm due to its dynamic nature. Here we have studied remodeling of the initiator of replication of Vibrio cholerae Chr2 by the molecular chaperone, DnaK. We show that DnaK binds to a site on the Chr2 initiator (RctB) that promotes initiation by reducing the initiator's propensity to dimerize. Dimerization of the initiator of the putative plasmid progenitor of Chr2 is also reduced by DnaK, which promotes initiation. Paradoxically, the DnaK binding also promotes replication inhibition by reducing an autoinhibitory activity of RctB. In the plasmid-to-chromosome transition, it appears that the initiator has acquired an autoinhibitory activity and along with it a new chaperone activity that apparently helps to control replication inhibition independently of replication promotion.
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Affiliation(s)
- Jyoti K Jha
- Laboratory of Biochemistry and Molecular Biology, CCR, NCI, NIH, Bethesda, Maryland, USA
| | - Mi Li
- Macromolecular Crystallography Laboratory, NCI, Frederick, Maryland, USA
- Basic Science Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Rodolfo Ghirlando
- Laboratory of Molecular Biology, NIDDK, NIH, Bethesda, Maryland, USA
| | | | - Alexander Wlodawer
- Macromolecular Crystallography Laboratory, NCI, Frederick, Maryland, USA
| | - Dhruba Chattoraj
- Laboratory of Biochemistry and Molecular Biology, CCR, NCI, NIH, Bethesda, Maryland, USA
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910
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Liu F, Qin Y, Yu S, Soares DC, Yang L, Weng J, Li C, Gao M, Lu Z, Hu X, Liu X, Jiang T, Liu JY, Shu X, Tang Z, Liu M. Pathogenic mutations in retinitis pigmentosa 2 predominantly result in loss of RP2 protein stability in humans and zebrafish. J Biol Chem 2017; 292:6225-6239. [PMID: 28209709 PMCID: PMC5391753 DOI: 10.1074/jbc.m116.760314] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 02/14/2017] [Indexed: 12/20/2022] Open
Abstract
Mutations in retinitis pigmentosa 2 (RP2) account for 10-20% of X-linked retinitis pigmentosa (RP) cases. The encoded RP2 protein is implicated in ciliary trafficking of myristoylated and prenylated proteins in photoreceptor cells. To date >70 mutations in RP2 have been identified. How these mutations disrupt the function of RP2 is not fully understood. Here we report a novel in-frame 12-bp deletion (c.357_368del, p.Pro120_Gly123del) in zebrafish rp2 The mutant zebrafish shows reduced rod phototransduction proteins and progressive retinal degeneration. Interestingly, the protein level of mutant Rp2 is almost undetectable, whereas its mRNA level is near normal, indicating a possible post-translational effect of the mutation. Consistent with this hypothesis, the equivalent 12-bp deletion in human RP2 markedly impairs RP2 protein stability and reduces its protein level. Furthermore, we found that a majority of the RP2 pathogenic mutations (including missense, single-residue deletion, and C-terminal truncation mutations) severely destabilize the RP2 protein. The destabilized RP2 mutant proteins are degraded via the proteasome pathway, resulting in dramatically decreased protein levels. The remaining non-destabilizing mutations T87I, R118H/R118G/R118L/R118C, E138G, and R211H/R211L are suggested to impair the interaction between RP2 and its protein partners (such as ARL3) or with as yet unknown partners. By utilizing a combination of in silico, in vitro, and in vivo approaches, our work comprehensively indicates that loss of RP2 protein structural stability is the predominating pathogenic consequence for most RP2 mutations. Our study also reveals a role of the C-terminal domain of RP2 in maintaining the overall protein stability.
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Affiliation(s)
- Fei Liu
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Yayun Qin
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Shanshan Yu
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Dinesh C Soares
- MRC Human Genetics Unit/Centre for Genomic and Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom, and
| | - Lifang Yang
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Jun Weng
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Chang Li
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Meng Gao
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Zhaojing Lu
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Xuebin Hu
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Xiliang Liu
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Tao Jiang
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Jing Yu Liu
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Xinhua Shu
- Department of Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, United Kingdom
| | - Zhaohui Tang
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Mugen Liu
- From the Key Laboratory of Molecular Biophysics of Ministry of Education, Department of Genetics and Developmental Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China,
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911
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Mannini B, Chiti F. Chaperones as Suppressors of Protein Misfolded Oligomer Toxicity. Front Mol Neurosci 2017; 10:98. [PMID: 28424588 PMCID: PMC5380756 DOI: 10.3389/fnmol.2017.00098] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 03/23/2017] [Indexed: 01/30/2023] Open
Abstract
Chaperones have long been recognized to play well defined functions such as to: (i) assist protein folding and promote formation and maintenance of multisubunit complexes; (ii) mediate protein degradation; (iii) inhibit protein aggregation; and (iv) promote disassembly of undesired aberrant protein aggregates. In addition to these well-established functions, it is increasingly clear that chaperones can also interact with aberrant protein aggregates, such as pre-fibrillar oligomers and fibrils, and inhibit their toxicity commonly associated with neurodegenerative diseases without promoting their disassembly. In particular, the evidence collected so far in different labs, exploiting different experimental approaches and using different chaperones and client aggregated proteins, indicates the existence of two distinct mechanisms of action mediated by the chaperones to neutralize the toxicity of aberrant proteins oligomers: (i) direct binding of the chaperones to the hydrophobic patches exposed on the oligomer/fibril surface, with resulting shielding or masking of the moieties responsible for the aberrant interactions with cellular targets; (ii) chaperone-mediated conversion of aberrant protein aggregates into large and more innocuous species, resulting in a decrease of their surface-to-volume ratio and diffusibility and in deposits more easily manageable by clearance mechanisms, such as autophagy. In this review article we will describe the in vitro and in vivo evidence supporting both mechanisms and how this results in a suppression of the detrimental effects caused by protein misfolded aggregates.
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Affiliation(s)
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of FlorenceFlorence, Italy
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912
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Vieira F, Kung JW, Bhatti F. Structure, genetics and function of the pulmonary associated surfactant proteins A and D: The extra-pulmonary role of these C type lectins. Ann Anat 2017; 211:184-201. [PMID: 28351530 DOI: 10.1016/j.aanat.2017.03.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 10/19/2022]
Abstract
The collectins family encompasses several collagenous Ca2+-dependent defense lectins that are described as pathogen recognition molecules. They play an important role in both adaptive and innate immunity. Surfactant proteins A and D are two of these proteins which were initially discovered in association with surfactant in the pulmonary system. The structure, immune and inflammatory functions, and genetic variations have been well described in relation to their roles, function and pathophysiology in the pulmonary system. Subsequently, these proteins have been discovered in a wide range of other organs and organ systems. The role of these proteins outside the pulmonary system is currently an active area of research. This review intends to provide a current overview of the genetics, structure and extra-pulmonary functions of the surfactant collectin proteins.
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Affiliation(s)
- Frederico Vieira
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Johannes W Kung
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Faizah Bhatti
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States; Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States; Oklahoma Center for Neurosciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
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913
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Fu HY, Mukai M, Awata N, Sakata Y, Hori M, Minamino T. Protein Quality Control Dysfunction in Cardiovascular Complications Induced by Anti-Cancer Drugs. Cardiovasc Drugs Ther 2017; 31:109-117. [PMID: 28120277 DOI: 10.1007/s10557-016-6709-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Cardiovascular complications, including heart failure, hypertension, ischemic syndromes and venous thromboembolism, have been identified in patients treated with anti-cancer drugs. Oxidative stress, mitochondrial dysfunction and DNA synthesis inhibition are considered to be responsible for the cardiotoxicity induced by these agents. Protein quality control (PQC) has 3 major components, including the endoplasmic reticulum (ER), the ubiquitin-proteasome system (UPS) and the autophagy-lysosome system, and participates in protein folding and degradation to maintain protein homeostasis. We have demonstrated that PQC dysfunction is a new causal mechanism for the development of cardiac hypertrophy and failure. Increasing evidence shows that anti-cancer drugs, such as tyrosine kinase inhibitors, proteasome inhibitors, anthracyclines and autophagy inhibitors, cause PQC dysfunction. Here, we provide an overview of the potential role of PQC dysfunction in the development of cardiovascular complications induced by anti-cancer drugs.
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Affiliation(s)
- Hai Ying Fu
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.,Department of Clinical Research and Development, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Mikio Mukai
- Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Nobuhisa Awata
- Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Yasushi Sakata
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Masatsugu Hori
- Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Tetsuo Minamino
- Department of Cardiorenal and Cerebrovascular Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Mikicho, Kita-gun, Kagawa Prefecture, 761-0793, Japan.
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914
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Craig EA, Marszalek J. How Do J-Proteins Get Hsp70 to Do So Many Different Things? Trends Biochem Sci 2017; 42:355-368. [PMID: 28314505 DOI: 10.1016/j.tibs.2017.02.007] [Citation(s) in RCA: 130] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 02/09/2017] [Accepted: 02/16/2017] [Indexed: 01/07/2023]
Abstract
Hsp70 chaperone machineries have pivotal roles in an array of fundamental biological processes through their facilitation of protein folding, disaggregation, and remodeling. The obligate J-protein co-chaperones of Hsp70s drive much of this remarkable multifunctionality, with most Hsp70s having multiple J-protein partners. Recent data suggest that J-protein-driven versatility is substantially due to precise localization within the cell and the specificity of substrate protein binding. However, this relatively simple view belies the intricacy of J-protein function. Examples are emerging of J-protein interactions with Hsp70s and other chaperones, as well as integration into broader cellular networks. These interactions fine-tune, in critical ways, the ability of Hsp70s to participate in diverse cellular processes.
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Affiliation(s)
- Elizabeth A Craig
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA.
| | - Jaroslaw Marszalek
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA; Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland.
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915
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916
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Seveso D, Montano S, Reggente MAL, Maggioni D, Orlandi I, Galli P, Vai M. The cellular stress response of the scleractinian coral Goniopora columna during the progression of the black band disease. Cell Stress Chaperones 2017; 22:225-236. [PMID: 27988888 PMCID: PMC5352596 DOI: 10.1007/s12192-016-0756-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/06/2016] [Accepted: 12/07/2016] [Indexed: 12/26/2022] Open
Abstract
Black band disease (BBD) is a widespread coral pathology caused by a microbial consortium dominated by cyanobacteria, which is significantly contributing to the loss of coral cover and diversity worldwide. Since the effects of the BBD pathogens on the physiology and cellular stress response of coral polyps appear almost unknown, the expression of some molecular biomarkers, such as Hsp70, Hsp60, HO-1, and MnSOD, was analyzed in the apparently healthy tissues of Goniopora columna located at different distances from the infection and during two disease development stages. All the biomarkers displayed different levels of expression between healthy and diseased colonies. In the healthy corals, low basal levels were found stable over time in different parts of the same colony. On the contrary, in the diseased colonies, a strong up-regulation of all the biomarkers was observed in all the tissues surrounding the infection, which suffered an oxidative stress probably generated by the alternation, at the progression front of the disease, of conditions of oxygen supersaturation and hypoxia/anoxia, and by the production of the cyanotoxin microcystin by the BBD cyanobacteria. Furthermore, in the infected colonies, the expression of all the biomarkers appeared significantly affected by the development stage of the disease. In conclusion, our approach may constitute a useful diagnostic tool, since the cellular stress response of corals is activated before the pathogens colonize the tissues, and expands the current knowledge of the mechanisms controlling the host responses to infection in corals.
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Affiliation(s)
- Davide Seveso
- Department of Biotechnologies and Biosciences, University of Milano - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy.
- MaRHE Center (Marine Research and High Education Centre), Magoodhoo Island, Faafu Atoll, Republic of Maldives.
| | - Simone Montano
- Department of Biotechnologies and Biosciences, University of Milano - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
- MaRHE Center (Marine Research and High Education Centre), Magoodhoo Island, Faafu Atoll, Republic of Maldives
| | - Melissa Amanda Ljubica Reggente
- Department of Biotechnologies and Biosciences, University of Milano - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
- MaRHE Center (Marine Research and High Education Centre), Magoodhoo Island, Faafu Atoll, Republic of Maldives
| | - Davide Maggioni
- Department of Biotechnologies and Biosciences, University of Milano - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
- MaRHE Center (Marine Research and High Education Centre), Magoodhoo Island, Faafu Atoll, Republic of Maldives
| | - Ivan Orlandi
- Department of Biotechnologies and Biosciences, University of Milano - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
| | - Paolo Galli
- Department of Biotechnologies and Biosciences, University of Milano - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
- MaRHE Center (Marine Research and High Education Centre), Magoodhoo Island, Faafu Atoll, Republic of Maldives
| | - Marina Vai
- Department of Biotechnologies and Biosciences, University of Milano - Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
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917
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McMurray MA. Coupling de novo protein folding with subunit exchange into pre-formed oligomeric protein complexes: the 'heritable template' hypothesis. Biomol Concepts 2017; 7:271-281. [PMID: 27875316 DOI: 10.1515/bmc-2016-0023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 10/11/2016] [Indexed: 11/15/2022] Open
Abstract
Despite remarkable advances in synthetic biology, the fact remains that it takes a living cell to make a new living cell. The information encoded in the genome is necessary to direct assembly of all cellular components, but it may not be sufficient. Some components (e.g. mitochondria) cannot be synthesized de novo, and instead require pre-existing templates, creating a fundamental continuity of life: if the template information is ever lost, the genomic code cannot suffice to ensure proper biogenesis. One type of information only incompletely encoded in the genome is the structures of macromolecular assemblies, which emerge from the conformations of the constituent molecules coupled with the ways in which these molecules interact. For many, if not most proteins, gene sequence is not the sole determinant of native conformation, particularly in the crowded cellular milieu. A partial solution to this problem lies in the functions of molecular chaperones, encoded by nearly all cellular genomes. Chaperones effectively restrict the ensemble of conformations sampled by polypeptides, promoting the acquisition of native, functional forms, but multiple proteins have evolved ways to achieve chaperone independence, perhaps by coupling folding with higher-order assembly. Here, I propose the existence of another solution: a novel mechanism of de novo folding in which the folding of specific proteins is templated by pre-folded molecules of a partner protein whose own folding also required similar templating. This hypothesis challenges prevailing paradigms by predicting that, in order to achieve a functional fold, some non-prion proteins require a seed passed down through generations.
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918
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Hill SM, Hanzén S, Nyström T. Restricted access: spatial sequestration of damaged proteins during stress and aging. EMBO Rep 2017; 18:377-391. [PMID: 28193623 PMCID: PMC5331209 DOI: 10.15252/embr.201643458] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 12/19/2016] [Accepted: 01/24/2017] [Indexed: 01/08/2023] Open
Abstract
The accumulation of damaged and aggregated proteins is a hallmark of aging and increased proteotoxic stress. To limit the toxicity of damaged and aggregated proteins and to ensure that the damage is not inherited by succeeding cell generations, a system of spatial quality control operates to sequester damaged/aggregated proteins into inclusions at specific protective sites. Such spatial sequestration and asymmetric segregation of damaged proteins have emerged as key processes required for cellular rejuvenation. In this review, we summarize findings on the nature of the different quality control sites identified in yeast, on genetic determinants required for spatial quality control, and on how aggregates are recognized depending on the stress generating them. We also briefly compare the yeast system to spatial quality control in other organisms. The data accumulated demonstrate that spatial quality control involves factors beyond the canonical quality control factors, such as chaperones and proteases, and opens up new venues in approaching how proteotoxicity might be mitigated, or delayed, upon aging.
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Affiliation(s)
- Sandra Malmgren Hill
- Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden
| | - Sarah Hanzén
- Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden
| | - Thomas Nyström
- Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden
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919
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Imaging and Force Recognition of Single Molecular Behaviors Using Atomic Force Microscopy. SENSORS 2017; 17:s17010200. [PMID: 28117741 PMCID: PMC5298773 DOI: 10.3390/s17010200] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 01/12/2017] [Accepted: 01/16/2017] [Indexed: 12/23/2022]
Abstract
The advent of atomic force microscopy (AFM) has provided a powerful tool for investigating the behaviors of single native biological molecules under physiological conditions. AFM can not only image the conformational changes of single biological molecules at work with sub-nanometer resolution, but also sense the specific interactions of individual molecular pair with piconewton force sensitivity. In the past decade, the performance of AFM has been greatly improved, which makes it widely used in biology to address diverse biomedical issues. Characterizing the behaviors of single molecules by AFM provides considerable novel insights into the underlying mechanisms guiding life activities, contributing much to cell and molecular biology. In this article, we review the recent developments of AFM studies in single-molecule assay. The related techniques involved in AFM single-molecule assay were firstly presented, and then the progress in several aspects (including molecular imaging, molecular mechanics, molecular recognition, and molecular activities on cell surface) was summarized. The challenges and future directions were also discussed.
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920
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Vonk JJ, Yeshaw WM, Pinto F, Faber AIE, Lahaye LL, Kanon B, van der Zwaag M, Velayos-Baeza A, Freire R, van IJzendoorn SC, Grzeschik NA, Sibon OCM. Drosophila Vps13 Is Required for Protein Homeostasis in the Brain. PLoS One 2017; 12:e0170106. [PMID: 28107480 PMCID: PMC5249141 DOI: 10.1371/journal.pone.0170106] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 12/10/2016] [Indexed: 11/22/2022] Open
Abstract
Chorea-Acanthocytosis is a rare, neurodegenerative disorder characterized by progressive loss of locomotor and cognitive function. It is caused by loss of function mutations in the Vacuolar Protein Sorting 13A (VPS13A) gene, which is conserved from yeast to human. The consequences of VPS13A dysfunction in the nervous system are still largely unspecified. In order to study the consequences of VPS13A protein dysfunction in the ageing central nervous system we characterized a Drosophila melanogaster Vps13 mutant line. The Drosophila Vps13 gene encoded a protein of similar size as human VPS13A. Our data suggest that Vps13 is a peripheral membrane protein located to endosomal membranes and enriched in the fly head. Vps13 mutant flies showed a shortened life span and age associated neurodegeneration. Vps13 mutant flies were sensitive to proteotoxic stress and accumulated ubiquitylated proteins. Levels of Ref(2)P, the Drosophila orthologue of p62, were increased and protein aggregates accumulated in the central nervous system. Overexpression of the human Vps13A protein in the mutant flies partly rescued apparent phenotypes. This suggests a functional conservation of human VPS13A and Drosophila Vps13. Our results demonstrate that Vps13 is essential to maintain protein homeostasis in the larval and adult Drosophila brain. Drosophila Vps13 mutants are suitable to investigate the function of Vps13 in the brain, to identify genetic enhancers and suppressors and to screen for potential therapeutic targets for Chorea-Acanthocytosis.
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Affiliation(s)
- Jan J. Vonk
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Wondwossen M. Yeshaw
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Francesco Pinto
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Anita I. E. Faber
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Liza L. Lahaye
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Bart Kanon
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Marianne van der Zwaag
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | | | - Raimundo Freire
- Unidad de Investigación, Hospital Universitario de Canarias, Instituto de Tecnologías Biomédicas, Ofra s/n, La Laguna, Tenerife, Spain
| | - Sven C. van IJzendoorn
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Nicola A. Grzeschik
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Ody C. M. Sibon
- Department of Cell Biology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- * E-mail:
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921
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Oya Y, Mondal A, Rawangkan A, Umsumarng S, Iida K, Watanabe T, Kanno M, Suzuki K, Li Z, Kagechika H, Shudo K, Fujiki H, Suganuma M. Down-regulation of histone deacetylase 4, -5 and -6 as a mechanism of synergistic enhancement of apoptosis in human lung cancer cells treated with the combination of a synthetic retinoid, Am80 and green tea catechin. J Nutr Biochem 2017; 42:7-16. [PMID: 28103535 DOI: 10.1016/j.jnutbio.2016.12.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Revised: 12/15/2016] [Accepted: 12/31/2016] [Indexed: 01/26/2023]
Abstract
(-)-Epigallocatechin gallate (EGCG), a green tea catechin, acts as a synergist with various anticancer drugs, including retinoids. Am80 is a synthetic retinoid with a different structure from all-trans-retinoic acid: Am80 is now clinically utilized as a new drug for relapsed and intractable acute promyelocytic leukemia patients. Our experiments showed that the combination of EGCG and Am80 synergistically induced both apoptosis in human lung cancer cell line PC-9 and up-regulated expressions of growth arrest and DNA damage-inducible gene 153 (GADD153), death receptor 5, and p21waf1 genes in the cells. To understand the mechanisms of synergistic anticancer activity of the combination, we gave special attention to the lysine acetylation of proteins. Proteomic analysis using nanoLC-ESI-MS/MS revealed that PC-9 cells treated with the combination contained 331 acetylated proteins, while nontreated cells contained 553 acetylated proteins, and 59 acetylated proteins were found in both groups. Among them, the combination increased acetylated-p53 and acetylated-α-tubulin through reduction of histone deacetylase (HDAC) activity in cytosol fraction, although the levels of acetylation in histones H3 or H4 did not change, and the combination reduced protein levels of HDAC4, -5 and -6 by 20% to 80%. Moreover, we found that a specific inhibitor of HDAC4 and -5 strongly induced p21waf1 gene expression, and that of HDAC6 induced both GADD153 and p21waf1 gene expression, which resulted in apoptosis. All results demonstrate that EGCG in combination with Am80 changes levels of acetylation in nonhistone proteins via down-regulation of HDAC4, -5 and -6 and stimulates apoptotic induction.
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Affiliation(s)
- Yukiko Oya
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
| | - Anupom Mondal
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
| | - Anchalee Rawangkan
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
| | - Sonthaya Umsumarng
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
| | - Keisuke Iida
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
| | - Tatsuro Watanabe
- Faculty of Medicine, Saga University, Nabeshima, Saga 849-8501, Japan.
| | - Miki Kanno
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
| | - Kaori Suzuki
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
| | - Zhenghao Li
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
| | - Hiroyuki Kagechika
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU), Tokyo 101-0062, Japan.
| | - Koichi Shudo
- Japan Pharmaceutical Information Center, Shibuya, Tokyo 150-0002, Japan.
| | - Hirota Fujiki
- Faculty of Medicine, Saga University, Nabeshima, Saga 849-8501, Japan.
| | - Masami Suganuma
- Graduate School of Science and Engineering, Saitama University, Shimo-okubo 255, Sakura-ku, Saitama, Saitama 338-8570, Japan; Research Institute for Clinical Oncology, Saitama Cancer Center, Ina, Kitaadachi-gun, Saitama 362-0806, Japan.
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922
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Sluchanko NN, Gusev NB. Moonlighting chaperone‐like activity of the universal regulatory 14‐3‐3 proteins. FEBS J 2017; 284:1279-1295. [DOI: 10.1111/febs.13986] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 11/20/2016] [Accepted: 12/06/2016] [Indexed: 12/25/2022]
Affiliation(s)
- Nikolai N. Sluchanko
- Laboratory of Structural Biochemistry of Proteins A. N. Bach Institute of Biochemistry Federal Research Center of Biotechnology of the Russian Academy of Sciences Moscow Russia
| | - Nikolai B. Gusev
- Department of Biochemistry School of Biology Moscow State University Russia
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923
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CK2-An Emerging Target for Neurological and Psychiatric Disorders. Pharmaceuticals (Basel) 2017; 10:ph10010007. [PMID: 28067771 PMCID: PMC5374411 DOI: 10.3390/ph10010007] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 12/20/2016] [Accepted: 12/30/2016] [Indexed: 12/16/2022] Open
Abstract
Protein kinase CK2 has received a surge of attention in recent years due to the evidence of its overexpression in a variety of solid tumors and multiple myelomas as well as its participation in cell survival pathways. CK2 is also upregulated in the most prevalent and aggressive cancer of brain tissue, glioblastoma multiforme, and in preclinical models, pharmacological inhibition of the kinase has proven successful in reducing tumor size and animal mortality. CK2 is highly expressed in the mammalian brain and has many bona fide substrates that are crucial in neuronal or glial homeostasis and signaling processes across synapses. Full and conditional CK2 knockout mice have further elucidated the importance of CK2 in brain development, neuronal activity, and behavior. This review will discuss recent advances in the field that point to CK2 as a regulator of neuronal functions and as a potential novel target to treat neurological and psychiatric disorders.
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924
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Klimek C, Kathage B, Wördehoff J, Höhfeld J. BAG3-mediated proteostasis at a glance. J Cell Sci 2017; 130:2781-2788. [DOI: 10.1242/jcs.203679] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
ABSTRACT
Cellular and organismal survival depend on the ability to maintain the proteome, even under conditions that threaten protein integrity. BCL2-associated athanogene 3 (BAG3) is essential for protein homeostasis (proteostasis) in stressed cells. Owing to its multi-domain structure, it engages in diverse processes that are crucial for proteome maintenance. BAG3 promotes the activity of molecular chaperones, sequesters and concentrates misfolded proteins, initiates autophagic disposal, and balances transcription, translation and degradation. In this Cell Science at a Glance article and the accompanying poster, we discuss the functions of this multi-functional proteostasis tool with a focus on mechanical stress protection and describe the importance of BAG3 for human physiology and pathophysiology.
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Affiliation(s)
- Christina Klimek
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, D-53121 Bonn, Germany
| | - Barbara Kathage
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, D-53121 Bonn, Germany
| | - Judith Wördehoff
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, D-53121 Bonn, Germany
| | - Jörg Höhfeld
- Institute for Cell Biology, University of Bonn, Ulrich-Haberland-Str. 61a, D-53121 Bonn, Germany
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925
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Inada T. The Ribosome as a Platform for mRNA and Nascent Polypeptide Quality Control. Trends Biochem Sci 2017; 42:5-15. [DOI: 10.1016/j.tibs.2016.09.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 09/05/2016] [Accepted: 09/13/2016] [Indexed: 11/28/2022]
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926
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Heat Shock Protein A2 (HSPA2): Regulatory Roles in Germ Cell Development and Sperm Function. ADVANCES IN ANATOMY, EMBRYOLOGY, AND CELL BIOLOGY 2017; 222:67-93. [PMID: 28389751 DOI: 10.1007/978-3-319-51409-3_4] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Among the numerous families of heat shock protein (HSP) that have been implicated in the regulation of reproductive system development and function, those belonging to the 70 kDa HSP family have emerged as being indispensable for male fertility. In particular, the testis-enriched heat shock 70 kDa protein 2 (HSPA2) has been shown to be critical for the progression of germ cell differentiation during spermatogenesis in the mouse model. Beyond this developmentally important window, mounting evidence has also implicated HSPA2 in the functional transformation of the human sperm cell during their ascent of the female reproductive tract. Specifically, HSPA2 appears to coordinate the remodelling of specialised sperm domains overlying the anterior region of the sperm head compatible with their principle role in oocyte recognition. The fact that levels of the HSPA2 protein in mature spermatozoa tightly correlate with the efficacy of oocyte binding highlight its utility as a powerful prognostic biomarker of male fertility. In this chapter, we consider the unique structural and biochemical characteristics of HSPA2 that enable this heat shock protein to fulfil its prominent roles in orchestrating the morphological differentiation of male germ cells during spermatogenesis as well as their functional transformation during post-testicular sperm maturation.
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927
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The Endoplasmic Reticulum and the Cellular Reticular Network. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 981:61-76. [DOI: 10.1007/978-3-319-55858-5_4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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928
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Theocharopoulou G, Bobori C, Vlamos P. Formal Models of Biological Systems. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 988:325-338. [PMID: 28971411 DOI: 10.1007/978-3-319-56246-9_27] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Recent biomedical research studies are focused in the mechanisms by which misfolded proteins lead to the generation of oxidative stress in the form of reactive oxygen species (ROS), often implicated in neurodegenerative diseases and aging. Moreover, biological experiments are designed to investigate how proteostasis depends on the balance between the folding capacity of chaperone networks and the continuous flux of potentially nonnative proteins. Nevertheless, biological experimental methods can examine the protein folding quality control mechanisms only in individual cells, but not in a multicellular level. Formal models offer a dynamic form of modelling, which allows to explore various parameter values in an integrated time-dependent system. This paper aims to present a formal approach of a mathematical descriptive model using as example a representation of a known molecular chaperone system and its relation to diseases associated to protein misfolding and neurodegeneration.
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Affiliation(s)
| | | | - Panayiotis Vlamos
- Department of Informatics, Bioinformatics and Human Electrophysiology Laboratory, Ionian University, Corfu, Greece
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929
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Rinaldi C, Mäger I, Wood MJ. Proteostasis and Diseases of the Motor Unit. Front Mol Neurosci 2016; 9:164. [PMID: 28082869 PMCID: PMC5187379 DOI: 10.3389/fnmol.2016.00164] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 12/19/2016] [Indexed: 12/12/2022] Open
Abstract
The accumulation in neurons of aberrant protein species, the pathological hallmark of many neurodegenerative diseases, results from a global impairment of key cellular processes governing protein synthesis/degradation and repair mechanisms, also known as the proteostasis network (PN). The growing number of connections between dysfunction of this intricate network of pathways and diseases of the motor unit, where both motor neurons and muscle are primarily affected, has provided momentum to investigate the muscle- and motor neuron-specific response to physiological and pathological stressors and to explore the therapeutic opportunities that manipulation of this process may offer. Furthermore, these diseases offer an unparalleled opportunity to deepen our understanding of the molecular mechanisms behind the intertissue communication and transfer of signals of proteostasis. The most compelling aspect of these investigations is their immediate potential for therapeutic impact: targeting muscle to stem degeneration of the motor unit would represent a dramatic paradigm therapeutic shift for treating these devastating diseases. Here we will review the current state of the art of the research on the alterations of the PN in diseases of the motor unit and its potential to result in effective treatments for these devastating neuromuscular disorders.
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Affiliation(s)
- Carlo Rinaldi
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
| | - Imre Mäger
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
| | - Matthew J Wood
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
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930
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Afolayan AJ, Alexander M, Holme RL, Michalkiewicz T, Rana U, Teng RJ, Zemanovic S, Sahoo D, Pritchard KA, Konduri GG. Domain Mapping of Heat Shock Protein 70 Reveals That Glutamic Acid 446 and Arginine 447 Are Critical for Regulating Superoxide Dismutase 2 Function. J Biol Chem 2016; 292:2369-2378. [PMID: 28028182 DOI: 10.1074/jbc.m116.756122] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 12/19/2016] [Indexed: 12/15/2022] Open
Abstract
Stress-inducible heat shock protein 70 (hsp70) interacts with superoxide dismutase 2 (SOD2) in the cytosol after synthesis to transfer the enzyme to the mitochondria for subsequent activation. However, the structural basis for this interaction remains to be defined. To map the SOD2-binding site in hsp70, mutants of hsp70 were made and tested for their ability to bind SOD2. These studies showed that SOD2 binds in the amino acid 393-537 region of the chaperone. To map the hsp70-binding site in SOD2, we used a series of pulldown assays and showed that hsp70 binds to the amino-terminal domain of SOD2. To better define the binding site, we used a series of decoy peptides derived from the primary amino acid sequence in the SOD2-binding site in hsp70. This study shows that SOD2 specifically binds to hsp70 at 445GERAMT450 Small peptides containing GERAMT inhibited the transfer of SOD2 to the mitochondria and decreased SOD2 activity in vitro and in vivo To determine the amino acid residues in hsp70 that are critical for SOD2 interactions, we substituted each amino acid residue for alanine or more conservative residues, glutamine or asparagine, in the GERAMT-binding site. Substitutions of E446A/Q and R447A/Q inhibited the ability of the GERAMT peptide to bind SOD2 and preserved SOD2 function more than other substitutions. Together, these findings indicate that the GERAMT sequence is critical for hsp70-mediated regulation of SOD2 and that Glu446 and Arg447 cooperate with other amino acid residues in the GERAMT-binding site for proper chaperone-dependent regulation of SOD2 antioxidant function.
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Affiliation(s)
- Adeleye J Afolayan
- From the Department of Pediatrics, Cardiovascular Research Center, .,Children's Research Institute
| | - Maxwell Alexander
- From the Department of Pediatrics, Cardiovascular Research Center.,Children's Research Institute
| | - Rebecca L Holme
- Children's Research Institute.,Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Teresa Michalkiewicz
- From the Department of Pediatrics, Cardiovascular Research Center.,Children's Research Institute
| | - Ujala Rana
- From the Department of Pediatrics, Cardiovascular Research Center.,Children's Research Institute
| | - Ru-Jeng Teng
- From the Department of Pediatrics, Cardiovascular Research Center.,Children's Research Institute
| | - Sara Zemanovic
- From the Department of Pediatrics, Cardiovascular Research Center.,Children's Research Institute
| | - Daisy Sahoo
- Children's Research Institute.,Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin 53226
| | - Kirkwood A Pritchard
- Children's Research Institute.,Department of Surgery, Division of Pediatric Surgery, and
| | - Girija G Konduri
- From the Department of Pediatrics, Cardiovascular Research Center.,Children's Research Institute
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931
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Interaction of E. coli Hsp90 with DnaK Involves the DnaJ Binding Region of DnaK. J Mol Biol 2016; 429:858-872. [PMID: 28013030 DOI: 10.1016/j.jmb.2016.12.014] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 12/13/2016] [Accepted: 12/15/2016] [Indexed: 01/05/2023]
Abstract
The 90-kDa heat shock protein (Hsp90) is a widely conserved and ubiquitous molecular chaperone that participates in ATP-dependent protein remodeling in both eukaryotes and prokaryotes. It functions in conjunction with Hsp70 and the Hsp70 cochaperones, an Hsp40 (J-protein) and a nucleotide exchange factor. In Escherichia coli, the functional collaboration between Hsp90Ec and Hsp70, DnaK, requires that the two chaperones directly interact. We used molecular docking to model the interaction of Hsp90Ec and DnaK. The top-ranked docked model predicted that a region in the nucleotide-binding domain (NBD) of DnaK interacted with a region in the middle domain of Hsp90Ec. We then made substitution mutants in DnaK residues suggested by the model to interact with Hsp90Ec. Of the 12 mutants tested, 11 were defective or partially defective in their ability to interact with Hsp90Ecin vivo in a bacterial two-hybrid assay and in vitro in a bio-layer interferometry assay. These DnaK mutants were also defective in their ability to function collaboratively in protein remodeling with Hsp90Ec but retained the ability to act with DnaK cochaperones. Taken together, these results suggest that a specific region in the NBD of DnaK is involved in the interaction with Hsp90Ec, and this interaction is functionally important. Moreover, the region of DnaK that we found to be necessary for Hsp90Ec binding includes residues that are also involved in J-protein binding, suggesting a functional interplay among DnaK, DnaK cochaperones, and Hsp90Ec.
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932
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Affiliation(s)
- Christopher A Ross
- Departments of Psychiatry, Neurology, Neuroscience and Pharmacology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Ray Truant
- Departments of Psychiatry, Neurology, Neuroscience and Pharmacology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
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933
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Thommen M, Holtkamp W, Rodnina MV. Co-translational protein folding: progress and methods. Curr Opin Struct Biol 2016; 42:83-89. [PMID: 27940242 DOI: 10.1016/j.sbi.2016.11.020] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 11/22/2016] [Indexed: 11/19/2022]
Abstract
Proteins are synthesized as linear polymers and have to fold into their native structure to fulfil various functions in the cell. Folding can start co-translationally when the emerging peptide is still attached to the ribosome and is guided by the environment of the polypeptide exit tunnel and the kinetics of translation. Major questions are: When does co-translational folding begin? What is the role of the ribosome in guiding the nascent peptide towards its native structure? How does translation elongation kinetics modulate protein folding? Here we suggest how novel structural and biophysical approaches can help to probe the interplay between the ribosome and the emerging peptide and present future challenges in understanding co-translational folding.
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Affiliation(s)
- Michael Thommen
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Goettingen 37077, Germany
| | - Wolf Holtkamp
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Goettingen 37077, Germany
| | - Marina V Rodnina
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Goettingen 37077, Germany.
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934
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Reconstitution of a Mycobacterium tuberculosis proteostasis network highlights essential cofactor interactions with chaperone DnaK. Proc Natl Acad Sci U S A 2016; 113:E7947-E7956. [PMID: 27872278 DOI: 10.1073/pnas.1617644113] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During host infection, Mycobacterium tuberculosis (Mtb) encounters several types of stress that impair protein integrity, including reactive oxygen and nitrogen species and chemotherapy. The resulting protein aggregates can be resolved or degraded by molecular machinery conserved from bacteria to eukaryotes. Eukaryotic Hsp104/Hsp70 and their bacterial homologs ClpB/DnaK are ATP-powered chaperones that restore toxic protein aggregates to a native folded state. DnaK is essential in Mycobacterium smegmatis, and ClpB is involved in asymmetrically distributing damaged proteins during cell division as a mechanism of survival in Mtb, commending both proteins as potential drug targets. However, their molecular partners in protein reactivation have not been characterized in mycobacteria. Here, we reconstituted the activities of the Mtb ClpB/DnaK bichaperone system with the cofactors DnaJ1, DnaJ2, and GrpE and the small heat shock protein Hsp20. We found that DnaJ1 and DnaJ2 activate the ATPase activity of DnaK differently. A point mutation in the highly conserved HPD motif of the DnaJ proteins abrogates their ability to activate DnaK, although the DnaJ2 mutant still binds to DnaK. The purified Mtb ClpB/DnaK system reactivated a heat-denatured model substrate, but the DnaJ HPD mutants inhibited the reaction. Finally, either DnaJ1 or DnaJ2 is required for mycobacterial viability, as is the DnaK-activating activity of a DnaJ protein. These studies lay the groundwork for strategies to target essential chaperone-protein interactions in Mtb, the leading cause of death from a bacterial infection.
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935
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Quality control of glycoprotein folding and ERAD: the role of N-glycan handling, EDEM1 and OS-9. Histochem Cell Biol 2016; 147:269-284. [DOI: 10.1007/s00418-016-1513-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/20/2016] [Indexed: 02/03/2023]
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936
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Araki K, Suenaga A, Kusano H, Tanaka R, Hatta T, Natsume T, Fukui K. Functional profiling of asymmetrically-organized human CCT/TRiC chaperonin. Biochem Biophys Res Commun 2016; 481:232-238. [PMID: 27806916 DOI: 10.1016/j.bbrc.2016.10.120] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 10/27/2016] [Indexed: 12/25/2022]
Abstract
Molecular organization of the eukaryote chaperonin known as CCT/TRiC complex was recently clarified. Eight distinct subunits are uniquely organized, providing a favorable folding cavity for specific client proteins such as tubulin and actin. Because of its heterogeneous subunit composition, CCT complex has polarized inner faces, which may underlie an essential part of its chaperonin function. In this study, we structurally characterized the closed and open states of CCT complex, using molecular dynamics analyses. Our results showed that the inter-subunit interaction energies were asymmetrically distributed and were remodeled during conformational changes of CCT complex. In addition, exploration of redox related characteristics indicated changes in inner surface properties, including electrostatic potential, pKa and exposure of inner cysteine thiol groups, between the closed and open states. Cysteine activation events were experimentally verified by interaction analyses, using tubulin as a model substrate. Our data highlighted the importance of dynamics-based structural profiling of asymmetrically oriented chaperonin function.
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Affiliation(s)
- Kazutaka Araki
- Molecular Profiling Research Center for Drug Discovery, National Institute of Advanced Industrial Science and Technology, Tokyo 135-0064, Japan.
| | - Atsushi Suenaga
- Molecular Profiling Research Center for Drug Discovery, National Institute of Advanced Industrial Science and Technology, Tokyo 135-0064, Japan; Department of Biosciences, College of Humanities and Sciences, Nihon University, 3-25-40 Sakurajosui Setagaya-Ku, Tokyo 156-8550, Japan
| | - Hidewo Kusano
- Molecular Profiling Research Center for Drug Discovery, National Institute of Advanced Industrial Science and Technology, Tokyo 135-0064, Japan
| | - Riko Tanaka
- Molecular Profiling Research Center for Drug Discovery, National Institute of Advanced Industrial Science and Technology, Tokyo 135-0064, Japan
| | | | - Tohru Natsume
- Molecular Profiling Research Center for Drug Discovery, National Institute of Advanced Industrial Science and Technology, Tokyo 135-0064, Japan; Robotic Biology Institute, Inc., Tokyo 135-0064, Japan
| | - Kazuhiko Fukui
- Molecular Profiling Research Center for Drug Discovery, National Institute of Advanced Industrial Science and Technology, Tokyo 135-0064, Japan.
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937
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Affiliation(s)
- Qinglian Liu
- Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, Virginia 23298-0551, USA
| | - Elizabeth A Craig
- Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, Virginia 23298-0551, USA
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938
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Zang Y, Jin M, Wang H, Cui Z, Kong L, Liu C, Cong Y. Staggered ATP binding mechanism of eukaryotic chaperonin TRiC (CCT) revealed through high-resolution cryo-EM. Nat Struct Mol Biol 2016; 23:1083-1091. [PMID: 27775711 DOI: 10.1038/nsmb.3309] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 09/20/2016] [Indexed: 01/04/2023]
Abstract
The eukaryotic chaperonin TRiC (or CCT) assists in the folding of 10% of cytosolic proteins. Here we present two cryo-EM structures of Saccharomyces cerevisiae TRiC in a newly identified nucleotide partially preloaded (NPP) state and in the ATP-bound state, at 4.7-Å and 4.6-Å resolution, respectively. Through inner-subunit eGFP tagging, we identified the subunit locations in open-state TRiC and found that the CCT2 subunit pair forms an unexpected Z shape. ATP binding induces a dramatic conformational change on the CCT2 side, thereby suggesting that CCT2 plays an essential role in TRiC allosteric cooperativity. Our structural and biochemical data reveal a staggered ATP binding mechanism of TRiC with preloaded nucleotide on the CCT6 side of NPP-TRiC and demonstrate that TRiC has evolved into a complex that is structurally divided into two sides. This work offers insight into how the TRiC nucleotide cycle coordinates with its mechanical cycle in preparing folding intermediates for further productive folding.
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Affiliation(s)
- Yunxiang Zang
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Mingliang Jin
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Huping Wang
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Zhicheng Cui
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Liangliang Kong
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,Shanghai Science Research Center, Chinese Academy of Sciences, Shanghai, China
| | - Caixuan Liu
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yao Cong
- National Center for Protein Science Shanghai, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,Shanghai Science Research Center, Chinese Academy of Sciences, Shanghai, China
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939
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Krzemień-Ojak Ł, Góral A, Joachimiak E, Filipek A, Fabczak H. Interaction of a Novel Chaperone PhLP2A With the Heat Shock Protein Hsp90. J Cell Biochem 2016; 118:420-429. [PMID: 27496612 DOI: 10.1002/jcb.25669] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 08/04/2016] [Indexed: 01/23/2023]
Abstract
PhLP2 is a small cytosolic protein that belongs to the highly conserved phosducin-like family of proteins. In amniote genomes there are two PhLP2 homologs, PhLP2A and PhLP2B. It has been shown that mammalian PhLP2A modulates the CCT/TRiC chaperonin activity during folding of cytoskeletal proteins. In order to better understand the function of PhLP2A in cellular protein quality control system, in the present study we have searched for its protein targets. Applying immunoprecipitation followed by mass spectrometry analysis we have identified Hsp90 as a partner of PhLP2A. With pull down experiments, we have confirmed this interaction in protein lysate and using purified proteins we have shown that PhLP2A interacts directly with Hsp90. Furthermore, the proximity ligation assay (PLA) performed on mIMCD-3 cells has shown that PhLP2A forms complexes with Hsp90 which are mainly localized in the cytoplasm of these cells. Further analysis has indicated that the level of PhLP2A increases after heat shock or radicicol treatment, similarly as the level of Hsp90, and that expression of PhLP2A after heat shock is regulated at the transcriptional level. Moreover, using recombinant luciferase we have shown that PhLP2A stabilizes this enzyme in a folding competent state and prevents its denaturation and aggregation. In addition, overexpression of PhLP2A in HEK-293 cells leads to increased heat stress resistance. Altogether, our results have shown that PhLP2A interacts with Hsp90 and exhibits molecular chaperone activity toward denatured proteins. J. Cell. Biochem. 118: 420-429, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Łucja Krzemień-Ojak
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, Warsaw, 02-093, Poland
| | - Agnieszka Góral
- Laboratory of Calcium Binding Proteins, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, Warsaw, 02-093, Poland
| | - Ewa Joachimiak
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, Warsaw, 02-093, Poland
| | - Anna Filipek
- Laboratory of Calcium Binding Proteins, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, Warsaw, 02-093, Poland
| | - Hanna Fabczak
- Laboratory of Cytoskeleton and Cilia Biology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur Street, Warsaw, 02-093, Poland
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940
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Rodina A, Wang T, Yan P, Gomes ED, Dunphy MPS, Pillarsetty N, Koren J, Gerecitano JF, Taldone T, Zong H, Caldas-Lopes E, Alpaugh M, Corben A, Riolo M, Beattie B, Pressl C, Peter RI, Xu C, Trondl R, Patel HJ, Shimizu F, Bolaender A, Yang C, Panchal P, Farooq MF, Kishinevsky S, Modi S, Lin O, Chu F, Patil S, Erdjument-Bromage H, Zanzonico P, Hudis C, Studer L, Roboz GJ, Cesarman E, Cerchietti L, Levine R, Melnick A, Larson SM, Lewis JS, Guzman ML, Chiosis G. The epichaperome is an integrated chaperome network that facilitates tumour survival. Nature 2016; 538:397-401. [PMID: 27706135 DOI: 10.1038/nature19807] [Citation(s) in RCA: 189] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 09/02/2016] [Indexed: 01/01/2023]
Abstract
Transient, multi-protein complexes are important facilitators of cellular functions. This includes the chaperome, an abundant protein family comprising chaperones, co-chaperones, adaptors, and folding enzymes-dynamic complexes of which regulate cellular homeostasis together with the protein degradation machinery. Numerous studies have addressed the role of chaperome members in isolation, yet little is known about their relationships regarding how they interact and function together in malignancy. As function is probably highly dependent on endogenous conditions found in native tumours, chaperomes have resisted investigation, mainly due to the limitations of methods needed to disrupt or engineer the cellular environment to facilitate analysis. Such limitations have led to a bottleneck in our understanding of chaperome-related disease biology and in the development of chaperome-targeted cancer treatment. Here we examined the chaperome complexes in a large set of tumour specimens. The methods used maintained the endogenous native state of tumours and we exploited this to investigate the molecular characteristics and composition of the chaperome in cancer, the molecular factors that drive chaperome networks to crosstalk in tumours, the distinguishing factors of the chaperome in tumours sensitive to pharmacologic inhibition, and the characteristics of tumours that may benefit from chaperome therapy. We find that under conditions of stress, such as malignant transformation fuelled by MYC, the chaperome becomes biochemically 'rewired' to form a network of stable, survival-facilitating, high-molecular-weight complexes. The chaperones heat shock protein 90 (HSP90) and heat shock cognate protein 70 (HSC70) are nucleating sites for these physically and functionally integrated complexes. The results indicate that these tightly integrated chaperome units, here termed the epichaperome, can function as a network to enhance cellular survival, irrespective of tissue of origin or genetic background. The epichaperome, present in over half of all cancers tested, has implications for diagnostics and also provides potential vulnerability as a target for drug intervention.
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Affiliation(s)
- Anna Rodina
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Tai Wang
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Pengrong Yan
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Erica DaGama Gomes
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Mark P S Dunphy
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | | | - John Koren
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - John F Gerecitano
- Lymphoma Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Tony Taldone
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Hongliang Zong
- Haematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, USA
| | - Eloisi Caldas-Lopes
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Mary Alpaugh
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Adriana Corben
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Matthew Riolo
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Brad Beattie
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Christina Pressl
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Radu I Peter
- Department of Mathematics, Technical University of Cluj-Napoca, Cluj-Napoca 400114, Romania
| | - Chao Xu
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Robert Trondl
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Hardik J Patel
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Fumiko Shimizu
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Alexander Bolaender
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Chenghua Yang
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Palak Panchal
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Mohammad F Farooq
- Molecular, Cellular &Biomedical Sciences, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Sarah Kishinevsky
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA
| | - Shanu Modi
- Breast Cancer Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Oscar Lin
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Feixia Chu
- Molecular, Cellular &Biomedical Sciences, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Sujata Patil
- Department of Epidemiology-Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Hediye Erdjument-Bromage
- Microchemistry and Proteomics Core, Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Pat Zanzonico
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Clifford Hudis
- Breast Cancer Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Lorenz Studer
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Gail J Roboz
- Haematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, USA
| | - Ethel Cesarman
- Haematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, USA
| | - Leandro Cerchietti
- Haematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, USA
| | - Ross Levine
- Human Oncology and Pathogenesis Program, Sloan Kettering Institute, New York, New York 10065, USA
| | - Ari Melnick
- Haematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, USA
| | - Steven M Larson
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Jason S Lewis
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Monica L Guzman
- Haematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, New York, New York 10065, USA
| | - Gabriela Chiosis
- Program in Chemical Biology, Sloan Kettering Institute, New York, New York 10065, USA.,Breast Cancer Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
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941
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Turner EM, Schlieker C. Pelger-Huët anomaly and Greenberg skeletal dysplasia: LBR-associated diseases of cholesterol metabolism. Rare Dis 2016; 4:e1241363. [PMID: 27830109 PMCID: PMC5077067 DOI: 10.1080/21675511.2016.1241363] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 09/02/2016] [Accepted: 09/21/2016] [Indexed: 12/23/2022] Open
Abstract
Lamin B Receptor (LBR) is an inner nuclear membrane protein associated with the rare human diseases Pelger-Huët anomaly and Greenberg skeletal dysplasia. A new study has used CRISPR/Cas9-mediated genetic manipulations in a human cell system to determine that the molecular etiology of these previously poorly understood disorders is a defect in cholesterol synthesis due to loss of LBR-associated sterol C14 reductase activity. The study furthermore determined that disease-associated LBR point mutations reduce sterol C14 reductase activity by decreasing the affinity of LBR for the reducing agent NADPH. Moreover, two disease-associated LBR truncation mutants were found to be highly unstable at the protein level and are rapidly turned over by a novel nuclear membrane-based protein quality control pathway. Thus, truncated LBR variants can now be used as model substrates for further investigations of nuclear protein quality control to uncover possible implications for other disease-associated nuclear envelopathies.
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Affiliation(s)
- Elizabeth M Turner
- Department of Molecular Biophysics & Biochemistry, Yale University , New Haven, CT, USA
| | - Christian Schlieker
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT, USA; Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
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942
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Sorge M, Brancaccio M. Melusin Promotes a Protective Signal Transduction Cascade in Stressed Hearts. Front Mol Biosci 2016; 3:53. [PMID: 27672636 PMCID: PMC5018970 DOI: 10.3389/fmolb.2016.00053] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 08/29/2016] [Indexed: 01/02/2023] Open
Abstract
Melusin is a chaperone protein selectively expressed in heart and skeletal muscles. Melusin expression levels correlate with cardiac function in pre-clinical models and in human patients with aortic stenosis. Indeed, previous studies in several animal models indicated that Melusin plays a broad cardioprotective role in different pathological conditions. Chaperone proteins, besides playing a role in protein folding, are also able to facilitate supramolecular complex formation and conformational changes due to activation/deactivation of signaling molecules. This role sets chaperone proteins as crucial regulators of intracellular signal transduction pathways. In particular Melusin activates AKT and ERK1/2 signaling, protects cardiomyocytes from apoptosis and induces a compensatory hypertrophic response in several pathological conditions. Therefore, selective delivery of the Melusin gene in heart via cardiotropic adenoviral associated virus serotype 9 (AAV9), may represent a new promising gene-therapy approach for different cardiac pathologies.
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Affiliation(s)
- Matteo Sorge
- Department of Molecular Biotechnology and Health Sciences, University of Torino Torino, Italy
| | - Mara Brancaccio
- Department of Molecular Biotechnology and Health Sciences, University of Torino Torino, Italy
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