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GrpEL1 Regulates Mitochondrial Unfolded Protein Response after Experimental Subarachnoid Hemorrhage in vivo and in vitro. Brain Res Bull 2022; 181:97-108. [DOI: 10.1016/j.brainresbull.2022.01.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/24/2021] [Accepted: 01/22/2022] [Indexed: 12/15/2022]
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2
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Dores-Silva PR, Kiraly VTR, Moritz MNDO, Serrão VHB, Dos Passos PMS, Spagnol V, Teixeira FR, Gava LM, Cauvi DM, Ramos CHI, De Maio A, Borges JC. New insights on human Hsp70-escort protein 1: Chaperone activity, interaction with liposomes, cellular localizations and HSPA's self-assemblies remodeling. Int J Biol Macromol 2021; 182:772-784. [PMID: 33857516 DOI: 10.1016/j.ijbiomac.2021.04.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 04/09/2021] [Accepted: 04/09/2021] [Indexed: 11/24/2022]
Abstract
The 70 kDa heat shock proteins (Hsp70) are prone to self-assembly under thermal stress conditions, forming supramolecular assemblies (SMA), what may have detrimental consequences for cellular viability. In mitochondria, the cochaperone Hsp70-escort protein 1 (Hep1) maintains mitochondrial Hsp70 (mtHsp70) in a soluble and functional state, contributing to preserving proteostasis. Here we investigated the interaction between human Hep1 (hHep1) and HSPA9 (human mtHsp70) or HSPA1A (Hsp70-1A) in monomeric and thermic SMA states to unveil further information about the involved mechanisms. hHep1 was capable of blocking the formation of HSPA SMAs under a thermic treatment and stimulated HSPA ATPase activity in both monomeric and preformed SMA. The interaction of hHep1 with both monomeric and SMA HSPAs displayed a stoichiometric ratio close to 1, suggesting that hHep1 has access to most protomers within the SMA. Interestingly, hHep1 remodeled HSPA9 and HSPA1A SMAs into smaller forms. Furthermore, hHep1 was detected in the mitochondria and nucleus of cells transfected with the respective coding DNA and interacted with liposomes resembling mitochondrial membranes. Altogether, these new features reinforce that hHep1 act as a "chaperone for a chaperone", which may play a critical role in cellular proteostasis.
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Affiliation(s)
- Paulo Roberto Dores-Silva
- Sao Carlos Institute of Chemistry, University of Sao Paulo, Sao Carlos, SP, Brazil; Department of Surgery, School of Medicine, University of California, San Diego, La Jolla, USA
| | | | | | | | | | - Valentine Spagnol
- Department of Genetics and Evolution, Federal University of Sao Carlos, SP, Brazil
| | | | | | - David Mario Cauvi
- Department of Surgery, School of Medicine, University of California, San Diego, La Jolla, USA
| | | | - Antonio De Maio
- Department of Surgery, School of Medicine, University of California, San Diego, La Jolla, USA; Center for Investigations of Health and Education Disparities, University of California, San Diego, La Jolla, USA; Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, USA
| | - Júlio César Borges
- Sao Carlos Institute of Chemistry, University of Sao Paulo, Sao Carlos, SP, Brazil.
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3
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How to get to the other side of the mitochondrial inner membrane – the protein import motor. Biol Chem 2020; 401:723-736. [DOI: 10.1515/hsz-2020-0106] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 02/25/2020] [Indexed: 12/13/2022]
Abstract
AbstractBiogenesis of mitochondria relies on import of more than 1000 different proteins from the cytosol. Approximately 70% of these proteins follow the presequence pathway – they are synthesized with cleavable N-terminal extensions called presequences and reach the final place of their function within the organelle with the help of the TOM and TIM23 complexes in the outer and inner membranes, respectively. The translocation of proteins along the presequence pathway is powered by the import motor of the TIM23 complex. The import motor of the TIM23 complex is localized at the matrix face of the inner membrane and is likely the most complicated Hsp70-based system identified to date. How it converts the energy of ATP hydrolysis into unidirectional translocation of proteins into mitochondria remains one of the biggest mysteries of this translocation pathway. Here, the knowns and the unknowns of the mitochondrial protein import motor are discussed.
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4
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Lu C, Zhang Y, Qin Y, Xu Q, Zhou R, Cui Y, Zhu Y, Zhang X, Zhang J, Wei X, Wang M, Hang B, Mao JH, Snijders AM, Liu M, Hu Z, Shen H, Zhou Z, Guo X, Wu X, Wang X, Xia Y. Human X chromosome exome sequencing identifies BCORL1 as contributor to spermatogenesis. J Med Genet 2020; 58:56-65. [PMID: 32376790 DOI: 10.1136/jmedgenet-2019-106598] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 03/16/2020] [Accepted: 03/21/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND Infertility affects approximately 15% of couples worldwide with male infertility being responsible for approximately 50% of cases. Although accumulating evidence demonstrates the critical role of the X chromosome in spermatogenesis during the last few decades, the expression patterns and potential impact of the X chromosome, together with X linked genes, on male infertility are less well understood. METHODS We performed X chromosome exome sequencing followed by a two-stage independent population validation in 1333 non-obstructive azoospermia cases and 1141 healthy controls to identify variant classes with high likelihood of pathogenicity. To explore the functions of these candidate genes in spermatogenesis, we first knocked down these candidate genes individually in mouse spermatogonial stem cells (SSCs) using short interfering RNA oligonucleotides and then generated candidate genes knockout mice by CRISPR-Cas9 system. RESULTS Four low-frequency variants were identified in four genes (BCORL1, MAP7D3, ARMCX4 and H2BFWT) associated with male infertility. Functional studies of the mouse SSCs revealed that knocking down Bcorl1 or Mtap7d3 could inhibit SSCs self-renewal and knocking down Armcx4 could repress SSCs differentiation in vitro. Using CRISPR-Cas9 system, Bcorl1 and Mtap7d3 knockout mice were generated. Excitingly, Bcorl1 knockout mice were infertile with impaired spermatogenesis. Moreover, Bcorl1 knockout mice exhibited impaired sperm motility and sperm cells displayed abnormal mitochondrial structure. CONCLUSION Our data indicate that the X-linked genes are associated with male infertility and involved in regulating SSCs, which provides a new insight into the role of X-linked genes in spermatogenesis.
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Affiliation(s)
- Chuncheng Lu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Yan Zhang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Yufeng Qin
- Epigenetics & Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, Durham, North Carolina, USA
| | - Qiaoqiao Xu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Ran Zhou
- Nanjing Maternity and Child Health Care Hospital, Nanjing, Jiangsu, China
| | - Yiqiang Cui
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yunfei Zhu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xin Zhang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jintao Zhang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiang Wei
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Min Wang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Bo Hang
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Jian-Hua Mao
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Antoine M Snijders
- Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Mingxi Liu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Zhibin Hu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
- Department of Epidemiology and Biostatistics and Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Hongbing Shen
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
- Department of Epidemiology and Biostatistics and Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Zuomin Zhou
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xuejiang Guo
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xin Wu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xinru Wang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Yankai Xia
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
- Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing, China
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5
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Srivastava S, Vishwanathan V, Birje A, Sinha D, D'Silva P. Evolving paradigms on the interplay of mitochondrial Hsp70 chaperone system in cell survival and senescence. Crit Rev Biochem Mol Biol 2020; 54:517-536. [PMID: 31997665 DOI: 10.1080/10409238.2020.1718062] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The role of mitochondria within a cell has grown beyond being the prime source of cellular energy to one of the major signaling platforms. Recent evidence provides several insights into the crucial roles of mitochondrial chaperones in regulating the organellar response to external triggers. The mitochondrial Hsp70 (mtHsp70/Mortalin/Grp75) chaperone system plays a critical role in the maintenance of proteostasis balance in the organelle. Defects in mtHsp70 network result in attenuated protein transport and misfolding of polypeptides leading to mitochondrial dysfunction. The functions of Hsp70 are primarily governed by J-protein cochaperones. Although human mitochondria possess a single Hsp70, its multifunctionality is characterized by the presence of multiple specific J-proteins. Several studies have shown a potential association of Hsp70 and J-proteins with diverse pathological states that are not limited to their canonical role as chaperones. The role of mitochondrial Hsp70 and its co-chaperones in disease pathogenesis has not been critically reviewed in recent years. We evaluated some of the cellular interfaces where Hsp70 machinery associated with pathophysiological conditions, particularly in context of tumorigenesis and neurodegeneration. The mitochondrial Hsp70 machinery shows a variable localization and integrates multiple components of the cellular processes with varied phenotypic consequences. Although Hsp70 and J-proteins function synergistically in proteins folding, their precise involvement in pathological conditions is mainly idiosyncratic. This machinery is associated with a heterogeneous set of molecules during the progression of a disorder. However, the precise binding to the substrate for a specific physiological response under a disease subtype is still an undocumented area of analysis.
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Affiliation(s)
- Shubhi Srivastava
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | | | - Abhijit Birje
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Devanjan Sinha
- Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Patrick D'Silva
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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6
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The Link That Binds: The Linker of Hsp70 as a Helm of the Protein's Function. Biomolecules 2019; 9:biom9100543. [PMID: 31569820 PMCID: PMC6843406 DOI: 10.3390/biom9100543] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 09/13/2019] [Accepted: 09/21/2019] [Indexed: 12/26/2022] Open
Abstract
The heat shock 70 (Hsp70) family of molecular chaperones plays a central role in maintaining cellular proteostasis. Structurally, Hsp70s are composed of an N-terminal nucleotide binding domain (NBD) which exhibits ATPase activity, and a C-terminal substrate binding domain (SBD). The binding of ATP at the NBD and its subsequent hydrolysis influences the substrate binding affinity of the SBD through allostery. Similarly, peptide binding at the C-terminal SBD stimulates ATP hydrolysis by the N-terminal NBD. Interdomain communication between the NBD and SBD is facilitated by a conserved linker segment. Hsp70s form two main subgroups. Canonical Hsp70 members generally suppress protein aggregation and are also capable of refolding misfolded proteins. Hsp110 members are characterized by an extended lid segment and their function tends to be largely restricted to suppression of protein aggregation. In addition, the latter serve as nucleotide exchange factors (NEFs) of canonical Hsp70s. The linker of the Hsp110 family is less conserved compared to that of the canonical Hsp70 group. In addition, the linker plays a crucial role in defining the functional features of these two groups of Hsp70. Generally, the linker of Hsp70 is quite small and varies in size from seven to thirteen residues. Due to its small size, any sequence variation that Hsp70 exhibits in this motif has a major and unique influence on the function of the protein. Based on sequence data, we observed that canonical Hsp70s possess a linker that is distinct from similar segments present in Hsp110 proteins. In addition, Hsp110 linker motifs from various genera are distinct suggesting that their unique features regulate the flexibility with which the NBD and SBD of these proteins communicate via allostery. The Hsp70 linker modulates various structure-function features of Hsp70 such as its global conformation, affinity for peptide substrate and interaction with co-chaperones. The current review discusses how the unique features of the Hsp70 linker accounts for the functional specialization of this group of molecular chaperones.
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7
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Strangers in strange lands: mitochondrial proteins found at extra-mitochondrial locations. Biochem J 2019; 476:25-37. [DOI: 10.1042/bcj20180473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 11/23/2018] [Accepted: 11/27/2018] [Indexed: 12/18/2022]
Abstract
Abstract
The mitochondrial proteome is estimated to contain ∼1100 proteins, the vast majority of which are nuclear-encoded, with only 13 proteins encoded by the mitochondrial genome. The import of these nuclear-encoded proteins into mitochondria was widely believed to be unidirectional, but recent discoveries have revealed that many these ‘mitochondrial’ proteins are exported, and have extra-mitochondrial activities divergent from their mitochondrial function. Surprisingly, three of the exported proteins discovered thus far are mitochondrially encoded and have significantly different extra-mitochondrial roles than those performed within the mitochondrion. In this review, we will detail the wide variety of proteins once thought to only reside within mitochondria, but now known to ‘emigrate’ from mitochondria in order to attain ‘dual citizenship’, present both within mitochondria and elsewhere.
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8
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Nyakundi DO, Bentley SJ, Boshoff A. Hsp70 Escort Protein: More Than a Regulator of Mitochondrial Hsp70. CURR PROTEOMICS 2018. [DOI: 10.2174/1570164615666180713104919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Hsp70 members occupy a central role in proteostasis and are found in different eukaryotic
cellular compartments. The mitochondrial Hsp70/J-protein machinery performs multiple functions vital
for the proper functioning of the mitochondria, including forming part of the import motor that
transports proteins from the cytosol into the matrix and inner membrane, and subsequently folds these
proteins in the mitochondria. However, unlike other Hsp70s, mitochondrial Hsp70 (mtHsp70) has the
propensity to self-aggregate, accumulating as insoluble aggregates. The self-aggregation of mtHsp70 is
caused by both interdomain and intramolecular communication within the ATPase and linker domains.
Since mtHsp70 is unable to fold itself into an active conformation, it requires an Hsp70 escort protein
(Hep) to both inhibit self-aggregation and promote the correct folding. Hep1 orthologues are present in
the mitochondria of many eukaryotic cells but are absent in prokaryotes. Hep1 proteins are relatively
small and contain a highly conserved zinc-finger domain with one tetracysteine motif that is essential
for binding zinc ions and maintaining the function and solubility of the protein. The zinc-finger domain
lies towards the C-terminus of Hep1 proteins, with very little conservation outside of this domain.
Other than maintaining mtHsp70 in a functional state, Hep1 proteins play a variety of other roles in the
cell and have been proposed to function as both chaperones and co-chaperones. The cellular
localisation and some of the functions are often speculative and are not common to all Hep1 proteins
analysed to date.
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Affiliation(s)
- David O. Nyakundi
- Biotechnology Innovation Centre, Rhodes University, Grahamstown 6140, South Africa
| | - Stephen J. Bentley
- Biotechnology Innovation Centre, Rhodes University, Grahamstown 6140, South Africa
| | - Aileen Boshoff
- Biotechnology Innovation Centre, Rhodes University, Grahamstown 6140, South Africa
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9
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A folding nucleus and minimal ATP binding domain of Hsp70 identified by single-molecule force spectroscopy. Proc Natl Acad Sci U S A 2018; 115:4666-4671. [PMID: 29669923 DOI: 10.1073/pnas.1716899115] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The folding pathways of large proteins are complex, with many of them requiring the aid of chaperones and others folding spontaneously. Along the folding pathways, partially folded intermediates are frequently populated; their role in the driving of the folding process is unclear. The structures of these intermediates are generally not amenable to high-resolution structural techniques because of their transient nature. Here we employed single-molecule force measurements to scrutinize the hierarchy of intermediate structures along the folding pathway of the nucleotide binding domain (NBD) of Escherichia coli Hsp70 DnaK. DnaK-NBD is a member of the sugar kinase superfamily that includes Hsp70s and the cytoskeletal protein actin. Using optical tweezers, a stable nucleotide-binding competent en route folding intermediate comprising lobe II residues (183-383) was identified as a critical checkpoint for productive folding. We obtained a structural snapshot of this folding intermediate that shows native-like conformation. To assess the fundamental role of folded lobe II for efficient folding, we turned our attention to yeast mitochondrial NBD, which does not fold without a dedicated chaperone. After replacing the yeast lobe II residues with stable E. coli lobe II, the obtained chimeric protein showed native-like ATPase activity and robust folding into the native state, even in the absence of chaperone. In summary, lobe II is a stable nucleotide-binding competent folding nucleus that is the key to time-efficient folding and possibly resembles a common ancestor domain. Our findings provide a conceptual framework for the folding pathways of other members of this protein superfamily.
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10
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Penna C, Sorge M, Femminò S, Pagliaro P, Brancaccio M. Redox Aspects of Chaperones in Cardiac Function. Front Physiol 2018; 9:216. [PMID: 29615920 PMCID: PMC5864891 DOI: 10.3389/fphys.2018.00216] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 02/26/2018] [Indexed: 12/14/2022] Open
Abstract
Molecular chaperones are stress proteins that allow the correct folding or unfolding as well as the assembly or disassembly of macromolecular cellular components. Changes in expression and post-translational modifications of chaperones have been linked to a number of age- and stress-related diseases including cancer, neurodegeneration, and cardiovascular diseases. Redox sensible post-translational modifications, such as S-nitrosylation, glutathionylation and phosphorylation of chaperone proteins have been reported. Redox-dependent regulation of chaperones is likely to be a phenomenon involved in metabolic processes and may represent an adaptive response to several stress conditions, especially within mitochondria, where it impacts cellular bioenergetics. These post-translational modifications might underlie the mechanisms leading to cardioprotection by conditioning maneuvers as well as to ischemia/reperfusion injury. In this review, we discuss this topic and focus on two important aspects of redox-regulated chaperones, namely redox regulation of mitochondrial chaperone function and cardiac protection against ischemia/reperfusion injury.
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Affiliation(s)
- Claudia Penna
- Department of Clinical and Biological Sciences, University of Torino, Torino, Italy
| | - Matteo Sorge
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Saveria Femminò
- Department of Clinical and Biological Sciences, University of Torino, Torino, Italy
| | - Pasquale Pagliaro
- Department of Clinical and Biological Sciences, University of Torino, Torino, Italy
| | - Mara Brancaccio
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
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11
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Carvalho NR, Tassi CC, Dobraschinski F, Amaral GP, Zemolin AP, Golombieski RM, Dalla Corte CL, Franco JL, Mauriz JL, González-Gallego J, Soares FA. Reversal of bioenergetics dysfunction by diphenyl diselenide is critical to protection against the acetaminophen-induced acute liver failure. Life Sci 2017; 180:42-50. [DOI: 10.1016/j.lfs.2017.05.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 04/29/2017] [Accepted: 05/10/2017] [Indexed: 02/05/2023]
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12
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Magesky A, de Oliveira Ribeiro CA, Beaulieu L, Pelletier É. Silver nanoparticles and dissolved silver activate contrasting immune responses and stress-induced heat shock protein expression in sea urchin. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2017; 36:1872-1886. [PMID: 27943424 DOI: 10.1002/etc.3709] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 09/14/2016] [Accepted: 12/08/2016] [Indexed: 06/06/2023]
Abstract
Using immune cells of sea urchin Strongylocentrotus droebachiensis in early development as a model, the cellular protective mechanisms against ionic and poly(allylamine)-coated silver nanoparticle (AgNPs; 14 ± 6 nm) treatments at 100 μg L-1 were investigated. Oxidative stress, heat shock protein expression, and pigment production by spherulocytes were determined as well as AgNP translocation pathways and their multiple effects on circulating coelomocytes. Sea urchins showed an increasing resilience to Ag over time because ionic Ag is accumulated in a steady way, although nanoAg levels dropped between 48 h and 96 h. A clotting reaction emerged on tissues injured by dissolved Ag (present as chloro-complexes in seawater) between 12 h and 48 h. Silver contamination and nutritional state influenced the production of reactive oxygen species. After passing through coelomic sinuses and gut, AgNPs were found in coelomocytes. Inside blood vessels, apoptosis-like processes appeared in coelomocytes highly contaminated by poly(allylamine)-coated AgNPs. Increasing levels of Ag accumulated by urchins once exposed to AgNPs pointed to a Trojan-horse mechanism operating over 12-d exposure. However, under short-term treatments, physical interactions of poly(allylamine)-coated AgNPs with cell structures might be, at some point, predominant and responsible for the highest levels of stress-related proteins detected. The present study is the first report detailing nano-translocation in a marine organism and multiple mechanisms by which sea urchin cells can deal with toxic AgNPs. Environ Toxicol Chem 2017;36:1872-1886. © 2016 SETAC.
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Affiliation(s)
- Adriano Magesky
- Institut de sciences de la mer de Rimouski, Université du Québec à Rimouski, Rimouski, Québec, Canada
| | | | - Lucie Beaulieu
- Département des sciences des aliments, Université Laval, Québec, Québec, Canada
| | - Émilien Pelletier
- Institut de sciences de la mer de Rimouski, Université du Québec à Rimouski, Rimouski, Québec, Canada
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13
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Minde D, Dunker AK, Lilley KS. Time, space, and disorder in the expanding proteome universe. Proteomics 2017; 17:1600399. [PMID: 28145059 PMCID: PMC5573936 DOI: 10.1002/pmic.201600399] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 01/16/2017] [Accepted: 01/25/2017] [Indexed: 12/31/2022]
Abstract
Proteins are highly dynamic entities. Their myriad functions require specific structures, but proteins' dynamic nature ranges all the way from the local mobility of their amino acid constituents to mobility within and well beyond single cells. A truly comprehensive view of the dynamic structural proteome includes: (i) alternative sequences, (ii) alternative conformations, (iii) alternative interactions with a range of biomolecules, (iv) cellular localizations, (v) alternative behaviors in different cell types. While these aspects have traditionally been explored one protein at a time, we highlight recently emerging global approaches that accelerate comprehensive insights into these facets of the dynamic nature of protein structure. Computational tools that integrate and expand on multiple orthogonal data types promise to enable the transition from a disjointed list of static snapshots to a structurally explicit understanding of the dynamics of cellular mechanisms.
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Affiliation(s)
- David‐Paul Minde
- Cambridge Systems Biology CentreUniversity of CambridgeCambridgeUK
- Cambridge Centre for ProteomicsDepartment of BiochemistryUniversity of CambridgeCambridgeUK
- Department of BiochemistryUniversity of CambridgeCambridgeUK
| | - A. Keith Dunker
- Center for Computational Biology and BioinformaticsIndiana University School of MedicineIndianapolisINUSA
| | - Kathryn S. Lilley
- Cambridge Systems Biology CentreUniversity of CambridgeCambridgeUK
- Cambridge Centre for ProteomicsDepartment of BiochemistryUniversity of CambridgeCambridgeUK
- Department of BiochemistryUniversity of CambridgeCambridgeUK
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14
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Cascella K, Jollivet D, Papot C, Léger N, Corre E, Ravaux J, Clark MS, Toullec JY. Diversification, evolution and sub-functionalization of 70kDa heat-shock proteins in two sister species of antarctic krill: differences in thermal habitats, responses and implications under climate change. PLoS One 2015; 10:e0121642. [PMID: 25835552 PMCID: PMC4383606 DOI: 10.1371/journal.pone.0121642] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 02/03/2015] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND A comparative thermal tolerance study was undertaken on two sister species of Euphausiids (Antarctic krills) Euphausia superba and Euphausia crystallorophias. Both are essential components of the Southern Ocean ecosystem, but occupy distinct environmental geographical locations with slightly different temperature regimes. They therefore provide a useful model system for the investigation of adaptations to thermal tolerance. METHODOLOGY/PRINCIPAL FINDING Initial CTmax studies showed that E. superba was slightly more thermotolerant than E. crystallorophias. Five Hsp70 mRNAs were characterized from the RNAseq data of both species and subsequent expression kinetics studies revealed notable differences in induction of each of the 5 orthologues between the two species, with E. crystallorophias reacting more rapidly than E. superba. Furthermore, analyses conducted to estimate the evolutionary rates and selection strengths acting on each gene tended to support the hypothesis that diversifying selection has contributed to the diversification of this gene family, and led to the selective relaxation on the inducible C form with its possible loss of function in the two krill species. CONCLUSIONS The sensitivity of the epipelagic species E. crystallorophias to temperature variations and/or its adaptation to cold is enhanced when compared with its sister species, E. superba. These results indicate that ice krill could be the first of the two species to be impacted by the warming of coastal waters of the Austral ocean in the coming years due to climate change.
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Affiliation(s)
- Kévin Cascella
- Sorbonne Universités, UPMC Université Paris 06, UMR 7144 CNRS, Equipe ABICE, Station Biologique de Roscoff, 29680 Roscoff, France
- CNRS, UMR 7144, Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, 29680 Roscoff, France
| | - Didier Jollivet
- Sorbonne Universités, UPMC Université Paris 06, UMR 7144 CNRS, Equipe ABICE, Station Biologique de Roscoff, 29680 Roscoff, France
- CNRS, UMR 7144, Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, 29680 Roscoff, France
| | - Claire Papot
- Université de Lille1, CNRS UMR8198, Ecoimmunology of Marine Annelids, 59655 Villeneuve d’Ascq, France
| | - Nelly Léger
- Sorbonne Universités, UPMC Université Paris 06, UMR 7208 CNRS, Equipe AMEX, 75005 Paris, France
- CNRS 7208, BOREA, UPMC Université Paris 06, 75005 Paris, France
| | - Erwan Corre
- Sorbonne Universités, UPMC Université Paris 06, FR 2424 CNRS, ABiMS, Analysis and Bioinformatics for Marine Science, Station Biologique de Roscoff, 29680 Roscoff, France
- CNRS, FR 2424, Station Biologique de Roscoff, 29680 Roscoff, France
| | - Juliette Ravaux
- Sorbonne Universités, UPMC Université Paris 06, UMR 7208 CNRS, Equipe AMEX, 75005 Paris, France
- CNRS 7208, BOREA, UPMC Université Paris 06, 75005 Paris, France
| | - Melody S. Clark
- British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, United Kingdom
| | - Jean-Yves Toullec
- Sorbonne Universités, UPMC Université Paris 06, UMR 7144 CNRS, Equipe ABICE, Station Biologique de Roscoff, 29680 Roscoff, France
- CNRS, UMR 7144, Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, 29680 Roscoff, France
- * E-mail:
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15
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Böttinger L, Oeljeklaus S, Guiard B, Rospert S, Warscheid B, Becker T. Mitochondrial heat shock protein (Hsp) 70 and Hsp10 cooperate in the formation of Hsp60 complexes. J Biol Chem 2015; 290:11611-22. [PMID: 25792736 DOI: 10.1074/jbc.m115.642017] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Indexed: 11/06/2022] Open
Abstract
Mitochondrial Hsp70 (mtHsp70) mediates essential functions for mitochondrial biogenesis, like import and folding of proteins. In these processes, the chaperone cooperates with cochaperones, the presequence translocase, and other chaperone systems. The chaperonin Hsp60, together with its cofactor Hsp10, catalyzes folding of a subset of mtHsp70 client proteins. Hsp60 forms heptameric ring structures that provide a cavity for protein folding. How the Hsp60 rings are assembled is poorly understood. In a comprehensive interaction study, we found that mtHsp70 associates with Hsp60 and Hsp10. Surprisingly, mtHsp70 interacts with Hsp10 independently of Hsp60. The mtHsp70-Hsp10 complex binds to the unassembled Hsp60 precursor to promote its assembly into mature Hsp60 complexes. We conclude that coupling to Hsp10 recruits mtHsp70 to mediate the biogenesis of the heptameric Hsp60 rings.
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Affiliation(s)
- Lena Böttinger
- From the Institut für Biochemie und Molekularbiologie, ZBMZ, the Fakultät für Biologie
| | - Silke Oeljeklaus
- Institut für Biologie II, Abteilung Biochemie und Funktionelle Proteomik, Universität Freiburg, 79104 Freiburg, Germany, the BIOSS Centre for Biological Signalling Studies, and
| | - Bernard Guiard
- the Centre de Génétique Moléculaire, CNRS, 91190 Gif-sur-Yvette, France
| | - Sabine Rospert
- From the Institut für Biochemie und Molekularbiologie, ZBMZ, the BIOSS Centre for Biological Signalling Studies, and
| | - Bettina Warscheid
- Institut für Biologie II, Abteilung Biochemie und Funktionelle Proteomik, Universität Freiburg, 79104 Freiburg, Germany, the BIOSS Centre for Biological Signalling Studies, and
| | - Thomas Becker
- From the Institut für Biochemie und Molekularbiologie, ZBMZ, the Fakultät für Biologie, the BIOSS Centre for Biological Signalling Studies, and
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16
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Trösch R, Mühlhaus T, Schroda M, Willmund F. ATP-dependent molecular chaperones in plastids--More complex than expected. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:872-88. [PMID: 25596449 DOI: 10.1016/j.bbabio.2015.01.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/03/2015] [Accepted: 01/08/2015] [Indexed: 11/27/2022]
Abstract
Plastids are a class of essential plant cell organelles comprising photosynthetic chloroplasts of green tissues, starch-storing amyloplasts of roots and tubers or the colorful pigment-storing chromoplasts of petals and fruits. They express a few genes encoded on their organellar genome, called plastome, but import most of their proteins from the cytosol. The import into plastids, the folding of freshly-translated or imported proteins, the degradation or renaturation of denatured and entangled proteins, and the quality-control of newly folded proteins all require the action of molecular chaperones. Members of all four major families of ATP-dependent molecular chaperones (chaperonin/Cpn60, Hsp70, Hsp90 and Hsp100 families) have been identified in plastids from unicellular algae to higher plants. This review aims not only at giving an overview of the most current insights into the general and conserved functions of these plastid chaperones, but also into their specific plastid functions. Given that chloroplasts harbor an extreme environment that cycles between reduced and oxidized states, that has to deal with reactive oxygen species and is highly reactive to environmental and developmental signals, it can be presumed that plastid chaperones have evolved a plethora of specific functions some of which are just about to be discovered. Here, the most urgent questions that remain unsolved are discussed, and guidance for future research on plastid chaperones is given. This article is part of a Special Issue entitled: Chloroplast Biogenesis.
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Affiliation(s)
- Raphael Trösch
- TU Kaiserslautern, Molecular Biotechnology & Systems Biology, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany; HU Berlin, Institute of Biology, Chausseestraße 117, 10115 Berlin, Germany; TU Kaiserslautern, Molecular Genetics of Eukaryotes, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany.
| | - Timo Mühlhaus
- TU Kaiserslautern, Molecular Biotechnology & Systems Biology, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany.
| | - Michael Schroda
- TU Kaiserslautern, Molecular Biotechnology & Systems Biology, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany.
| | - Felix Willmund
- TU Kaiserslautern, Molecular Genetics of Eukaryotes, Paul-Ehrlich-Straße 23, 67663 Kaiserslautern, Germany.
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17
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Regev-Rudzki N, Gabriel K, Bursać D. The evolution and function of co-chaperones in mitochondria. Subcell Biochem 2015; 78:201-217. [PMID: 25487023 DOI: 10.1007/978-3-319-11731-7_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Mitochondrial chaperones mediate and affect critical organellar processes, essential for cellular function. These chaperone systems have both prokaryotic and eukaryotic features. While some of the mitochondrial co-chaperones have clear homologues in prokaryotes, some are unique to eukaryotes and have no homologues in the chaperone machinery of other cellular compartments. The mitochondrial co-chaperones are required for protein import into the organelle and in enforcing the structure of the main chaperones. In addition to novel types of interaction with their senior partners, unexpected and essential interactions between the co-chaperones themselves have recently been described.
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Affiliation(s)
- Neta Regev-Rudzki
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovolt, Israel,
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18
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Talla V, Porciatti V, Chiodo V, Boye SL, Hauswirth WW, Guy J. Gene therapy with mitochondrial heat shock protein 70 suppresses visual loss and optic atrophy in experimental autoimmune encephalomyelitis. Invest Ophthalmol Vis Sci 2014; 55:5214-26. [PMID: 25015358 DOI: 10.1167/iovs.14-14688] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
PURPOSE To rescue visual loss and optic neuropathy in experimental autoimmune encephalomyelitis (EAE). METHODS Encephalomyelitis was induced in mice that received intravitreal injections of AAV2-mtHSP70Flag or AAV2-Cox8-mCherry. Additional mice were injected with AAV2-Cox8-mCherry, but not sensitized for EAE. Visual function was assessed by pattern electroretinograms (PERG) at 1, 3, and 6 months post injection (MPI). Optical coherence tomography (OCT) evaluated the thickness of the inner plexiform layer + nerve fiber layers at 1, 3, and 6 MPI. Retinas and optic nerves (ONs) of mice euthanized 6 MPI were processed for light and electron microscopy. Expression of mtHSP70Flag in the retina and ONs was evaluated by RT-PCR, immunofluorescence, and Western blotting. The activities of respiratory complexes I and III, as well as mitochondrial protein import were quantitated. RESULTS Expression: immunofluorescence revealed punctate and perinuclear expression of mtHSP70Flag that colocalized with mitochondrial porin in thy1.2 labeled retinal ganglion cells (RGCs). Immunoblotting and RT-PCR confirmed mtHSP70Flag expression in the retina and ON. Rescue: treatment with mtHSP70Flag resulted in a 44% increase in PERG amplitude and less delays in latency relative to the EAE-mCherry group that also showed progressive inner retinal thinning. At 6 MPI, the almost 50% loss of RGCs and optic nerve axons in EAE mice was suppressed by mtHSP70Flag. In addition, retinas of EAE-mtHSP70Flag mice showed nearly complete rescue of complex I and III activities that was reduced by one-third in the EAE-mCherry retinas. Lastly, reductions in import of COX8-mCherry into mitochondria of mice sensitized for EAE improved by 30% with mtHSP70Flag gene therapy. CONCLUSIONS Mitochondrial HSP70 ameliorates mitochondrial dysfunction that culminates in irreversible visual loss and atrophy of the optic nerve in EAE suggesting that it may be useful to prevent irreversible disability in patients with optic neuritis and multiple sclerosis (MS).
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Affiliation(s)
- Venu Talla
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami, Miller School of Medicine, Miami, Florida, United States
| | - Vittorio Porciatti
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami, Miller School of Medicine, Miami, Florida, United States
| | - Vince Chiodo
- Department of Ophthalmology, University of Florida, Gainesville, Florida, United States
| | - Sanford L Boye
- Department of Ophthalmology, University of Florida, Gainesville, Florida, United States
| | - William W Hauswirth
- Department of Ophthalmology, University of Florida, Gainesville, Florida, United States
| | - John Guy
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami, Miller School of Medicine, Miami, Florida, United States
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19
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In vitro characterization of bacterial and chloroplast Hsp70 systems reveals an evolutionary optimization of the co-chaperones for their Hsp70 partner. Biochem J 2014; 460:13-24. [PMID: 24564700 DOI: 10.1042/bj20140001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The chloroplast Hsp70 (heat-shock protein of 70 kDa) system involved in protein folding in Chlamydomonas reinhardtii consists of HSP70B, the DnaJ homologue CDJ1 and the GrpE-type nucleotide-exchange factor CGE1. The finding that HSP70B needs to be co-expressed with HEP2 (Hsp70 escort protein 2) to become functional allowed the reconstitution of the chloroplast Hsp70 system in vitro and comparison with the homologous Escherichia coli system. Both systems support luciferase refolding and display ATPase and holdase activities. Steady-state activities are low and strongly stimulated by the co-chaperones, whose concentrations need to be balanced to optimally support luciferase refolding. Although the co-chaperones of either system generally stimulate ATPase and folding-assistance activities of the other, luciferase refolding is reduced ~10-fold and <2-fold if either Hsp70 is supplemented with the foreign DnaJ and GrpE protein respectively, suggesting an evolutionary specialization of the co-chaperones for their Hsp70 partner. Distinct features are that HSP70B's steady-state ATPase exhibits ~20-fold higher values for Vmax and Km and that the HSP70B system displays a ~6-fold higher folding assistance on denatured luciferase. Although truncating up to 16 N-terminal amino acids of CGE1 does not affect HSP70B's general ATPase and folding-assistance activities in the physiological temperature range, further deletions hampering dimerization of CGE1 via its N-terminal coiled coil do.
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20
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Lewrenz I, Rietzschel N, Guiard B, Lill R, van der Laan M, Voos W. The functional interaction of mitochondrial Hsp70s with the escort protein Zim17 is critical for Fe/S biogenesis and substrate interaction at the inner membrane preprotein translocase. J Biol Chem 2013; 288:30931-43. [PMID: 24030826 DOI: 10.1074/jbc.m113.465997] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The yeast protein Zim17 belongs to a unique class of co-chaperones that maintain the solubility of Hsp70 proteins in mitochondria and plastids of eukaryotic cells. However, little is known about the functional cooperation between Zim17 and mitochondrial Hsp70 proteins in vivo. To analyze the effects of a loss of Zim17 function in the authentic environment, we introduced novel conditional mutations within the ZIM17 gene of the model organism Saccharomyces cerevisiae that allowed a recovery of temperature-sensitive but respiratory competent zim17 mutant cells. On fermentable growth medium, the mutant cells were prone to acquire respiratory deficits and showed a strong aggregation of the mitochondrial Hsp70 Ssq1 together with a concomitant defect in Fe/S protein biogenesis. In contrast, under respiring conditions, the mitochondrial Hsp70s Ssc1 and Ssq1 exhibited only a partial aggregation. We show that the induction of the zim17 mutant phenotype leads to strong import defects for Ssc1-dependent matrix-targeted precursor proteins that correlate with a significantly reduced binding of newly imported substrate proteins to Ssc1. We conclude that Zim17 is not only required for the maintenance of mtHsp70 solubility but also directly assists the functional interaction of mtHsp70 with substrate proteins in a J-type co-chaperone-dependent manner.
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Affiliation(s)
- Ilka Lewrenz
- From the Institut für Biochemie und Molekularbiologie, Universität Bonn, Nussallee 11, D-53115 Bonn, Germany
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21
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Real-time observation of the conformational dynamics of mitochondrial Hsp70 by spFRET. EMBO J 2013; 32:1639-49. [PMID: 23624933 DOI: 10.1038/emboj.2013.89] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 03/21/2013] [Indexed: 11/08/2022] Open
Abstract
The numerous functions of the important class of molecular chaperones, heat shock proteins 70 (Hsp70), rely on cycles of intricate conformational changes driven by ATP-hydrolysis and regulated by cochaperones and substrates. Here, we used Förster resonance energy transfer to study the conformational dynamics of individual molecules of Ssc1, a mitochondrial Hsp70, in real time. The intrinsic dynamics of the substrate-binding domain of Ssc1 was observed to be uncoupled from the dynamic interactions between substrate- and nucleotide-binding domains. Analysis of the fluctuations in the interdomain separation revealed frequent transitions to a nucleotide-free state. The nucleotide-exchange factor Mge1 did not induce ADP release, as expected, but rather facilitated binding of ATP. These results indicate that the conformational cycle of Ssc1 is more elaborate than previously thought and provide insight into how the Hsp70s can perform a wide variety of functions.
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22
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Lionaki E, Tavernarakis N. Oxidative stress and mitochondrial protein quality control in aging. J Proteomics 2013; 92:181-94. [PMID: 23563202 DOI: 10.1016/j.jprot.2013.03.022] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 02/22/2013] [Accepted: 03/25/2013] [Indexed: 12/17/2022]
Abstract
Mitochondrial protein quality control incorporates an elaborate network of chaperones and proteases that survey the organelle for misfolded or unfolded proteins and toxic aggregates. Repair of misfolded or aggregated protein and proteolytic removal of irreversibly damaged proteins are carried out by the mitochondrial protein quality control system. Initial maturation and folding of the nuclear or mitochondrial-encoded mitochondrial proteins are mediated by processing peptidases and chaperones that interact with the protein translocation machinery. Mitochondrial proteins are subjected to cumulative oxidative damage. Thus, impairment of quality control processes may cause mitochondrial dysfunction. Aging has been associated with a marked decline in the effectiveness of mitochondrial protein quality control. Here, we present an overview of the chaperones and proteases involved in the initial folding and maturation of new, incoming precursor molecules, and the subsequent repair and removal of oxidized aggregated proteins. In addition, we highlight the link between mitochondrial protein quality control mechanisms and the aging process. This article is part of a Special Issue entitled: Posttranslational Protein modifications in biology and Medicine.
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Affiliation(s)
- Eirini Lionaki
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion 71110, Crete, Greece
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