1
|
Silva NSM, Rodrigues LFDC, Dores-Silva PR, Montanari CA, Ramos CHI, Barbosa LRS, Borges JC. Structural, thermodynamic and functional studies of human 71 kDa heat shock cognate protein (HSPA8/hHsc70). BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2021; 1869:140719. [PMID: 34571256 DOI: 10.1016/j.bbapap.2021.140719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 08/29/2021] [Accepted: 09/21/2021] [Indexed: 01/14/2023]
Abstract
Human 71 kDa heat shock cognate protein (HSPA8, also known as Hsc70, Hsp70-8, Hsc71, Hsp71 or Hsp73) is a constitutively expressed chaperone that is critical for cell proteostasis. In the cytosol, HSPA8 plays a pivotal role in folding and refolding, facilitates protein trafficking across membranes and targets proteins for degradation, among other functions. Here, we report an in solution study of recombinant HSPA8 (rHSPA8) using a variety of biophysical and biochemical approaches. rHSPA8 shares several structural and functional similarities with others human Hsp70s. It has two domains with different stabilities and interacts with adenosine nucleotides with dissociation constants in the low micromolar range, which were higher in the presence of Mg2+. rHSPA8 showed lower ATPase activity than its homolog HSPA5/hGrp78/hBiP, but it was 4-fold greater than that of recombinant HSPA1A/hHsp70-1A, with which it is 86% identical. Small angle X-ray scattering indicated that rHSPA8 behaved as an elongated monomeric protein in solution with dimensions similar to those observed for HSPA1A. In addition, rHSPA8 showed structural flexibility between its compacted and extended conformations. The data also indicated that HSPA8 has capacity in preventing the aggregation of model client proteins. The present study expands the understanding of the structure and activity of this chaperone and aligns with the idea that human homologous Hsp70s have divergent functions.
Collapse
Affiliation(s)
| | | | - Paulo Roberto Dores-Silva
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil; Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery School of Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | | | | | - Leandro Ramos Souza Barbosa
- Institute of Physics, University of São Paulo, São Paulo, SP, Brazil; Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
| | - Júlio César Borges
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil.
| |
Collapse
|
2
|
Mitochondrial HSP70 Chaperone System-The Influence of Post-Translational Modifications and Involvement in Human Diseases. Int J Mol Sci 2021; 22:ijms22158077. [PMID: 34360841 PMCID: PMC8347752 DOI: 10.3390/ijms22158077] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/23/2021] [Accepted: 07/26/2021] [Indexed: 01/25/2023] Open
Abstract
Since their discovery, heat shock proteins (HSPs) have been identified in all domains of life, which demonstrates their importance and conserved functional role in maintaining protein homeostasis. Mitochondria possess several members of the major HSP sub-families that perform essential tasks for keeping the organelle in a fully functional and healthy state. In humans, the mitochondrial HSP70 chaperone system comprises a central molecular chaperone, mtHSP70 or mortalin (HSPA9), which is actively involved in stabilizing and importing nuclear gene products and in refolding mitochondrial precursor proteins, and three co-chaperones (HSP70-escort protein 1-HEP1, tumorous imaginal disc protein 1-TID-1, and Gro-P like protein E-GRPE), which regulate and accelerate its protein folding functions. In this review, we summarize the roles of mitochondrial molecular chaperones with particular focus on the human mtHsp70 and its co-chaperones, whose deregulated expression, mutations, and post-translational modifications are often considered to be the main cause of neurological disorders, genetic diseases, and malignant growth.
Collapse
|
3
|
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.
Collapse
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.
| |
Collapse
|
4
|
Structural-functional diversity of malaria parasite's PfHSP70-1 and PfHSP40 chaperone pair gives an edge over human orthologs in chaperone-assisted protein folding. Biochem J 2021; 477:3625-3643. [PMID: 32893851 DOI: 10.1042/bcj20200434] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/02/2020] [Accepted: 09/07/2020] [Indexed: 12/13/2022]
Abstract
Plasmodium falciparum, the human malaria parasite harbors a metastable proteome which is vulnerable to proteotoxic stress conditions encountered during its lifecycle. How parasite's chaperone machinery is able to maintain its aggregation-prone proteome in functional state, is poorly understood. As HSP70-40 system forms the central hub in cellular proteostasis, we investigated the protein folding capacity of PfHSP70-1 and PfHSP40 chaperone pair and compared it with human orthologs (HSPA1A and DNAJA1). Despite the structural similarity, we observed that parasite chaperones and their human orthologs exhibit striking differences in conformational dynamics. Comprehensive biochemical investigations revealed that PfHSP70-1 and PfHSP40 chaperone pair has better protein folding, aggregation inhibition, oligomer remodeling and disaggregase activities than their human orthologs. Chaperone-swapping experiments suggest that PfHSP40 can also efficiently cooperate with human HSP70 to facilitate the folding of client-substrate. SPR-derived kinetic parameters reveal that PfHSP40 has higher binding affinity towards unfolded substrate than DNAJA1. Interestingly, the observed slow dissociation rate of PfHSP40-substrate interaction allows PfHSP40 to maintain the substrate in folding-competent state to minimize its misfolding. Structural investigation through small angle x-ray scattering gave insights into the conformational architecture of PfHSP70-1 (monomer), PfHSP40 (dimer) and their complex. Overall, our data suggest that the parasite has evolved functionally diverged and efficient chaperone machinery which allows the human malaria parasite to survive in hostile conditions. The distinct allosteric landscapes and interaction kinetics of plasmodial chaperones open avenues for the exploration of small-molecule based antimalarial interventions.
Collapse
|
5
|
Dores-Silva PR, Cauvi DM, Kiraly VTR, Borges JC, De Maio A. Human HSPA9 (mtHsp70, mortalin) interacts with lipid bilayers containing cardiolipin, a major component of the inner mitochondrial membrane. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183436. [PMID: 32781155 DOI: 10.1016/j.bbamem.2020.183436] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 07/21/2020] [Accepted: 07/22/2020] [Indexed: 12/16/2022]
Abstract
Mitochondrial Hsp70 (HSPA9, mtHsp70, mortalin) in conjunction with a complex set of other proteins is involved in the transport of polypeptides across the mitochondrial matrix. This observation allows us to hypothesize that HSPA9 might interact with membranes directly, similarly to other Hsp70s. Thus, we investigated whether human HSPA9 could also get inserted into lipid membranes. Human HSPA9 was incubated with liposomes made of lipids found within the mitochondrial membrane, such as 1', 3'-bis [1, 2-dimyristoyl-sn-glycero-3-phospho]-glycerol (CL), palmitoyl-oleoyl phosphocholine (POPC), palmitoyl-oleoyl phosphoserine (POPS), and palmitoyl-oleoyl phosphoethanolamine (POPE). HSPA9 displayed a predilection for CL and POPS, and low affinity for POPC and POPE, suggesting that the proteins have high specificity for negatively charged phospholipids. Then, liposomes were made with a composition resembling either the outer or inner mitochondrial membrane (OMM or IMM, respectively). We observed that HSPA9 has a higher affinity for IMM than OMM, which is consistent with the higher content of CL in the IMM. A comparison for the incorporation into POPS or CL liposomes by HSPA9 or HSPA1 indicated that both proteins behaved very similarly when exposed to CL liposomes, but differently with POPS liposomes, which was further corroborated by their susceptibility to proteinase K digestion after incorporation into liposomes. The measurement of thermodynamic parameters also showed that the interaction of both proteins with CL and POPS liposomes was different. Overall, our data showed that HSPA9 is prone to interact with membranes resembling the IMM that may be important for its role in the translocation of proteins into the mitochondria.
Collapse
Affiliation(s)
- Paulo Roberto Dores-Silva
- Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA; São Carlos Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - David M Cauvi
- Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Vanessa T R Kiraly
- São Carlos Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Júlio C Borges
- São Carlos Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Antonio De Maio
- Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA; Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA.
| |
Collapse
|
6
|
Kiraly VTR, Dores-Silva PR, Serrão VHB, Cauvi DM, De Maio A, Borges JC. Thermal aggregates of human mortalin and Hsp70-1A behave as supramolecular assemblies. Int J Biol Macromol 2020; 146:320-331. [PMID: 31899237 PMCID: PMC7024674 DOI: 10.1016/j.ijbiomac.2019.12.236] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/24/2019] [Accepted: 12/25/2019] [Indexed: 12/12/2022]
Abstract
The Hsp70 family of heat shock proteins plays a critical function in maintaining cellular homeostasis within various subcellular compartments. The human mitochondrial Hsp70 (HSPA9) has been associated with cellular death, senescence, cancer and neurodegenerative diseases, which is the rational for the name mortalin. It is well documented that mortalin, such as other Hsp70s, is prone to self-aggregation, which is related to mitochondria biogenesis failure. Here, we investigated the assembly, structure and function of thermic aggregates/oligomers of recombinant human mortalin and Hsp70-1A (HSPA1A). Summarily, both Hsp70 thermic aggregates have characteristics of supramolecular assemblies. They display characteristic organized structures and partial ATPase activity, despite their nanometric size. Indeed, we observed that the interaction of these aggregates/oligomers with liposomes is similar to monomeric Hsp70s and, finally, they were non-toxic over neuroblastoma cells. These findings revealed that high molecular mass oligomers of mortalin and Hsp70-1A preserved some of the fundamental functions of these proteins.
Collapse
Affiliation(s)
- Vanessa T R Kiraly
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil
| | - Paulo R Dores-Silva
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil; Department of Surgery, School of Medicine University of California, La Jolla, USA
| | - Vitor H B Serrão
- Department Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - David M Cauvi
- Department of Surgery, School of Medicine University of California, La Jolla, USA
| | - Antonio De Maio
- Department of Surgery, School of Medicine University of California, 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, La Jolla, USA
| | - Júlio C Borges
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil.
| |
Collapse
|
7
|
Yu Q, Tian X, Shao L, Xu L, Dai R, Li X. Label-free proteomic strategy to compare the proteome differences between longissimus lumborum and psoas major muscles during early postmortem periods. Food Chem 2018; 269:427-435. [DOI: 10.1016/j.foodchem.2018.07.040] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 06/30/2018] [Accepted: 07/05/2018] [Indexed: 01/08/2023]
|
8
|
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.
Collapse
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
| |
Collapse
|