The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Alessandro Sette - One of the best experts on this subject based on the ideXlab platform.
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Differential recognition of heat-shock Protein DnaJ–derived epitopes by effector and Treg cells leads to modulation of inflammation in juvenile idiopathic arthritis
Arthritis & Rheumatism, 2020Co-Authors: Margherita Massa, Maristella Passalia, Silvia Magni Manzoni, Rita Campanelli, L Ciardelli, Gisella Puga Yung, Sylvia Kamphuis, Angela Pistorio, Valentina Meli, Alessandro SetteAbstract:Objective To identify epitopes on Escherichia coli heat-shock Protein (HSP) DnaJ or on homologous human HSP DnaJ involved in the induction/modulation of autoimmune inflammation in patients with oligoarticular juvenile idiopathic arthritis (JIA). Methods We used a proliferation assay and cytokine production to evaluate the immune responses of synovial fluid mononuclear cells (SFMCs) to pan–HLA–DR binder peptides derived from either homologous or nonhomologous regions on bacterial and human HSP DnaJ. Cytofluorometric analysis was performed in order to phenotype and sort Treg cells. Sorted cells were then analyzed for the expression of the forkhead box P3 (FoxP3) transcription factor, and their regulatory capacity was tested in coculture assays. Results T cell responses to E coli HSP DnaJ–derived peptides were eminently proinflammatory. Conversely, peptides derived from human HSP DnaJ induced interleukin-10 (IL-10) production from SFMCs of patients with oligoarticular JIA. A positive correlation was found between disease with a better prognosis (persistent oligoarticular JIA) and recognition of 3 human HSP DnaJ–derived peptides. The recognition of the human peptide H134–148 also induced a significantly greater amount of IL-10 in patients with persistent oligoarticular JIA than in those with extended oligoarticular JIA (P = 0.0012). Incubation of SFMCs from patients with persistent oligoarticular JIA with this human epitope increased the percentage of Treg cells and FoxP3 expression. It also induced the recovery of suppressor activity by Treg cells. Conclusion This is the first description of a self-regulating immune modulator circuit active during autoimmune inflammation through recognition of HSP epitopes with different functional properties. These epitopes induce T cells with regulatory function. Such induction correlates with disease severity and prognosis.
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differential recognition of heat shock Protein DnaJ derived epitopes by effector and treg cells leads to modulation of inflammation in juvenile idiopathic arthritis
Arthritis & Rheumatism, 2007Co-Authors: Margherita Massa, Maristella Passalia, Silvia Magni Manzoni, Rita Campanelli, L Ciardelli, Gisella Puga Yung, Sylvia Kamphuis, Angela Pistorio, Valentina Meli, Alessandro SetteAbstract:Objective To identify epitopes on Escherichia coli heat-shock Protein (HSP) DnaJ or on homologous human HSP DnaJ involved in the induction/modulation of autoimmune inflammation in patients with oligoarticular juvenile idiopathic arthritis (JIA). Methods We used a proliferation assay and cytokine production to evaluate the immune responses of synovial fluid mononuclear cells (SFMCs) to pan–HLA–DR binder peptides derived from either homologous or nonhomologous regions on bacterial and human HSP DnaJ. Cytofluorometric analysis was performed in order to phenotype and sort Treg cells. Sorted cells were then analyzed for the expression of the forkhead box P3 (FoxP3) transcription factor, and their regulatory capacity was tested in coculture assays. Results T cell responses to E coli HSP DnaJ–derived peptides were eminently proinflammatory. Conversely, peptides derived from human HSP DnaJ induced interleukin-10 (IL-10) production from SFMCs of patients with oligoarticular JIA. A positive correlation was found between disease with a better prognosis (persistent oligoarticular JIA) and recognition of 3 human HSP DnaJ–derived peptides. The recognition of the human peptide H134–148 also induced a significantly greater amount of IL-10 in patients with persistent oligoarticular JIA than in those with extended oligoarticular JIA (P = 0.0012). Incubation of SFMCs from patients with persistent oligoarticular JIA with this human epitope increased the percentage of Treg cells and FoxP3 expression. It also induced the recovery of suppressor activity by Treg cells. Conclusion This is the first description of a self-regulating immune modulator circuit active during autoimmune inflammation through recognition of HSP epitopes with different functional properties. These epitopes induce T cells with regulatory function. Such induction correlates with disease severity and prognosis.
Brian H. Anderton - One of the best experts on this subject based on the ideXlab platform.
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Neuronal homologues of the bacterial heat shock Protein DnaJ.
1994Co-Authors: Michael E. Cheetham, Jean Pierre Brion, Brian H. Anderton, J. Mayer, Ian R. BrownAbstract:The bacterial heat-shock Protein DnaJ has been implicated in Protein folding and Protein complex dissociation. The DnaJ Protein interacts with the prokaryotic analogue of Hsp70, DnaK, and accelerates the rate of ATP hydrolysis by DnaK. Several yeast homologues of DnaJ, with different proposed subcellular localizations and functions, have recently been isolated and are the only eukaryotic forms of DnaJ so far described. We have isolated cDNAs corresponding to two alternatively spliced transcripts of a novel human gene, HSJJ, which show sequence similarity to the bacterial DnaJ Protein and the yeast homologues. The cDNA clones were isolated from a human brain-frontal-cortex expression library screened with a polyclonal antiserum raised to paired-helical-filament (PHF) Proteins isolated from extracts of the brains of patients suffering from Alzheimer's disease. The similarity between the predicted human Protein sequences and the bacterial and yeast Proteins is highest at the N-termini, this region also shows a limited similarity to viral T-antigens and is a possible common motif involved in the interaction with DnaK/Hsp7O. Northern-blot analysis has shown that human brain contains higher levels of mRNA for the DnaJ homologue than other tissues examined, and hybridization studies with riboprobes in situ show a restricted pattern of expression of the mRNA within the brain, with neuronal layers giving the strongest signal. These findings suggest that the DnaJ-DnaK (Hsp7O) interaction is general to eukaryotes and, indeed, to higher organisms.
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human homologues of the bacterial heat shock Protein DnaJ are preferentially expressed in neurons
Biochemical Journal, 1992Co-Authors: Michael E. Cheetham, Jean Pierre Brion, Brian H. AndertonAbstract:The bacterial heat-shock Protein DnaJ has been implicated in Protein folding and Protein complex dissociation. The DnaJ Protein interacts with the prokaryotic analogue of Hsp70, DnaK, and accelerates the rate of ATP hydrolysis by DnaK. Several yeast homologues of DnaJ, with different proposed subcellular localizations and functions, have recently been isolated and are the only eukaryotic forms of DnaJ so far described. We have isolated cDNAs corresponding to two alternatively spliced transcripts of a novel human gene, HSJ1, which show sequence similarity to the bacterial DnaJ Protein and the yeast homologues. The cDNA clones were isolated from a human brain-frontal-cortex expression library screened with a polyclonal antiserum raised to paired-helical-filament (PHF) Proteins isolated from extracts of the brains of patients suffering from Alzheimer's disease. The similarity between the predicted human Protein sequences and the bacterial and yeast Proteins is highest at the N-termini, this region also shows a limited similarity to viral T-antigens and is a possible common motif involved in the interaction with DnaK/Hsp70. Northern-blot analysis has shown that human brain contains higher levels of mRNA for the DnaJ homologue than other tissues examined, and hybridization studies with riboprobes in situ show a restricted pattern of expression of the mRNA within the brain, with neuronal layers giving the strongest signal. These findings suggest that the DnaJ-DnaK (Hsp70) interaction is general to eukaryotes and, indeed, to higher organisms.
Xuemei Zhang - One of the best experts on this subject based on the ideXlab platform.
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Expression of Toll-Like Receptor 2 by Dendritic Cells Is Essential for the DnaJ-ΔA146Ply-Mediated Th1 Immune Response against Streptococcus pneumoniae
Infection and Immunity, 2017Co-Authors: Xiaofang Wang, Yufeng Su, Jun Yuan, Taixian Yuan, Jingwen Wu, Hong Zhang, Xuemei ZhangAbstract:The fusion Protein DnaJ-ΔA146Ply could induce cross-protective immunity against pneumococcal infection via mucosal and subcutaneous immunization in mice in the absence of additional adjuvants. DnaJ and Ply are both Toll-like receptor 4 (TLR4) but not TLR2 ligands. However, we found that TLR2-/- mice immunized subcutaneously with DnaJ-ΔA146Ply showed significantly lower survival rates and higher bacterial loads in nasal washes than did wild-type (WT) mice after being challenged with pneumococcal strain D39 or 19F. The gamma interferon (IFN-γ) level in splenocytes decreased in TLR2-/- mice, indicating that Th1 immunity elicited by DnaJ-ΔA146Ply was impaired in these mice. We explored the mechanism of protective immunity conferred by DnaJ-ΔA146Ply and the role of TLR2 in this process. DnaJ-ΔA146Ply effectively promoted dendritic cell (DC) maturation via TLR4 but not the TLR2 signaling pathway. In a DnaJ-ΔA146Ply-treated DC and naive CD4+ T cell coculture system, the deficiency of TLR2 in DCs resulted in a significant decline of IFN-γ production and Th1 subset differentiation. The same effect was observed in adoptive-transfer experiments. In addition, TLR2-/- DCs showed remarkably lower levels of the Th1-polarizing cytokine IL-12p70 than did WT DCs, suggesting that TLR2 was indispensable for DnaJ-ΔA146Ply-induced IL-12 production and Th1 proliferation. Thus, our findings illustrate that dendritic cell expression of TLR2 is essential for optimal Th1 immune response against pneumococci in mice immunized subcutaneously with DnaJ-ΔA146Ply.
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subcutaneous immunization with fusion Protein DnaJ δa146ply without additional adjuvants induces both humoral and cellular immunity against pneumococcal infection partially depending on tlr4
Frontiers in Immunology, 2017Co-Authors: Yufeng Su, Dagen Li, Yan Xing, Hong Wang, Jian Wang, Jun Yuan, Xiaofang Wang, Xuemei ZhangAbstract:Subunit vaccines that are poorly immunogenic are often combined with adjuvants for immunization. Our previous research identified a pneumolysin variant (∆A146Ply), a Toll - like receptor 4 agonist, that was an effective adjuvant in the protection of fusion Protein DnaJ-∆A146Ply against mucosal Streptococcus pneumoniae infections. For pneumcoccal vaccines, World Health Organization recommend injection as a regular vaccination approach. Subcutaneous immunization is a common and effective method of injection, so we explored the immunity mechanism of subcutaneous immunization with DnaJ- ∆A146Ply. We found that mice immunized subcutaneously with fusion Proteins ∆A146Ply-DnaJ and DnaJ-∆A146Ply produced a higher anti-DnaJ IgG titer than when DnaJ alone was administered. DnaJ-∆A146Ply induced both B-cell and T-cell-dependent protection against both colonization and lethal pneumococcal infections. Levels of IFN-γ, IL-4 and IL-17A were also elevated in DnaJ-∆A146Ply immunized mice. However, all these effects were negated in TLR4-/- mice compared to WT mice immunized with DnaJ-∆A146Ply. B-cell-deficient μMT mice, nude mice, IFN-γ-/- and IL-4-/- mice immunized with DnaJ-∆A146Ply could not resist infection with pneumococci. IL-17A-/- and TLR4-/- mice did not benefit from DnaJ-∆Ply immunization in colonization experiments although their survival was not impaired compared with WT mice. Collectively, our data indicated that ∆A146Ply can be a potential subcutaneous adjuvant, and the DnaJ-∆A146Ply fusion Protein induces both humoral and cellular immune response to resist S. pneumoniae infection. The protective effect of colonization also depends on TLR4.
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DnaJ (hsp40) of Streptococcus pneumoniae is involved in bacterial virulence and elicits a strong natural immune reaction via PI3K/JNK.
Molecular Immunology, 2017Co-Authors: Chenyu Ma, Jian Wang, Xuemei Zhang, Guo Ye, Wenchun Xu, Liang Zhong, Hong WangAbstract:As a heat shock Protein, DnaJ plays an important role in the pathogenesis of pneumococcal infection. However, how the virulence factor-DnaJ elicits host natural immunity still remains unclear. In this study, we investigated the effects of DnaJ deficiency in Streptococcus pneumoniae (S. pneumoniae) on bacterial virulence, and further explored the related molecular mechanisms in vivo and in vitro. By generating DnaJ deficient mutant (ΔDnaJ), the virulence and colonization were detected in murine pneumonia and sepsis models in vivo. Compared with wild-type parent strain, the abilities of rapid colonization and induction of inflammatory responses of ΔDnaJ in mouse lungs were significantly impaired. Simultaneously, recombinant DnaJ purified from E. coli expression system (rDnaJ) induced macrophage strain RAW264.7 to secrete IL-6 by activation of PI3K and JNK signal pathways, which were confirmed by the specific signaling inhibitors. In conclusion, DnaJ, a novel virulence Protein, was essential for the virulence and colonization of S. pneumoniae and induced pro-inflammatory cytokine production in macrophages through PI3K/JNK.
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mucosal immunization with recombinant fusion Protein DnaJ δa146ply enhances cross protective immunity against streptococcus pneumoniae infection in mice via interleukin 17a
Infection and Immunity, 2014Co-Authors: Hong Wang, Shuai Zhang, Lingbin Zeng, Xiuyu Xu, Kaifeng Wu, Wei Wang, Zhixin Song, Xuemei ZhangAbstract:Pneumolysin (Ply) and its variants are protective against pneumococcal infections in animal models, and as a Toll-like receptor 4 agonist, pneumolysin has been reported to be a mucosal adjuvant. DnaJ has been approved as a useful candidate vaccine Protein; we therefore designed novel fusion Proteins of DnaJ with a form of Ply that has a deletion of A146 (ΔA146Ply-DnaJ [the C terminus of ΔA146Ply connected with the N terminus of DnaJ] and DnaJ-ΔA146Ply [the C terminus of DnaJ connected with the N terminus of ΔA146Ply]) to test whether they are protective against focal and lethal pneumococcal infections and their potential protective mechanisms. The purified Proteins were used to intranasally immunize the animals without additional adjuvant. Immunization with DnaJ-ΔA146Ply or DnaJ plus ΔA146Ply (Ply with a single deletion of A146) could significantly reduce S. pneumoniae colonization in the nasopharynx and lung relative with DnaJ alone. Additionally, we observed the best protection for DnaJ-ΔA146Ply-immunized mice after challenge with lethal doses of S. pneumoniae strains, which was comparable to that achieved by PPV23. Mice immunized with DnaJ-ΔA146Ply produced significantly higher levels of anti-DnaJ IgG in serum and secretory IgA (sIgA) in saliva than those immunized with DnaJ alone. The production of IL-17A was also striking in DnaJ-ΔA146Ply-immunized mice. IL-17A knockout (KO) mice did not benefit from DnaJ-ΔA146Ply immunization in colonization experiments, and sIgA production was impaired in IL-17A KO mice. Collectively, our results indicate a mucosal adjuvant potential for ΔA146Ply and that, without additional adjuvant, DnaJ-ΔA146Ply fusion Protein exhibits extensive immune stimulation and is effective against pneumococcal challenges, properties which are partially attributed to the IL-17A-mediated immune responses.
Margherita Massa - One of the best experts on this subject based on the ideXlab platform.
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Differential recognition of heat-shock Protein DnaJ–derived epitopes by effector and Treg cells leads to modulation of inflammation in juvenile idiopathic arthritis
Arthritis & Rheumatism, 2020Co-Authors: Margherita Massa, Maristella Passalia, Silvia Magni Manzoni, Rita Campanelli, L Ciardelli, Gisella Puga Yung, Sylvia Kamphuis, Angela Pistorio, Valentina Meli, Alessandro SetteAbstract:Objective To identify epitopes on Escherichia coli heat-shock Protein (HSP) DnaJ or on homologous human HSP DnaJ involved in the induction/modulation of autoimmune inflammation in patients with oligoarticular juvenile idiopathic arthritis (JIA). Methods We used a proliferation assay and cytokine production to evaluate the immune responses of synovial fluid mononuclear cells (SFMCs) to pan–HLA–DR binder peptides derived from either homologous or nonhomologous regions on bacterial and human HSP DnaJ. Cytofluorometric analysis was performed in order to phenotype and sort Treg cells. Sorted cells were then analyzed for the expression of the forkhead box P3 (FoxP3) transcription factor, and their regulatory capacity was tested in coculture assays. Results T cell responses to E coli HSP DnaJ–derived peptides were eminently proinflammatory. Conversely, peptides derived from human HSP DnaJ induced interleukin-10 (IL-10) production from SFMCs of patients with oligoarticular JIA. A positive correlation was found between disease with a better prognosis (persistent oligoarticular JIA) and recognition of 3 human HSP DnaJ–derived peptides. The recognition of the human peptide H134–148 also induced a significantly greater amount of IL-10 in patients with persistent oligoarticular JIA than in those with extended oligoarticular JIA (P = 0.0012). Incubation of SFMCs from patients with persistent oligoarticular JIA with this human epitope increased the percentage of Treg cells and FoxP3 expression. It also induced the recovery of suppressor activity by Treg cells. Conclusion This is the first description of a self-regulating immune modulator circuit active during autoimmune inflammation through recognition of HSP epitopes with different functional properties. These epitopes induce T cells with regulatory function. Such induction correlates with disease severity and prognosis.
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differential recognition of heat shock Protein DnaJ derived epitopes by effector and treg cells leads to modulation of inflammation in juvenile idiopathic arthritis
Arthritis & Rheumatism, 2007Co-Authors: Margherita Massa, Maristella Passalia, Silvia Magni Manzoni, Rita Campanelli, L Ciardelli, Gisella Puga Yung, Sylvia Kamphuis, Angela Pistorio, Valentina Meli, Alessandro SetteAbstract:Objective To identify epitopes on Escherichia coli heat-shock Protein (HSP) DnaJ or on homologous human HSP DnaJ involved in the induction/modulation of autoimmune inflammation in patients with oligoarticular juvenile idiopathic arthritis (JIA). Methods We used a proliferation assay and cytokine production to evaluate the immune responses of synovial fluid mononuclear cells (SFMCs) to pan–HLA–DR binder peptides derived from either homologous or nonhomologous regions on bacterial and human HSP DnaJ. Cytofluorometric analysis was performed in order to phenotype and sort Treg cells. Sorted cells were then analyzed for the expression of the forkhead box P3 (FoxP3) transcription factor, and their regulatory capacity was tested in coculture assays. Results T cell responses to E coli HSP DnaJ–derived peptides were eminently proinflammatory. Conversely, peptides derived from human HSP DnaJ induced interleukin-10 (IL-10) production from SFMCs of patients with oligoarticular JIA. A positive correlation was found between disease with a better prognosis (persistent oligoarticular JIA) and recognition of 3 human HSP DnaJ–derived peptides. The recognition of the human peptide H134–148 also induced a significantly greater amount of IL-10 in patients with persistent oligoarticular JIA than in those with extended oligoarticular JIA (P = 0.0012). Incubation of SFMCs from patients with persistent oligoarticular JIA with this human epitope increased the percentage of Treg cells and FoxP3 expression. It also induced the recovery of suppressor activity by Treg cells. Conclusion This is the first description of a self-regulating immune modulator circuit active during autoimmune inflammation through recognition of HSP epitopes with different functional properties. These epitopes induce T cells with regulatory function. Such induction correlates with disease severity and prognosis.
Michael E. Cheetham - One of the best experts on this subject based on the ideXlab platform.
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Analysis of the levels of conservation of the J domain among the various types of DnaJ-like Proteins.
Cell Stress & Chaperones, 2000Co-Authors: Fritha Hennessy, Michael E. Cheetham, Heini W. Dirr, Gregory L. BlatchAbstract:DnaJ-like Proteins are defined by the presence of an approximately 73 amino acid region termed the J domain. This region bears similarity to the initial 73 amino acids of the Escherichia coli Protein DnaJ. Although the structures of the J domains of E coli DnaJ and human heat shock Protein 40 have been solved using nuclear magnetic resonance, no detailed analysis of the amino acid conservation among the J domains of the various DnaJ-like Proteins has yet been attempted. A multiple alignment of 223 J domain sequences was performed, and the levels of amino acid conservation at each position were established. It was found that the levels of sequence conservation were particularly high in ‘true’ DnaJ homologues (ie, those that share full domain conservation with DnaJ) and decreased substantially in those J domains in DnaJ-like Proteins that contained no additional similarity to DnaJ outside their J domain. Residues were also identified that could be important for stabilizing the J domain and for mediating the interaction with heat shock Protein 70.
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Neuronal homologues of the bacterial heat shock Protein DnaJ.
1994Co-Authors: Michael E. Cheetham, Jean Pierre Brion, Brian H. Anderton, J. Mayer, Ian R. BrownAbstract:The bacterial heat-shock Protein DnaJ has been implicated in Protein folding and Protein complex dissociation. The DnaJ Protein interacts with the prokaryotic analogue of Hsp70, DnaK, and accelerates the rate of ATP hydrolysis by DnaK. Several yeast homologues of DnaJ, with different proposed subcellular localizations and functions, have recently been isolated and are the only eukaryotic forms of DnaJ so far described. We have isolated cDNAs corresponding to two alternatively spliced transcripts of a novel human gene, HSJJ, which show sequence similarity to the bacterial DnaJ Protein and the yeast homologues. The cDNA clones were isolated from a human brain-frontal-cortex expression library screened with a polyclonal antiserum raised to paired-helical-filament (PHF) Proteins isolated from extracts of the brains of patients suffering from Alzheimer's disease. The similarity between the predicted human Protein sequences and the bacterial and yeast Proteins is highest at the N-termini, this region also shows a limited similarity to viral T-antigens and is a possible common motif involved in the interaction with DnaK/Hsp7O. Northern-blot analysis has shown that human brain contains higher levels of mRNA for the DnaJ homologue than other tissues examined, and hybridization studies with riboprobes in situ show a restricted pattern of expression of the mRNA within the brain, with neuronal layers giving the strongest signal. These findings suggest that the DnaJ-DnaK (Hsp7O) interaction is general to eukaryotes and, indeed, to higher organisms.
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human homologues of the bacterial heat shock Protein DnaJ are preferentially expressed in neurons
Biochemical Journal, 1992Co-Authors: Michael E. Cheetham, Jean Pierre Brion, Brian H. AndertonAbstract:The bacterial heat-shock Protein DnaJ has been implicated in Protein folding and Protein complex dissociation. The DnaJ Protein interacts with the prokaryotic analogue of Hsp70, DnaK, and accelerates the rate of ATP hydrolysis by DnaK. Several yeast homologues of DnaJ, with different proposed subcellular localizations and functions, have recently been isolated and are the only eukaryotic forms of DnaJ so far described. We have isolated cDNAs corresponding to two alternatively spliced transcripts of a novel human gene, HSJ1, which show sequence similarity to the bacterial DnaJ Protein and the yeast homologues. The cDNA clones were isolated from a human brain-frontal-cortex expression library screened with a polyclonal antiserum raised to paired-helical-filament (PHF) Proteins isolated from extracts of the brains of patients suffering from Alzheimer's disease. The similarity between the predicted human Protein sequences and the bacterial and yeast Proteins is highest at the N-termini, this region also shows a limited similarity to viral T-antigens and is a possible common motif involved in the interaction with DnaK/Hsp70. Northern-blot analysis has shown that human brain contains higher levels of mRNA for the DnaJ homologue than other tissues examined, and hybridization studies with riboprobes in situ show a restricted pattern of expression of the mRNA within the brain, with neuronal layers giving the strongest signal. These findings suggest that the DnaJ-DnaK (Hsp70) interaction is general to eukaryotes and, indeed, to higher organisms.
