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Mario D. Galigniana - One of the best experts on this subject based on the ideXlab platform.
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role of mitochondrial heat shock proteins and immunophilins in neuro degenerative diseases
Current Drug Targets, 2020Co-Authors: Cristina Daneribecerra, Gisela I. Mazaira, Sol M Ciucci, Mario D. GalignianaAbstract:Pathophysiologic conditions of neurodegenerative diseases are unquestionably related to protein misfolding. The accumulation of misfolded proteins into relatively ordered structures such as fibrillar intracellular and extracellular amyloids results in tissue lesions that lead to neuronal loss and brain damage. In these pathologies, the occurrence of protein aggregates suggests certain inefficient or insufficient cellular response of those molecular chaperones that should properly assist the folding of the client proteins. In this regard, all the experimental models for neurodegenerative diseases have demonstrated that the overexpression of molecular chaperones provide effective neuroprotection. A subset of these molecular chaperones corresponds to a group of proteins that exhibit Peptidylprolyl Isomerase enzymatic activity, the immunophilins. Most of the family members of the latter group were first described as responsible of the immunosuppressive response or they were reported as members of the chaperone complex associated with HSP90 in steroid receptor oligomers. In this article we review some aspects of the liaison between molecular chaperones and neurodegenerative diseases, in particular heat-shock proteins and immunophilins with demonstrated influence in the proper function of mitochondria. This article is intended to address a field that represents a yet critical unmet clinical need for the development of neuroprotective molecules focused on potentially novel molecular targets.
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biological actions of the hsp90 binding immunophilins fkbp51 and fkbp52
Biomolecules, 2019Co-Authors: Nadia R Zgajnar, Alejandra G. Erlejman, Sonia A De Leo, Graciela Piwienpilipuk, Cecilia M Lotufo, Mario D. GalignianaAbstract:Immunophilins are a family of proteins whose signature domain is the Peptidylprolyl-Isomerase domain. High molecular weight immunophilins are characterized by the additional presence of tetratricopeptide-repeats (TPR) through which they bind to the 90-kDa heat-shock protein (Hsp90), and via this chaperone, immunophilins contribute to the regulation of the biological functions of several client-proteins. Among these Hsp90-binding immunophilins, there are two highly homologous members named FKBP51 and FKBP52 (FK506-binding protein of 51-kDa and 52-kDa, respectively) that were first characterized as components of the Hsp90-based heterocomplex associated to steroid receptors. Afterwards, they emerged as likely contributors to a variety of other hormone-dependent diseases, stress-related pathologies, psychiatric disorders, cancer, and other syndromes characterized by misfolded proteins. The differential biological actions of these immunophilins have been assigned to the structurally similar, but functionally divergent enzymatic domain. Nonetheless, they also require the complementary input of the TPR domain, most likely due to their dependence with the association to Hsp90 as a functional unit. FKBP51 and FKBP52 regulate a variety of biological processes such as steroid receptor action, transcriptional activity, protein conformation, protein trafficking, cell differentiation, apoptosis, cancer progression, telomerase activity, cytoskeleton architecture, etc. In this article we discuss the biology of these events and some mechanistic aspects.
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nf κb transcriptional activity is modulated by fk506 binding proteins fkbp51 and fkbp52 a role for peptidyl prolyl Isomerase activity
Journal of Biological Chemistry, 2014Co-Authors: Alejandra G. Erlejman, Maria Fernanda Camisay, Mario D. Galigniana, Gisela I. Mazaira, Marc B. Cox, Sonia A De Leo, Alejandro M Molinari, Vanina Fontana, Graciela PiwienpilipukAbstract:Hsp90 binding immunophilins FKBP51 and FKBP52 modulate steroid receptor trafficking and hormone-dependent biological responses. With the purpose to expand this model to other nuclear factors that are also subject to nuclear-cytoplasmic shuttling, we analyzed whether these immunophilins modulate NF-κB signaling. It is demonstrated that FKBP51 impairs both the nuclear translocation rate of NF-κB and its transcriptional activity. The inhibitory action of FKBP51 requires neither the Peptidylprolyl-Isomerase activity of the immunophilin nor its association with Hsp90. The TPR domain of FKBP51 is essential. On the other hand, FKBP52 favors the nuclear retention time of RelA, its association to a DNA consensus binding sequence, and NF-κB transcriptional activity, the latter effect being strongly dependent on the Peptidylprolyl-Isomerase activity and also on the TPR domain of FKBP52, but its interaction with Hsp90 is not required. In unstimulated cells, FKBP51 forms endogenous complexes with cytoplasmic RelA. Upon cell stimulation with phorbol ester, the NF-κB soluble complex exchanges FKBP51 for FKBP52, and the NF-κB biological effect is triggered. Importantly, FKBP52 is functionally recruited to the promoter region of NF-κB target genes, whereas FKBP51 is released. Competition assays demonstrated that both immunophilins antagonize one another, and binding assays with purified proteins suggest that the association of RelA and immunophilins could be direct. These observations suggest that the biological action of NF-κB in different cell types could be positively regulated by a high FKBP52/FKBP51 expression ratio by favoring NF-κB nuclear retention, recruitment to the promoter regions of target genes, and transcriptional activity.
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cyclophilin a is bound through its Peptidylprolyl Isomerase domain to the cytoplasmic dynein motor protein complex
Journal of Biological Chemistry, 2004Co-Authors: Mario D. Galigniana, Yoshihiro Morishima, Philippe Gallay, William B. PrattAbstract:Although cyclophilin A (CyP-A) is a relatively abundant small immunophilin present in the cytoplasm of all mammalian cells, its general function(s) in the absence of the immunosuppressant drug cyclosporin A is not known. In contrast, the high molecular weight hsp90-binding immunophilins appear to play a role in protein trafficking in that they have been shown to link glucocorticoid receptor-hsp90 and p53.hsp90 complexes to the dynein motor protein for retrograde movement along microtubules. These immunophilins link to cytoplasmic dynein indirectly through the association of the immunophilin Peptidylprolyl Isomerase (PPIase) domain with dynamitin, a component of the dynein-associated dynactin complex (Galigniana, M. D., Harrell, J. M., O'Hagen, H. M., Ljungman, M., and Pratt, W. B. (2004) J. Biol. Chem. 279, 22483-22489). Here, we show that CyP-A exists in native heterocomplexes containing cytoplasmic dynein that can be formed in cell-free systems. Prolyl Isomerase activity is not required for forming the dynein complex, but the PPIase domain fragment of FKBP52 blocks complex formation and CyP-A binds to dynamitin in a PPIase domain-dependent manner. CyP-A heterocomplexes containing tubulin and dynein can be formed in cytosol prepared under microtubule-stabilizing conditions, and CyP-A colocalizes in mouse fibroblasts with microtubules. Colocalization with microtubules is disrupted by overexpression of the PPIase domain fragment. Thus, we conclude that CyP-A associates in vitro and in vivo with the dynein/dynactin motor protein complex and we suggest that CyP-A may perform a general function related to the binding of cargo for retrograde movement along microtubules.
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binding of hsp90 associated immunophilins to cytoplasmic dynein direct binding and in vivo evidence that the Peptidylprolyl Isomerase domain is a dynein interaction domain
Biochemistry, 2002Co-Authors: Mario D. Galigniana, Christine Radanyi, Jack Michel Renoir, Jennifer M Harrell, Patrick J Murphy, Michael Chinkers, Mingjie Zhang, William B PrattAbstract:FKBP52 is a steroid receptor-associated immunophilin that binds via a tetratricopeptide repeat (TPR) domain to hsp90. FKBP52 has also been shown to interact either directly or indirectly via its Peptidylprolyl Isomerase (PPIase) domain with cytoplasmic dynein, a motor protein involved in retrograde transport of vesicles toward the nucleus. The functional role for the PPIase domain in receptor movement was demonstrated by showing that expression of the PPIase domain fragment of FKBP52 in 3T3 cells inhibits dexamethasone-dependent nuclear translocation of a green fluorescent protein-glucocorticoid receptor chimera. Here, we show that cytoplasmic dynein is co-immunoadsorbed with two other TPR domain proteins that bind hsp90 (the cyclophilin CyP-40 and the protein phosphatase PP5). Both proteins possess PPIase homology domains, and co-immunoadsorption of cytoplasmic dynein with each is blocked by the PPIase domain fragment of FKBP52. Using purified proteins, we show that FKBP52, PP5, and the PPIase domain fragment bind directly to the intermediate chain of cytoplasmic dynein. PP5 colocalizes with both cytoplasmic dynein and microtubules, and expression of the PPIase domain fragment of FKBP52 in 3T3 cells disrupts its cytoskeletal localization. We conclude that the PPIase domains of the hsp90-binding immunophilins interact directly with cytoplasmic dynein and that this interaction with the motor protein is responsible for the microtubular localization of PP5 in vivo.
Joan C Marini - One of the best experts on this subject based on the ideXlab platform.
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absence of fkbp10 in recessive type xi osteogenesis imperfecta leads to diminished collagen cross linking and reduced collagen deposition in extracellular matrix
Human Mutation, 2012Co-Authors: Mary Ann Weis, Edward L. Mertz, Carlos Trujillo, Elena Makareeva, Sergey Leikin, David R Eyre, Joan C MariniAbstract:Recessive osteogenesis imperfecta (OI) is caused by defects in genes whose products interact with type I collagen for modification and/or folding. We identified a Palestinian pedigree with moderate and lethal forms of recessive OI caused by mutations in FKBP10 or PPIB, which encode endoplasmic reticulum resident chaperone/Isomerases FKBP65 and CyPB, respectively. In one pedigree branch, both parents carry a deletion in PPIB (c.563_566delACAG), causing lethal type IX OI in their two children. In another branch, a child with moderate type XI OI has a homozygous FKBP10 mutation (c.1271_1272delCCinsA). Proband FKBP10 transcripts are 4% of control and FKBP65 protein is absent from proband cells. Proband collagen electrophoresis reveals slight band broadening, compatible with ≈10% overmodification. Normal chain incorporation, helix folding, and collagen Tm support a minimal general collagen chaperone role for FKBP65. However, there is a dramatic decrease in collagen deposited in culture despite normal collagen secretion. Mass spectrometry reveals absence of hydroxylation of the collagen telopeptide lysine involved in cross-linking, suggesting that FKBP65 is required for lysyl hydroxylase activity or access to type I collagen telopeptide lysines, perhaps through its function as a Peptidylprolyl Isomerase. Proband collagen to organics ratio in matrix is approximately 30% of normal in Raman spectra. Immunofluorescence shows sparse, disorganized collagen fibrils in proband matrix. Hum Mutat 33:1589–1598, 2012. Published 2012 Wiley Periodicals, Inc.*
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absence of fkbp10 in recessive type xi osteogenesis imperfecta leads to diminished collagen cross linking and reduced collagen deposition in extracellular matrix
Human Mutation, 2012Co-Authors: Aileen M Barnes, Mary Ann Weis, Edward L. Mertz, Elena Makareeva, Sergey Leikin, David R Eyre, Wayne A Cabral, Carlos Gustavo Trujillo, Joan C MariniAbstract:Recessive osteogenesis imperfecta (OI) is caused by defects in genes whose products interact with type I collagen for modification and/or folding. We identified a Palestinian pedigree with moderate and lethal forms of recessive OI caused by mutations in FKBP10 or PPIB, which encode endoplasmic reticulum resident chaperone/Isomerases FKBP65 and CyPB, respectively. In one pedigree branch, both parents carry a deletion in PPIB (c.563_566delACAG), causing lethal type IX OI in their two children. In another branch, a child with moderate type XI OI has a homozygous FKBP10 mutation (c.1271_1272delCCinsA). Proband FKBP10 transcripts are 4% of control and FKBP65 protein is absent from proband cells. Proband collagen electrophoresis reveals slight band broadening, compatible with ≈10% over-modification. Normal chain incorporation, helix folding, and collagen T(m) support a minimal general collagen chaperone role for FKBP65. However, there is a dramatic decrease in collagen deposited in culture despite normal collagen secretion. Mass spectrometry reveals absence of hydroxylation of the collagen telopeptide lysine involved in cross-linking, suggesting that FKBP65 is required for lysyl hydroxylase activity or access to type I collagen telopeptide lysines, perhaps through its function as a Peptidylprolyl Isomerase. Proband collagen to organics ratio in matrix is approximately 30% of normal in Raman spectra. Immunofluorescence shows sparse, disorganized collagen fibrils in proband matrix.
Youjun Zhang - One of the best experts on this subject based on the ideXlab platform.
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reference gene selection for qrt pcr analysis in the sweetpotato whitefly bemisia tabaci hemiptera aleyrodidae
PLOS ONE, 2013Co-Authors: Rumei Li, Shaoli Wang, Nina Yang, Xin Yang, Qingjun Wu, Xiaomao Zhou, Baoyun Xu, Xuguo Zhou, Youjun ZhangAbstract:Background Accurate evaluation of gene expression requires normalization relative to the expression of reliable reference genes. Expression levels of “classical” reference genes can differ, however, across experimental conditions. Although quantitative real-time PCR (qRT-PCR) has been used extensively to decipher gene function in the sweetpotato whitefly Bemisia tabaci, a world-wide pest in many agricultural systems, the stability of its reference genes has rarely been validated. Results In this study, 15 candidate reference genes from B. tabaci were evaluated using two Excel-based algorithms geNorm and Normfinder under a diverse set of biotic and abiotic conditions. At least two reference genes were selected to normalize gene expressions in B. tabaci under experimental conditions. Specifically, for biotic conditions including host plant, acquisition of a plant virus, developmental stage, tissue (body region of the adult), and whitefly biotype, ribosomal protein L29 was the most stable reference gene. In contrast, the expression of elongation factor 1 alpha, Peptidylprolyl Isomerase A, NADH dehydrogenase, succinate dehydrogenase complex subunit A and heat shock protein 40 were consistently stable across various abiotic conditions including photoperiod, temperature, and insecticide susceptibility. Conclusion Our finding is the first step toward establishing a standardized quantitative real-time PCR procedure following the MIQE (Minimum Information for publication of Quantitative real time PCR Experiments) guideline in an agriculturally important insect pest, and provides a solid foundation for future RNA interference based functional study in B. tabaci.
William B. Pratt - One of the best experts on this subject based on the ideXlab platform.
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cyclophilin a is bound through its Peptidylprolyl Isomerase domain to the cytoplasmic dynein motor protein complex
Journal of Biological Chemistry, 2004Co-Authors: Mario D. Galigniana, Yoshihiro Morishima, Philippe Gallay, William B. PrattAbstract:Although cyclophilin A (CyP-A) is a relatively abundant small immunophilin present in the cytoplasm of all mammalian cells, its general function(s) in the absence of the immunosuppressant drug cyclosporin A is not known. In contrast, the high molecular weight hsp90-binding immunophilins appear to play a role in protein trafficking in that they have been shown to link glucocorticoid receptor-hsp90 and p53.hsp90 complexes to the dynein motor protein for retrograde movement along microtubules. These immunophilins link to cytoplasmic dynein indirectly through the association of the immunophilin Peptidylprolyl Isomerase (PPIase) domain with dynamitin, a component of the dynein-associated dynactin complex (Galigniana, M. D., Harrell, J. M., O'Hagen, H. M., Ljungman, M., and Pratt, W. B. (2004) J. Biol. Chem. 279, 22483-22489). Here, we show that CyP-A exists in native heterocomplexes containing cytoplasmic dynein that can be formed in cell-free systems. Prolyl Isomerase activity is not required for forming the dynein complex, but the PPIase domain fragment of FKBP52 blocks complex formation and CyP-A binds to dynamitin in a PPIase domain-dependent manner. CyP-A heterocomplexes containing tubulin and dynein can be formed in cytosol prepared under microtubule-stabilizing conditions, and CyP-A colocalizes in mouse fibroblasts with microtubules. Colocalization with microtubules is disrupted by overexpression of the PPIase domain fragment. Thus, we conclude that CyP-A associates in vitro and in vivo with the dynein/dynactin motor protein complex and we suggest that CyP-A may perform a general function related to the binding of cargo for retrograde movement along microtubules.
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evidence that the Peptidylprolyl Isomerase domain of the hsp90 binding immunophilin fkbp52 is involved in both dynein interaction and glucocorticoid receptor movement to the nucleus
Journal of Biological Chemistry, 2001Co-Authors: Christine Radanyi, Jack Michel Renoir, Paul R Housley, William B. PrattAbstract:Abstract We have previously shown that immunoadsorption of the FKBP52 immunophilin component of steroid receptor·hsp90 heterocomplexes is accompanied by coadsorption of cytoplasmic dynein, a motor protein involved in retrograde transport of vesicles toward the nucleus. Coimmunoadsorption of dynein is competed by an expressed fragment of FKBP52 comprising its Peptidylprolyl Isomerase (PPIase) domain (Silverstein, A. M., Galigniana, M. D., Kanelakis, K. C., Radanyi, C., Renoir, J.-M., and Pratt, W. B. (1999)J. Biol. Chem. 52, 36980–36986). Here we show that cotransfection of 3T3 cells with the FKBP52 PPIase domain and a green fluorescent protein (GFP) glucocorticoid receptor (GR) chimera inhibits dexamethasone-dependent movement of the GFP-GR from the cytoplasm to the nucleus. Cotransfection with FKBP12 does not affect GFP-GR movement. Inhibition of movement by the FKBP52 PPIase domain is abrogated in cells treated with colcemid to eliminate microtubules prior to steroid addition. After withdrawal of colcemid, microtubules reform, and PPIase inhibition of GFP-GR movement is restored. These observations are consistent with the notion that FKBP52 targets retrograde movement of the GFP-GR along microtubules by linking the receptor to the dynein motor. Here, we also show that native GR·hsp90 heterocomplexes immunoadsorbed from L cell cytosol contain dynein and that GR·hsp90 heterocomplexes assembled in reticulocyte lysate contain cytoplasmic dynein in a manner that is competed by the PPIase domain of FKBP52.
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different regions of the immunophilin fkbp52 determine its association with the glucocorticoid receptor hsp90 and cytoplasmic dynein
Journal of Biological Chemistry, 1999Co-Authors: Adam M. Silverstein, Christine Radanyi, Jack Michel Renoir, Kimon C Kanelakis, William B. PrattAbstract:Abstract FKBP52 is a high molecular mass immunophilin possessing Peptidylprolyl Isomerase (PPIase) activity that is inhibited by the immunosuppressant drug FK506. FKBP52 is a component of steroid receptor·hsp90 heterocomplexes, and it binds to hsp90 via a region containing three tetratricopeptide repeats (TPRs). Here we demonstrate by cross-linking of the purified proteins that there is one binding site for FKBP52/dimer of hsp90. This accounts for the common heterotetrameric structure of native receptor heterocomplexes being 1 molecule of receptor, 2 molecules of hsp90, and 1 molecule of a TPR domain protein. Immunoadsorption of FKBP52 from reticulocyte lysate also yields co-immunoadsorption of cytoplasmic dynein, and we show that co-immunoadsorption of dynein is competed by a fragment of FKBP52 containing its PPIase domain, but not by a TPR domain fragment that blocks FKBP52 binding to hsp90. Using purified proteins, we also show that FKBP52 binds directly to the hsp90-free glucocorticoid receptor. Because neither the PPIase fragment nor the TPR fragment affects the binding of FKBP52 to the glucocorticoid receptor under conditions in which they block FKBP52 binding to dynein or hsp90, respectively, different regions of FKBP52 must determine its association with these three proteins.
Mary Ann Weis - One of the best experts on this subject based on the ideXlab platform.
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absence of fkbp10 in recessive type xi osteogenesis imperfecta leads to diminished collagen cross linking and reduced collagen deposition in extracellular matrix
Human Mutation, 2012Co-Authors: Mary Ann Weis, Edward L. Mertz, Carlos Trujillo, Elena Makareeva, Sergey Leikin, David R Eyre, Joan C MariniAbstract:Recessive osteogenesis imperfecta (OI) is caused by defects in genes whose products interact with type I collagen for modification and/or folding. We identified a Palestinian pedigree with moderate and lethal forms of recessive OI caused by mutations in FKBP10 or PPIB, which encode endoplasmic reticulum resident chaperone/Isomerases FKBP65 and CyPB, respectively. In one pedigree branch, both parents carry a deletion in PPIB (c.563_566delACAG), causing lethal type IX OI in their two children. In another branch, a child with moderate type XI OI has a homozygous FKBP10 mutation (c.1271_1272delCCinsA). Proband FKBP10 transcripts are 4% of control and FKBP65 protein is absent from proband cells. Proband collagen electrophoresis reveals slight band broadening, compatible with ≈10% overmodification. Normal chain incorporation, helix folding, and collagen Tm support a minimal general collagen chaperone role for FKBP65. However, there is a dramatic decrease in collagen deposited in culture despite normal collagen secretion. Mass spectrometry reveals absence of hydroxylation of the collagen telopeptide lysine involved in cross-linking, suggesting that FKBP65 is required for lysyl hydroxylase activity or access to type I collagen telopeptide lysines, perhaps through its function as a Peptidylprolyl Isomerase. Proband collagen to organics ratio in matrix is approximately 30% of normal in Raman spectra. Immunofluorescence shows sparse, disorganized collagen fibrils in proband matrix. Hum Mutat 33:1589–1598, 2012. Published 2012 Wiley Periodicals, Inc.*
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absence of fkbp10 in recessive type xi osteogenesis imperfecta leads to diminished collagen cross linking and reduced collagen deposition in extracellular matrix
Human Mutation, 2012Co-Authors: Aileen M Barnes, Mary Ann Weis, Edward L. Mertz, Elena Makareeva, Sergey Leikin, David R Eyre, Wayne A Cabral, Carlos Gustavo Trujillo, Joan C MariniAbstract:Recessive osteogenesis imperfecta (OI) is caused by defects in genes whose products interact with type I collagen for modification and/or folding. We identified a Palestinian pedigree with moderate and lethal forms of recessive OI caused by mutations in FKBP10 or PPIB, which encode endoplasmic reticulum resident chaperone/Isomerases FKBP65 and CyPB, respectively. In one pedigree branch, both parents carry a deletion in PPIB (c.563_566delACAG), causing lethal type IX OI in their two children. In another branch, a child with moderate type XI OI has a homozygous FKBP10 mutation (c.1271_1272delCCinsA). Proband FKBP10 transcripts are 4% of control and FKBP65 protein is absent from proband cells. Proband collagen electrophoresis reveals slight band broadening, compatible with ≈10% over-modification. Normal chain incorporation, helix folding, and collagen T(m) support a minimal general collagen chaperone role for FKBP65. However, there is a dramatic decrease in collagen deposited in culture despite normal collagen secretion. Mass spectrometry reveals absence of hydroxylation of the collagen telopeptide lysine involved in cross-linking, suggesting that FKBP65 is required for lysyl hydroxylase activity or access to type I collagen telopeptide lysines, perhaps through its function as a Peptidylprolyl Isomerase. Proband collagen to organics ratio in matrix is approximately 30% of normal in Raman spectra. Immunofluorescence shows sparse, disorganized collagen fibrils in proband matrix.