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Judit Olah - One of the best experts on this subject based on the ideXlab platform.
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P25, egy új agyi fehérje szerkezete és funkciója = Structure and function of a new brain-specific Protein, P25
2020Co-Authors: Judit Ovádi, Judit Olah, Istvan Horvath, Janos Kovacs, Ferenc Hudecz, Attila Lehotzky, Ferenc OroszAbstract:Kutatocsoportom az elmult 4 evben egy uj agy-specifikus feherje szerkezeti es funkcionalis jellemzeseben ert el jelentős eredmenyeket, melyeket egyreszt magas impakt faktoru nemzetkozi folyoiratokban publikaltunk, masreszt hazai es nemzetkozi konferenciakon mutattunk be. Kutatasaink targya a TPPP/P25 feherje volt, melyet a feherje funkcioja (Tubulin Polymerization Promoting Protein) es molekulatomege alapjan neveztunk el. Megallapitottuk, hogy a feherje szerkezet nelkuli, es a kulonosen rendezetlen N-terminalis szakasznak meghatarozo szerepe van a feherje funkciojaban, mely elsődlegesen a mikrotubularis rendszer dinamikajanak szabalyozasaban nyilvanul meg. A feherje N-terminalis szakaszan ERK2 Protein kinaz altali foszforilacio szinten befolyasolja a feherje aktivitasat. Ket homologjat, a p20-at es p18-at, azonositottuk, klonoztuk es jellemeztuk kulonboző szerveződesi szinteken. Megallapitottuk, hogy a TPPP feherjek tubulinnal valo kolcsonhatasahoz alapvető jelentősegű az egesz feherjere jellemző "unfolded" karakter. Bizonyitottuk, hogy a TPPP/P25 felhalmozodik agyszoveti zarvanytestekben, melyek a szinukleionopatiak eseten alakulnak ki. Olyan antitesteket allitottunk elő, melyek specifikusan jelzik a normal agyszoveti sejteket illetve a zarvanytesteket, ami rendkivuli jelentőseggel bir human patologiai kutatasokban, valamint biomarkerkent szolgalhat idegrendszeri korkepek azonositasara. | My research group was succeeded in the characterization of a new brain-specific Protein in the last 4 years; the results were reported, in international journals with high impact factor and in national and international conferences. The objective of our work was the TPPP/P25 Protein, which we denoted to Tubulin Polymerization Promoting Protein on the basis of its function. We showed that this Protein did not have well-defined 3D structure; the unfolded N-terminal segment displayed dominant role in the Protein function which was primarily manifested itself in the regulation of the dynamics of microtubule system. The phosphorylation of the N-terminal part by ERK2 Protein kinase plays important role in this regulation of TPPP/P25 function. We identified and cloned two homologues of TPPP/P25. We revealed that the flexibility of the TPPP/P25 was required to express its effect on the dynamics of the microtubule system. We provided evidence that TPPP/P25 was enriched in the inclusions of brain tissues characteristic for synucleinopathies. We raised specific antibodies in rats which immunostained normal brain tissues or inclusions that could be apply in human pathological research, and they could serve as biomarkers for identification of neurodegenerative diseases.
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Zinc-induced structural changes of the disordered tppp/P25 inhibits its degradation by the proteasome
Biochimica et Biophysica Acta, 2014Co-Authors: Attila Lehotzky, Judit Olah, Sándor Szunyogh, Adél Szabó, Timea Berki, Judit OvádiAbstract:Abstract Tubulin Polymerization Promoting Protein/P25 (TPPP/P25), a neomorphic moonlighting Protein displaying both physiological and pathological functions, plays a crucial role in the differentiation of the zinc-rich oligodendrocytes, the major constituent of myelin sheath; and it is enriched and co-localizes with α-synuclein in brain inclusions hallmarking Parkinson's disease and other synucleinopathies. In this work we showed that the binding of Zn2 + to TPPP/P25 promotes its dimerization resulting in increased tubulin polymerization promoting activity. We also demonstrated that the Zn2 + increases the intracellular TPPP/P25 level resulting in a more decorated microtubule network in CHO10 and CG-4 cells expressing TPPP/P25 ectopically and endogenously, respectively. This stabilization effect is crucial for the differentiation and aggresome formation under physiological and pathological conditions, respectively. The Zn2 +-mediated effect was similar to that produced by treatment of the cells with MG132, a proteasome inhibitor or Zn2 + plus MG132 as quantified by cellular ELISA. The enhancing effect of zinc ion on the level of TPPP/P25 was independent of the expression level of the Protein produced by doxycycline induction at different levels or inhibition of the Protein synthesis by cycloheximide. Thus, we suggest that the zinc as a specific divalent cation could be involved in the fine-tuning of the physiological TPPP/P25 level counteracting both the enrichment and the lack of this Protein leading to distinct central nervous system diseases.
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Zn2+-Induced Rearrangement of the Disordered TPPP/P25 Affects Its Microtubule Assembly and GTPase Activity
Biochemistry, 2011Co-Authors: Ágnes Zotter, Judit Olah, Emma Hlavanda, Andrea Bodor, András Perczel, Krisztián Szigeti, Judit Fidy, Judit OvádiAbstract:Tubulin polymerization promoting Protein/P25 (TPPP/P25) modulates the dynamics and stability of the microtubule system and plays crucial role in the myelination of oligodendrocytes. Here we showed by CD, fluorescence, and NMR spectroscopies that Zn2+ is the first ligand that induces considerable rearrangement of the disordered TPPP/P25. Zinc finger motif (His2Cys2) (His61-Cys83) was identified within the flexible region of TPPP/P25 straddled by extended unstructured N- and C-terminal regions. The specific binding of the Zn2+ to TPPP/P25 induced the formation of molten globule but not that of a well-defined tertiary structure. The Zn2+-induced partially folded structure accommodating the zinc binding motif is localized at the single Trp76-containing region as demonstrated by fluorescence resonance energy transfer and quenching experiments. We showed that the Zn2+-induced change in the TPPP/P25 structure modified its interaction with tubulin and GTP coupled with functional consequences: the TPPP/P25-promote...
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interactions of pathological hallmark Proteins tubulin polymerization promoting Protein P25 β amyloid and α synuclein
Journal of Biological Chemistry, 2011Co-Authors: Judit Olah, Orsolya Vincze, Dezső P Virok, Dora Simon, Zsolt Bozso, Natalia Tőkesi, Istvan Horvath, Emma Hlavanda, Janos Kovacs, Anna MagyarAbstract:The disordered tubulin polymerization promoting Protein (TPPP/P25) was found to be co-enriched in neuronal and glial inclusions with α-synuclein in Parkinson disease and multiple system atrophy, respectively; however, co-occurrence of α-synuclein with β-amyloid (Aβ) in human brain inclusions has been recently reported, suggesting the existence of mixed type pathologies that could result in obstacles in the correct diagnosis and treatment. Here we identified TPPP/P25 as an interacting partner of the soluble Aβ oligomers as major risk factors for Alzheimer disease using ProtoArray human Protein microarray. The interactions of oligomeric Aβ with Proteins involved in the etiology of neurological disorders were characterized by ELISA, surface plasmon resonance, pelleting experiments, and tubulin polymerization assay. We showed that the Aβ42 tightly bound to TPPP/P25 (Kd = 85 nm) and caused aberrant Protein aggregation by inhibiting the physiologically relevant TPPP/P25-derived microtubule assembly. The pair-wise interactions of Aβ42, α-synuclein, and tubulin were found to be relatively weak; however, these three components formed soluble ternary complex exclusively in the absence of TPPP/P25. The aggregation-facilitating activity of TPPP/P25 and its interaction with Aβ was monitored by electron microscopy with purified Proteins by pelleting experiments with cell-free extracts as well as by confocal microscopy with CHO cells expressing TPPP/P25 or amyloid. The finding that the interaction of TPPP/P25 with Aβ can produce pathological-like aggregates is tightly coupled with unusual pathology of the Alzheimer disease revealed previously; that is, partial co-localization of Aβ and TPPP/P25 in the case of diffuse Lewy body disease with Alzheimer disease.
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Interactions of Pathological Hallmark Proteins TUBULIN POLYMERIZATION PROMOTING Protein/P25, β-AMYLOID, AND α-SYNUCLEIN
Journal of Biological Chemistry, 2011Co-Authors: Judit Olah, Orsolya Vincze, Dezső P Virok, Dora Simon, Zsolt Bozso, Natalia Tőkesi, Istvan Horvath, Emma Hlavanda, Janos Kovacs, Anna MagyarAbstract:The disordered tubulin polymerization promoting Protein (TPPP/P25) was found to be co-enriched in neuronal and glial inclusions with α-synuclein in Parkinson disease and multiple system atrophy, respectively; however, co-occurrence of α-synuclein with β-amyloid (Aβ) in human brain inclusions has been recently reported, suggesting the existence of mixed type pathologies that could result in obstacles in the correct diagnosis and treatment. Here we identified TPPP/P25 as an interacting partner of the soluble Aβ oligomers as major risk factors for Alzheimer disease using ProtoArray human Protein microarray. The interactions of oligomeric Aβ with Proteins involved in the etiology of neurological disorders were characterized by ELISA, surface plasmon resonance, pelleting experiments, and tubulin polymerization assay. We showed that the Aβ42 tightly bound to TPPP/P25 (Kd = 85 nm) and caused aberrant Protein aggregation by inhibiting the physiologically relevant TPPP/P25-derived microtubule assembly. The pair-wise interactions of Aβ42, α-synuclein, and tubulin were found to be relatively weak; however, these three components formed soluble ternary complex exclusively in the absence of TPPP/P25. The aggregation-facilitating activity of TPPP/P25 and its interaction with Aβ was monitored by electron microscopy with purified Proteins by pelleting experiments with cell-free extracts as well as by confocal microscopy with CHO cells expressing TPPP/P25 or amyloid. The finding that the interaction of TPPP/P25 with Aβ can produce pathological-like aggregates is tightly coupled with unusual pathology of the Alzheimer disease revealed previously; that is, partial co-localization of Aβ and TPPP/P25 in the case of diffuse Lewy body disease with Alzheimer disease.
Danuše Jandová - One of the best experts on this subject based on the ideXlab platform.
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Granulocytic Protein P25 is a DNA-binding subunit of Protein Mr = 50,000: Subcellular localization, cell and species specificity
The International Journal of Biochemistry & Cell Biology, 1996Co-Authors: Pavel čabart, Ivan Kalousek, Danuše JandováAbstract:Abstract We have previously reported the presence and isolation of the novel Protein M r = 25,000 (P25) from human granulocytes. In this study, the Protein P25 was characterized by its: (a) ability to bind DNA, (b) subunit association, (c) partial Protein sequencing, (d) subcellular localization, (e) cellular and species specificity and (f) stability in the presence of released granulocytic Proteinases. For the detection of P25 in various extracts, fractions and types of human or animal hematopoietic cells, SDS-PAGE/Western blotting and immunohistochemical staining were used. The Protein P25 was subjected to N-terminal amino acid sequence analysis. Protein P25-DNA interactions were monitored using Southwestern blotting. Selective inhibition of granulocytic Proteinases was performed. Granulocytic Protein P25 was found to be a product of oxidative cleavage of disulfide bridges in the p50 dimer. It was shown that neither Protein p50 nor the P25 subunit is a degradation product of a Protein of higher molecular weight. The N-terminal amino acid sequence of P25 was: RLNYNKPHAA. Binding capacity for double stranded DNA without significant sequence specificity was revealed and nuclear localization of some fraction of p50 dimer was established. The data concerning the cell and species specificity demonstrated that the Protein is expressed only in normal human granulocytes. In summary, Protein P25 originates from splitting of the p50 dimer. This subunit shows no identity with Proteins already sequenced. DNA-binding of P25 is not sequence specific. It is concluded that the Protein p50 is localized in the nuclei and cytoplasmic granules of mature human polymorphonuclear leukocytes or granulocytes of species high on the evolutionary tree. The functions of this Protein remain to be determined.
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granulocytic Protein P25 is a dna binding subunit of Protein mr 50 000 subcellular localization cell and species specificity
The International Journal of Biochemistry & Cell Biology, 1996Co-Authors: Pavel čabart, Ivan Kalousek, Danuše JandováAbstract:Abstract We have previously reported the presence and isolation of the novel Protein M r = 25,000 (P25) from human granulocytes. In this study, the Protein P25 was characterized by its: (a) ability to bind DNA, (b) subunit association, (c) partial Protein sequencing, (d) subcellular localization, (e) cellular and species specificity and (f) stability in the presence of released granulocytic Proteinases. For the detection of P25 in various extracts, fractions and types of human or animal hematopoietic cells, SDS-PAGE/Western blotting and immunohistochemical staining were used. The Protein P25 was subjected to N-terminal amino acid sequence analysis. Protein P25-DNA interactions were monitored using Southwestern blotting. Selective inhibition of granulocytic Proteinases was performed. Granulocytic Protein P25 was found to be a product of oxidative cleavage of disulfide bridges in the p50 dimer. It was shown that neither Protein p50 nor the P25 subunit is a degradation product of a Protein of higher molecular weight. The N-terminal amino acid sequence of P25 was: RLNYNKPHAA. Binding capacity for double stranded DNA without significant sequence specificity was revealed and nuclear localization of some fraction of p50 dimer was established. The data concerning the cell and species specificity demonstrated that the Protein is expressed only in normal human granulocytes. In summary, Protein P25 originates from splitting of the p50 dimer. This subunit shows no identity with Proteins already sequenced. DNA-binding of P25 is not sequence specific. It is concluded that the Protein p50 is localized in the nuclei and cytoplasmic granules of mature human polymorphonuclear leukocytes or granulocytes of species high on the evolutionary tree. The functions of this Protein remain to be determined.
Orsolya Vincze - One of the best experts on this subject based on the ideXlab platform.
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interactions of pathological hallmark Proteins tubulin polymerization promoting Protein P25 β amyloid and α synuclein
Journal of Biological Chemistry, 2011Co-Authors: Judit Olah, Orsolya Vincze, Dezső P Virok, Dora Simon, Zsolt Bozso, Natalia Tőkesi, Istvan Horvath, Emma Hlavanda, Janos Kovacs, Anna MagyarAbstract:The disordered tubulin polymerization promoting Protein (TPPP/P25) was found to be co-enriched in neuronal and glial inclusions with α-synuclein in Parkinson disease and multiple system atrophy, respectively; however, co-occurrence of α-synuclein with β-amyloid (Aβ) in human brain inclusions has been recently reported, suggesting the existence of mixed type pathologies that could result in obstacles in the correct diagnosis and treatment. Here we identified TPPP/P25 as an interacting partner of the soluble Aβ oligomers as major risk factors for Alzheimer disease using ProtoArray human Protein microarray. The interactions of oligomeric Aβ with Proteins involved in the etiology of neurological disorders were characterized by ELISA, surface plasmon resonance, pelleting experiments, and tubulin polymerization assay. We showed that the Aβ42 tightly bound to TPPP/P25 (Kd = 85 nm) and caused aberrant Protein aggregation by inhibiting the physiologically relevant TPPP/P25-derived microtubule assembly. The pair-wise interactions of Aβ42, α-synuclein, and tubulin were found to be relatively weak; however, these three components formed soluble ternary complex exclusively in the absence of TPPP/P25. The aggregation-facilitating activity of TPPP/P25 and its interaction with Aβ was monitored by electron microscopy with purified Proteins by pelleting experiments with cell-free extracts as well as by confocal microscopy with CHO cells expressing TPPP/P25 or amyloid. The finding that the interaction of TPPP/P25 with Aβ can produce pathological-like aggregates is tightly coupled with unusual pathology of the Alzheimer disease revealed previously; that is, partial co-localization of Aβ and TPPP/P25 in the case of diffuse Lewy body disease with Alzheimer disease.
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Interactions of Pathological Hallmark Proteins TUBULIN POLYMERIZATION PROMOTING Protein/P25, β-AMYLOID, AND α-SYNUCLEIN
Journal of Biological Chemistry, 2011Co-Authors: Judit Olah, Orsolya Vincze, Dezső P Virok, Dora Simon, Zsolt Bozso, Natalia Tőkesi, Istvan Horvath, Emma Hlavanda, Janos Kovacs, Anna MagyarAbstract:The disordered tubulin polymerization promoting Protein (TPPP/P25) was found to be co-enriched in neuronal and glial inclusions with α-synuclein in Parkinson disease and multiple system atrophy, respectively; however, co-occurrence of α-synuclein with β-amyloid (Aβ) in human brain inclusions has been recently reported, suggesting the existence of mixed type pathologies that could result in obstacles in the correct diagnosis and treatment. Here we identified TPPP/P25 as an interacting partner of the soluble Aβ oligomers as major risk factors for Alzheimer disease using ProtoArray human Protein microarray. The interactions of oligomeric Aβ with Proteins involved in the etiology of neurological disorders were characterized by ELISA, surface plasmon resonance, pelleting experiments, and tubulin polymerization assay. We showed that the Aβ42 tightly bound to TPPP/P25 (Kd = 85 nm) and caused aberrant Protein aggregation by inhibiting the physiologically relevant TPPP/P25-derived microtubule assembly. The pair-wise interactions of Aβ42, α-synuclein, and tubulin were found to be relatively weak; however, these three components formed soluble ternary complex exclusively in the absence of TPPP/P25. The aggregation-facilitating activity of TPPP/P25 and its interaction with Aβ was monitored by electron microscopy with purified Proteins by pelleting experiments with cell-free extracts as well as by confocal microscopy with CHO cells expressing TPPP/P25 or amyloid. The finding that the interaction of TPPP/P25 with Aβ can produce pathological-like aggregates is tightly coupled with unusual pathology of the Alzheimer disease revealed previously; that is, partial co-localization of Aβ and TPPP/P25 in the case of diffuse Lewy body disease with Alzheimer disease.
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a new myelin Protein tppp P25 reduced in demyelinated lesions is enriched in cerebrospinal fluid of multiple sclerosis
Biochemical and Biophysical Research Communications, 2011Co-Authors: Orsolya Vincze, Judit Olah, Denes Zadori, Peter Klivenyi, Laszlo Vecsei, Judit OvádiAbstract:Abstract Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease with variable extent of remyelination coupled with the differentiation of oligodendrocytes, in which Tubulin Polymerization Promoting Protein/P25 (TPPP/P25) plays a crucial role. Previously we reported that the loss of TPPP/P25-positive oligodendrocytes in demyelinated lesions in the brain of MS patients could be a biomarker for MS [2] . In this work we tested the occurrence of TPPP/P25 in the cerebrospinal fluid (CSF) of MS patients, and by elaborating a sensitive assay for quantification of TPPP/P25 we showed that its level is significantly higher than in the case of non-MS patients. Patients with MS were diagnosed at the Department of Neurology, University of Szeged according to the clinical and laboratory diagnostic criteria of McDonald. In non-MS patients no significant pathological changes were detected on magnetic resonance imaging scans, while in MS patients multiple hyperintense T2 lesions in the white matter were detected. Kurtzke Expanded Disability Status Scale scores as well as IgG level and oligoclonal bands of MS patients were demonstrated. The sensitive assay elaborated in this study is based upon Western blot followed by chemiluminescent detection validated by human recombinant Protein. The median TPPP/P25 contents in the CSF were 62.8 and 64.7 μg/L for patients with clinically isolated syndromes and relapsing remitting MS, respectively, while this value for non-MS patients was 27.9 μg/L. The enrichment of TPPP/P25 was independent of age, gender and the time period between lumbar puncture and relapse/shub. These data suggest that the TPPP/P25-based assay could be a powerful diagnostic test for MS patients.
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Tubulin Polymerization Promoting Proteins (TPPPs): Members of a New Family with Distinct Structures and Functions†
Biochemistry, 2006Co-Authors: Orsolya Vincze, Judit Olah, Istvan Horvath, Emma Hlavanda, Ágnes Zotter, Attila Lehotzky, Natália Tökési, László Tirián, Katalin F. Medzihradszky, Janos KovacsAbstract:TPPP/P25 is a brain-specific Protein, which induces tubulin polymerization and microtubule (MT) bundling and is enriched in Lewy bodies characteristic of Parkinson's disease [Tirian et al. (2003) Proc. Natl. Acad. Sci. U.S.A. 100, 13976−13981]. We identified two human gene sequences, CG1−38 and P25β, which encoded homologous Proteins, that we termed p20 and p18, respectively. These homologous Proteins display 60% identity with tubulin polymerization promoting Protein/P25 (TPPP/P25); however, the N-terminal segment of TPPP/P25 is missing. They could be clustered into three subfamilies present in mammals and other vertebrates. We cloned, isolated, and characterized the structural and functional properties of the recombinant human Proteins at molecular, ultrastructural, and cellular levels using a number of tools. These data revealed that, while p20 behaved as a disorganized Protein similarly to TPPP/P25, which was described as a flexible and inherently dynamic Protein with a long unstructured N-terminal tai...
David Gilmer - One of the best experts on this subject based on the ideXlab platform.
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nucleo cytoplasmic shuttling of the beet necrotic yellow vein virus rna 3 encoded P25 Protein
Journal of General Virology, 2004Co-Authors: Guillaume Vetter, Jeanmichel Hily, Elodie Klein, Laure Schmidlin, Muriel Haas, Thomas Merkle, David GilmerAbstract:The Protein P25 encoded by beet necrotic yellow vein virus (BNYVV) RNA-3 is involved in symptom expression of infected plants. Confocal microscopy analysis of wild-type and mutated P25 fused to GFP and transiently expressed in BY-2 tobacco suspension cells identified a nuclear localization signal (NLS) in the N-terminal part of the Protein. Functionality of the NLS was confirmed by pull-down assays using rice and pepper importin-α. Furthermore, it was demonstrated that P25 contains a nuclear export sequence sensitive to leptomycin B. The nuclear export signal (NES) was characterized by mutagenesis. A GFP–P25 fusion Protein expressed during a BNYVV infection of Chenopodium quinoa leaves had the same subcellular localization as observed during transient expression in BY-2 cells. The symptom phenotype induced by expression of GFP–P25 during infection was similar to that induced by wild-type virus. Studies with mutated derivatives of GFP–P25 revealed that symptom phenotype was altered when the subcellular localization of GFP–P25 was modified.
C Stussigaraud - One of the best experts on this subject based on the ideXlab platform.
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in situ localization of the non structural Protein P25 encoded by beet necrotic yellow vein virus rna 3
Journal of General Virology, 1995Co-Authors: A M Haeberle, C StussigaraudAbstract:The in situ localization of the non-structural Protein P25 encoded by beet necrotic yellow vein virus (BNYVV) RNA 3 and of the BNYVV coat Protein (CP) was studied by immunoelectron microscopy in infected leaf and root cells of Chenopodium murale and C. quinoa. The CP was detected in the cytoplasm of all cell types except xylem, sieve elements, and companion cells. P25 was detected in the cytoplasm and nuclei of the same cell types. The intensity of CP labelling varied depending upon the stage of infection of the cell, whereas the P25 labelling intensity was similar in newly infected cells and in cells at later stages of infection. These results suggest that P25 may be synthesized at an earlier stage of infection than CP. Its presence in the nuclei of newly infected cells may be related to the reported effect of P25 on leaf symptom development.
