Abstract 283: Redox-mediated Regulation of Histone deacetylase4, a Class II HDAC, by Thioredoxin1 through Interaction with DnaJb5, a Heat Shock Protein 40

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Tetsuro Ago ◽  
Tong Liu ◽  
Hong Li ◽  
Jeffery Molkentin ◽  
Junichi Sadoshima
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Cardiac Hypertrophy ◽  
Nuclear Localization ◽  
Nuclear Export ◽  
Pressure Overload ◽  
Class Ii ◽  
Luciferase Reporter

Thioredoxin1 (Trx1) reduces redox-sensitive proteins and regulates cell growth and death. We previously reported that cardiac hypertrophy induced by pressure-overload is suppressed in mice with cardiac specific overexpression of Trx1 (Tg-Trx1). To elucidate the mechanisms by which Trx1 suppresses cardiac hypertrophy, we performed DNA microarray analysis using Tg-Trx1 mouse hearts. We identified DnaJb5, a heat shock protein 40, as a gene significantly upregulated by Trx1. Immunostaining and immunoblot analyses indicated that Trx1 and DnaJb5 are co-localized in the nucleus of myocytes. Pull-down and immunoprecipitation assays showed that DnaJb5 interacts with TBP-2, a Trx1-binding protein. DnaJb5 did not disturb the interaction between Trx1 and TBP-2, and enhanced the Trx1 reducing activity. Both Trx1 and DnaJb5 attenuated phenylephrine (PE)-induced activation of NFAT and myocyte hypertrophy in vitro . Using transgenic mice harboring an NFAT luciferase reporter, we confirmed that Trx1 suppresses both NFAT activation and cardiac hypertrophy induced by PE in vivo . We also found that DnaJb5 binds directly to histone deacetylase 4 (HDAC4), a class II HDAC. An HDAC4 mutant lacking the minimal region responsible for the interaction with DnaJb5 (residues 628 – 881) was localized in the cytosol, in contrast to the nuclear localization of the wild-type HDAC4, suggesting the importance of the interaction for the nuclear localization of HDAC4. Overexpression of Trx1 suppressed PE-induced nuclear export of HDAC4 in myocytes. Using mass spectroscopy, we found that HDAC4 forms a disulfide bond between Cys-667 and -669, which was reduced by Trx1. The HDAC4 Cys667/669Ser mutant was localized in the cytosol, and its nuclear export was suppressed by leptomycin B, an inhibitor of exportin, suggesting that the redox modification induces nuclear export regardless of phosphorylation. Consistently, the Cys667/669Ser substitution abolished the suppressive effect of HDAC4 on NFAT activity and cardiac hypertrophy. Collectively, these results show that Trx1 upregulates DnaJb5, which recruits HDAC4 into the complex formed by Trx1-TBP-2-DnaJb5, thereby reducing HDAC4, retaining its nuclear localization, and suppressing NFAT activity and cardiac hypertrophy.

A novel function for the 90 kDa heat-shock protein (Hsp90): facilitating nuclear export of 60 S ribosomal subunits

2002 ◽  
Vol 362 (3) ◽  
pp. 675-684 ◽  
Author(s):  
Harald SCHLATTER ◽  
Thomas LANGER ◽  
Susann ROSMUS ◽  
Marie-Luise ONNEKEN ◽  
Hugo FASOLD
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Protein Interactions ◽  
Nuclear Export ◽  
Vitro Assay ◽  
Ribosomal Subunits ◽  
Cytoplasmic Proteins ◽  
Energy Dependent

Ribosomal subunits are assembled in the nucleus, and mature 40S and 60S subunits are exported stoichiometrically into the cytoplasm. The nuclear export of ribosomal subunits is a unidirectional, saturable and energy-dependent process. An in vitro assay for the nuclear export of 60S ribosomal subunits involves the use of resealed nuclear envelopes. The export of ribosomal subunits from resealed nuclear envelopes is enhanced by cytoplasmic proteins. Here we present evidence that the export-promoting activity was due to the cytoplasmic 90kDa heat-shock protein (Hsp90). Isolated, purified Hsp90 vastly enhanced the export of 60S ribosomal subunits from resealed nuclear envelopes, while inhibition of Hsp90 function, either with the Hsp90-binding drug geldanamycin or with anti-Hsp90 antibodies, resulted in reduced release of 60S ribosomal subunits. To confirm these findings under in vivo conditions, corresponding experiments were performed with Xenopus oocytes using microinjection techniques; the results obtained confirmed the findings obtained with resealed nuclear envelopes. These findings suggest that Hsp90 facilitates the nuclear export of 60S ribosomal subunits, probably by chaperoning protein interactions during the export process.

scholarly journals Επικεκαλυμμένες ενδαγγειακές προθέσεις και επαναστένωση μετά από αγγειοπλαστική

2014 ◽  
Author(s):  
Δημήτριος Λυσίτσας
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Heat Shock Protein 70 ◽  
Low Dose ◽  
High Dose ◽  
Hsp 70

Εισαγωγή: Η υπερπλασία του έσω χιτώνα παίζει μείζων ρόλο στην επαναστένωση (in-stentrestenosis). Στην παρούσα μελέτη αξιολογήσαμε in vitro την επίδραση της D-24851(κυτταροτοξική ουσία που σταματά τον κυτταρικό κύκλο στο στάδιο G2-M) στονπολλαπλασιασμό των λείων μυϊκών κυττάρων και μελετήσαμε την ασφάλεια και τηνδραστικότητα μίας ενδαγγειακής πρόθεσης (stent) επικαλυμμένης με πολυμερή ουσία πουαπελευθερώνει την D-24851, στην αναστολή της υπερπλασίας του έσω χιτώνα χωρίς ναεμποδίζει την αναγεννητική ικανότητα του ενδοθηλίου σε in vivo πειραματικό μοντέλο.Υλικό και Μέθοδοι: Γυμνά μεταλλικά stent (n=6), stent επικαλυμμένα μόνο με πολυμερήουσία (polymer-coated, n=7) και stent επικαλυμμένα με πολυμερή ουσία πουαπελευθερώνουν 31±1μg (low-dose, n=7), 216±8 μg (high-dose, n=6) ή 1774±39 μg(extreme-dose, n=5) της D-24851 εμφυτεύτηκαν στις μηριαίες αρτηρίες λευκών New Zealandκουνελιών. Τα πειραματόζωα θυσιάστηκαν στις 28 ημέρες για ιστομορφομετρική ανάλυση.Για την αξιολόγηση της ενδοθηλιακής αναγέννησης στις 90 ημέρες, 12 πειραματόζωαχρησιμοποιήθηκαν για την τοποθέτηση polymer-coated (n=3), low dose (n=3), high dose(n=3) or extreme dose (n=3) ενδαγγειακών προθέσεων.Αποτελέσματα: In vitro η D-24851 αναστέλλει την υπερπλασία των λείων μυϊκών κυττάρωνκαι επάγει την απόπτωση τους χωρίς να αυξάνει την επαγωγή της heat shock protein 70(HSP-70), μία κυτταροπροστατευτική και αντι-αποπτωτική πρωτεΐνη. Η θεραπεία με lowdoseD-24851 stents συνδυάστηκε με 38% (P=0.029) μείωση της υπερπλαστικής περιοχήςτου έσω χιτώνα και 35% (P=0.003) μείωση της επι τοις εκατό στένωσης του αυλού σεσύγκριση με τα γυμνά μεταλλικά stents. Ο τραυματισμός και η φλεγμονή του αρτηριακού τοιχώματος δεν παρουσίασαν σημαντικές διαφορές μεταξύ των ομάδων. Τα επικαλυμμέναμόνο με πολυμερή ουσία stents εμφάνισαν παρόμοια ανάπτυξη νεοιστού σε σύγκριση με ταγυμνά μεταλλικά stents. Ωστόσο, όλες οι ομάδες των stents με D-24851 παρουσίασαν ατελήενδοθηλιοποίηση συγκρινόμενα με τα polymer-coated stents.Συμπεράσματα: Οι επικεκαλυμμένες ενδαγγειακές προσθέσεις με πολυμερή ουσία καιχαμηλη δόση D-24851 μειώνουν σημαντικά την υπερπλασιά του έσω χιτώνα. Λόγω τηςατελούς ενδοθηλιοποίησης, μακράς διάρκειας μελέτες είναι απαραίτητες για ναπιστοποιήσουν ότι η αναστολή του νεοιστού παραμένει και μετά τις 28 ημέρες.

scholarly journals A 70-Kilodalton Recombinant Heat Shock Protein ofCandida albicans Is Highly Immunogenic and Enhances Systemic Murine Candidiasis

1998 ◽  
Vol 66 (5) ◽  
pp. 2154-2162 ◽  
Author(s):  
Carla Bromuro ◽  
Roberto La Valle ◽  
Silvia Sandini ◽  
Francesca Urbani ◽  
Clara M. Ausiello ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Mononuclear Cells ◽  
Cell Mediated Immunity ◽  
Healthy Human ◽  
Peripheral Blood Mononuclear ◽  
Necrosis Factor Alpha ◽  
Ifn Γ

ABSTRACT The 70-kDa recombinant Candida albicans heat shock protein (CaHsp70) and its 21-kDa C-terminal and 28-kDa N-terminal fragments (CaHsp70-Cter and CaHsp70-Nter, respectively) were studied for their immunogenicity, including proinflammatory cytokine induction in vitro and in vivo, and protection in a murine model of hematogenous candidiasis. The whole protein and its two fragments were strong inducers of both antibody (Ab; immunoglobulin G1 [IgG1] and IgG2b were the prevalent isotypes) and cell-mediated immunity (CMI) responses in mice. CaHsp70 preparations were also recognized as CMI targets by peripheral blood mononuclear cells of healthy human subjects. Inoculation of CaHsp70 preparations into immunized mice induced rapid production of interleukin-6 (IL-6) and tumor necrosis factor alpha, peaking at 2 to 5 h and declining within 24 h. CaHsp70 and CaHsp70-Cter also induced gamma interferon (IFN-γ), IL-12, and IL-10 but not IL-4 production by CD4+ lymphocytes cocultured with splenic accessory cells from nonimmunized mice. In particular, the production of IFN-γ was equal if not superior to that induced in the same cells by whole, heat-inactivated fungal cells or the mitogenic lectin concanavalin A. In immunized mice, however, IL-4 but not IL-12 was produced in addition to IFN-γ upon in vitro stimulation of CD4+ cells with CaHsp70 and CaHsp70-Cter. These animals showed a decreased median survival time compared to nonimmunized mice, and their mortality was strictly associated with organ invasion by fungal hyphae. Their enhanced susceptibility was attributable to the immunization state, as it did not occur in congenitally athymic nude mice, which were unable to raise either Ab or CMI responses to CaHsp70 preparations. Together, our data demonstrate the elevated immunogenicity of CaHsp70, with which, however, no protection against but rather some enhancement of Candida infection seemed to occur in the mouse model used.

A77 1726 (leflunomide) blocks and reverses cardiac hypertrophy and fibrosis in mice

2018 ◽  
Vol 132 (6) ◽  
pp. 685-699 ◽  
Author(s):  
Zhen-Guo Ma ◽  
Xin Zhang ◽  
Yu-Pei Yuan ◽  
Ya-Ge Jin ◽  
Ning Li ◽  
...  
Keyword(s):  
T Cell ◽  
Cardiac Hypertrophy ◽  
Protective Effect ◽  
Signaling Pathway ◽  
Cardiac Fibrosis ◽  
Pressure Overload ◽  
Akt Signaling ◽  
Akt Signaling Pathway

T-cell infiltration and the subsequent increased intracardial chronic inflammation play crucial roles in the development of cardiac hypertrophy and heart failure (HF). A77 1726, the active metabolite of leflunomide, has been reported to have powerful anti-inflammatory and T cell-inhibiting properties. However, the effect of A77 1726 on cardiac hypertrophy remains completely unknown. Herein, we found that A77 1726 treatment attenuated pressure overload or angiotensin II (Ang II)-induced cardiac hypertrophy in vivo, as well as agonist-induced hypertrophic response of cardiomyocytes in vitro. In addition, we showed that A77 1726 administration prevented induction of cardiac fibrosis by inhibiting cardiac fibroblast (CF) transformation into myofibroblast. Surprisingly, we found that the protective effect of A77 1726 was not dependent on its T lymphocyte-inhibiting property. A77 1726 suppressed the activation of protein kinase B (AKT) signaling pathway, and overexpression of constitutively active AKT completely abolished A77 1726-mediated cardioprotective effects in vivo and in vitro. Pretreatment with siRNA targetting Fyn (si Fyn) blunted the protective effect elicited by A77 1726 in vitro. More importantly, A77 1726 was capable of blocking pre-established cardiac hypertrophy in mice. In conclusion, A77 1726 attenuated cardiac hypertrophy and cardiac fibrosis via inhibiting FYN/AKT signaling pathway.

A family of related proteins is encoded by the major Drosophila heat shock gene family

1982 ◽  
Vol 2 (3) ◽  
pp. 286-292
Author(s):  
S C Wadsworth
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Heat Shock Protein ◽  
Sodium Dodecyl ◽  
Heat Shock Gene ◽  
Partial Digestion ◽  
Shock Gene ◽  
Shock Proteins

At least four proteins of 70,000 to 75,000 molecular weight (70-75K) were synthesized from mRNA which hybridized with a cloned heat shock gene previously shown to be localized to the 87A and 87C heat shock puff sites. These in vitro-synthesized proteins were indistinguishable from in vivo-synthesized heat shock-induced proteins when analyzed on sodium dodecyl sulfate-polyacrylamide gels. A comparison of the pattern of this group of proteins synthesized in vivo during a 5-min pulse or during continuous labeling indicates that the 72-75K proteins are probably not kinetic precursors to the major 70K heat shock protein. Partial digestion products generated with V8 protease indicated that the 70-75K heat shock proteins are closely related, but that there are clear differences between them. The partial digestion patterns obtained from heat shock proteins from the Kc cell line and from the Oregon R strain of Drosophila melanogaster are very similar. Genetic analysis of the patterns of 70-75K heat shock protein synthesis indicated that the genes encoding at least two of the three 72-75K heat shock proteins are located outside of the major 87A and 87C puff sites.

scholarly journals Expression and Localization Patterns of a Small Heat Shock Protein that Interacts with the Helicase Domain of Cucumber Green Mottle Mosaic Virus

2019 ◽  
Vol 109 (9) ◽  
pp. 1648-1657
Author(s):  
Shanshan Liu ◽  
Lifeng Liu ◽  
Miguel A. Aranda ◽  
Bin Peng ◽  
Qinsheng Gu
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Mosaic Virus ◽  
Defense Mechanisms ◽  
Citrullus Lanatus ◽  
Small Heat Shock Protein ◽  
Helicase Domain ◽  
Rna Accumulation

Cucumber green mottle mosaic virus (CGMMV), a member of the genus Tobamovirus (family Virgaviridae), is an economically important virus that has detrimental effects on cucurbit crops worldwide. Understanding the interaction between host factors and CGMMV viral proteins will facilitate the design of new strategies for disease control. In this study, a yeast two-hybrid assay revealed that the CGMMV helicase (HEL) domain interacts with a Citrullus lanatus small heat shock protein (sHSP), and we verified this observation by performing in vitro GST pull-down and in vivo coimmunoprecipitation assays. Measurement of the levels of accumulated sHSP transcript revealed that sHSP is upregulated on initial CGMMV infection in both Nicotiana benthamiana and C. lanatus plants, although not in the systemically infected leaves. We also found that the subcellular localization of the sHSP was altered after CGMMV infection. To further validate the role of sHSP in CGMMV infection, we produced and assayed N. benthamiana transgenic plants with up- and down-regulated sHSP expression. Overexpression of sHSP inhibited viral RNA accumulation and retarded disease development, whereas sHSP silencing had no marked effect on CGMMV infection. Therefore, we postulate that the identified sHSP may be one of the factors modulating host defense mechanisms in response to CGMMV infection and that the HEL domain interaction may inhibit this sHSP function to promote viral infection.

Sign in / Sign up

Export Citation Format

Share Document