Search results for "Hsp"
showing 10 items of 557 documents
Specific and promiscuous functions of multiple DnaJ proteins in Synechocystis sp. PCC 6803
2011
Cyanobacterial genomes typically encode multiple Hsp70 (DnaK) and Hsp40 (DnaJ) chaperones, and in the genome of the cyanobacteriumSynechocystisPCC 6803, three DnaK proteins are encoded together with seven DnaJ proteins. While only two of the DnaJ proteins can complement the growth defect of anEscherichia coliΔdnaJstrain, only disruption of thednaJgenesll0897resulted in a growth defect at elevated temperatures. Based on the domain structure and the phenotype observed following disruption of the encoding gene, Sll0897 can be classified as a canonical heat-shock protein inSynechocystis. Furthermore, mostdnaJgenes could be deleted individually, whereas disruption of the gene encoding the DnaJ S…
Diagnosis of sublethal stress in the marine sponge Geodia cydonium: application of the 70 kDa heat-shock protein and a novel biomarker, the Rab GDP d…
1997
Abstract Sponges (Porifera) are among the major phyla inhabiting the marine hard-substrate benthos, both in respect to the number of species and their biomass. Hence reliable biomarkers need to be developed to monitor the environmental load in those animals. Recently, the cDNA for the heat shock protein HSP70 has been isolated from the sponge Geodia cydonium and found to be a reliable indicator for temperature stress. In the present study, we have isolated the Rab GDP-dissociation inhibitor (GDI), which has previously been shown to be a key element in the intracellular traffic system. The 1521 bp long cDNA, encoding sponge GDI, has been isolated and analyzed. The deduced aa sequence ( M r =…
Identification of the plant compound geraniin as a novel Hsp90 inhibitor
2013
Besides its function in normal cellular growth, the molecular chaperone heat shock protein 90 (Hsp90) binds to a large number of client proteins required for promoting cancer cell growth and/or survival. In an effort to discover new small molecules able to inhibit the Hsp90 ATPase and chaperoning activities, we screened, by a surface plasmon resonance assay, a small library including different plant polyphenols. The ellagitannin geraniin, was identified as the most promising molecule, showing a binding affinity to Hsp90α similar to that of 17-(allylamino)-17-demethoxygeldanamycin (17AGG). Geraniin was able to inhibit in vitro the Hsp90α ATPase activity in a dose−dependent manner, with an in…
Stress-70 proteins in marine mussel Mytilus galloprovincialis as biomarkers of environmental pollution: a field study.
2004
In the present work we have investigated levels of stress-70 proteins in the gills of mussel Mytilus galloprovincialis collected seasonally from subtidal rocky shores at 6 different sites of the Rovinj coastal area (Northern Adriatic, Croatia). 1-D analysis (SDS-PAGE) using monoclonal mouse antibodies anti-HSP70 detected two bands of stress-70 proteins, 70 and 72 kDa constitutively present during the year. 2-D analysis (IEF+SDS-PAGE) proved that the antibodies used detected HSP70 (pI 5.7–5.9) and HSP72 (pI 5.5–5.6). The quantification of stress-70 proteins was possible using 200 ng of external HSP70 protein standard included on every blot. Maximal levels of HSP72 and HSP70 were observed in …
The effects of treated effluents on the intensity of papillomatosis and HSP70 expression in roach.
2008
Epidermal papillomatosis in fish has been proposed as an indicator of environmental stress but experimental evidence of connection between contaminants and papillomatosis in fish is scarce. We studied changes in the intensity of epidermal papillomatosis and the expression of heat shock protein 70 (HSP70) in roach, Rutilus rutilus, exposed to treated pulp mill and municipal effluents. In male roach, the increase in papillomatosis intensity was higher in fish exposed to 15% than in fish exposed to 1.5% concentration of municipal effluent. No differences were observed in papillomatosis development in females, or in HSP70 expression. In all the experiments conducted, the increasing effect of ef…
Transanal coloanal anastomosis for Hirschsprung's disease: comparison between endorectal and perirectal pull-through procedures.
2006
Le but de cette etude est de comparer les resultats de 2 techniques chirurgicales d'abaissement transanal par voie perineale pour maladie de Hirschsprung de forme recto-sigmoidienne. Materiel et Methode: Vingt-et-un patients porteurs de maladie de Hirschsprung de forme recto-sigmoidienne ont ete consecutivement operes entre novembre 1999 et avril 2003 dans les services de Chirurgie Pediatrique de Dijon et Strasbourg. Les 21 enfants ont ete operes par voie perineale transanale: Douze d'entre eux ont eu une dissection peri-rectale (TPR) et 9 une endorectale type Soave (TER). Les 2 groupes de patients ont ete compares pour la longueur du segment aganglionnaire, l'âge et le poids au moment de l…
Concomitant cellular expression of heat shock regulated genes of hepatitis B virus surface antigen and of human growth hormone by a NIH-3T3 cell line.
1993
A plasmid carrying a DNA fragment of hepatitis B virus, coding for the pre-S2 and the entire S region of the surface antigen (HBsAg), placed under the control of the promoter of the human 70 kDa heat shock protein gene (hsp70), was introduced into Line 6, a recombinant cell line that was selected from NIH-3T3 cells previously transfected with a similar construct coding for the human growth hormone cDNA gene (chGH) and with the plasmid pEJ carrying the Ha-rasEJ activated cellular oncogene. The resulting cell line, EMS8, expressed: (1) hsp70/HBsAg and hsp70/hGH hybrid genes, (2) the human Ha-rasEJ oncogene, and (3) the neomycin resistance gene, the two last plasmid markers being used for cell…
Exosomal Hsp60 levels and related miRNA in brain tumor cells
2018
One of the many pathologic conditions still without a satisfactory solution is that of brain tumors. The prognosis is poor even after surgical resection followed by post-operatory chemo- and radio-therapie (1). It is, therefore, cogent to find innovative treatment tools. Three recent developments may provide elements to discover novel treatment strategies and means. These developments are: the discovery that molecular chaperones can be determinant factors in the process of tumorigenesis (2); the elucidation of the role of miRNAs in gene regulation and determination of protein functions, including molecular chaperones; in the various cell compartments (3);the increasing understanding and cha…
Modulazione In vivo dell’Hsp70 negli emociti di Rhynchophorus ferrugineus dopo trattamento con Bacillus thuringiensis
2011
Diversi tipi di stress ambientali possono indurre l’espressione delle Hsps vengono rapidamente sintetizzate all'interno delle cellule dopo esposizione ad uno stressor. Le HSPs sono raggruppate in diverse famiglie in base alle dimensioni delle proteine. Nella maggior parte degli organismi ci sono diversi geni che codificano i membri di questa famiglia HSP. In studi precedenti è stata valutata l'interazione tra Bacillus thuringiensis e gli emociti circolanti di Rhynchophorus ferrugineus il punteruolo rosso delle palme. Questo coleottero è grande, da due a cinque centimetri di lunghezza, ed è di colore rosso ruggine, le sue larve scavano buche fino a un metro lungo il tronco delle palme, e può…
HSP90 in ageing progression and ageing related diseases
2014
HSP90 activities decline during ageing. Noteworthy, HSP90 mediated retrotransposon silencing seems to have a key role in the maintenance of genome integrity. Furthermore, inhibition of HSP90 activities lead to cell senescence and apoptosis. Original bioinformatics analyses and literature data will be discussed in the light of the potential involvement of HSP90 in ageing progression and ageing related diseases.