Heat shock proteins induce pores in membranes

1990 ◽  
Vol 10 (6) ◽  
pp. 509-518 ◽  
Author(s):  
G. M. Alder ◽  
B. M. Austen ◽  
C. L. Bashford ◽  
A. Mehlert ◽  
C. A. Pasternak
Keyword(s):  
Heat Shock ◽  
Human Serum Albumin ◽  
Lipid Bilayers ◽  
Diphtheria Toxin ◽  
Planar Lipid Bilayers ◽  
Bacterial Protein ◽  
Hsp 70 ◽  
Ion Conducting ◽  
Shock Proteins ◽  
Human Heat Shock Protein

Human heat shock protein (hsp) 70 and bacterial protein groEL promote leakage of calcein from liposomes induced by human serum albumin signal peptide, by S. aureus α toxin or by diphtheria toxin. Hsp 70 and groEL, as well as two mycobacterial homologues hsp 71 and hsp 65, induce ion conducting pores across planar lipid bilayers at low or neutral pH. It is concluded that hsp induce pores in membranes and that this may contribute to their action within cells.

Morphological and molecular modifications induced by heat shock in Drosophila melanogaster embryos

Development ◽  
1983 ◽  
Vol 77 (1) ◽  
pp. 167-182
Author(s):  
Giorgio Graziosi ◽  
Franco de Cristini ◽  
Angelo di Marcotullio ◽  
Roberto Marzari ◽  
Fulvio Micali ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Heat Shock ◽  
Dna Synthesis ◽  
Histological Analysis ◽  
Developmental Stages ◽  
Early Embryo ◽  
Direct Relation ◽  
Hsp 70 ◽  
Survival Pattern ◽  
Shock Proteins

The early embryo of Drosophila melanogaster did not survive treatment at 37 °C (heat shock) for 25 min. The histological analysis of eggs treated in this way showed that the heat shock caused disintegration of nuclei and of cytoplasmic islands, displacement and swelling of nuclei and blocked mitoses. These effects were not observed in embryos treatedafter blastoderm formation. After this stage, we noticed that development was slowed down. The heat shock proteins (hsp 83,70 and 68) were, under shock, synthesized at all developmental stages. There was little or no synthesis of hsp 70 and 68 in unfertilized eggs, but synthesis increased in proportion to the number of nuclei present. Most probably, hsp 70 synthesis was directed by zygotic mRNA. DNA synthesis was not blocked by the heat shock though the overall incorporation of [3H]thymidine was substantially reduced, presumably because of the block of mitoses. We did not find a direct relation between survival pattern and hsp synthesis. We concluded that some, at least, of the heat shock genes can be activated at all developmental stages and that heat shock could be used for synchronizing mitoses.

scholarly journals Species-specific collaboration of heat shock proteins (Hsp) 70 and 100 in thermotolerance and protein disaggregation

2011 ◽  
Vol 108 (17) ◽  
pp. 6915-6920 ◽  
Author(s):  
M. Miot ◽  
M. Reidy ◽  
S. M. Doyle ◽  
J. R. Hoskins ◽  
D. M. Johnston ◽  
...  
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Hsp 70 ◽  
Species Specific ◽  
Shock Proteins

Expression of heat shock genes of Neurospora crassa: effect of hyperthermia and other stresses on mRNA levels

1988 ◽  
Vol 66 (2) ◽  
pp. 81-92 ◽  
Author(s):  
Carol A. Curle ◽  
M. Kapoor
Keyword(s):  
Heat Shock ◽  
Neurospora Crassa ◽  
Sodium Arsenite ◽  
Gene Probe ◽  
Mrna Levels ◽  
Hsp 70 ◽  
Northern Blots ◽  
Stressed Cells ◽  
Shock Proteins

Neurospora crassa mycelium was heat shocked for intervals varying from 15–180 min. Heat shock mRNA was monitored by hybridization of Northern blots with the Drosophila hsp-70 gene probe and an inducible member of the yeast hsp-70 gene family, YG100. A 2.7 kilobase (kb) transcript, with homology to these two probes, was detected in cultures shocked for 15 min; its levels increased up to 60–90 min and declined thereafter. Sodium arsenite, too, induced the synthesis of this transcript. An additional, constitutively synthesized 2.4-kb transcript was revealed by hybridization with the yeast probe. The synthesis of this message was terminated during heat shock. Hybridization of Northern blots with the Drosophila actin gene probe demonstrated two size classes, 1.85 and 1.63 kb; the former decreased dramatically following heat shock. Recovery, as assessed by the disappearance of the 2.7-kb hsp-70-mRNA and restoration of the 1.85-kb actin message to the prestress levels, was essentially complete within 60 min of transfer to 28 °C. In vitro translations of RNA from stressed cells showed the heat shock messages to be stable and readily translatable. RNA of cells subjected to heat shock plus CdCl2 showed a higher content of messages for heat shock proteins of 70, 80, and 90 kilodaltons.

Interaction of Plasminogen and Angiostatin with Heat Shock Proteins.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1622-1622
Author(s):  
Anil K. Dudani ◽  
Jelica Mehic ◽  
Anthony Martyres
Keyword(s):  
Heat Shock ◽  
Heat Shock Proteins ◽  
Dependent Manner ◽  
Hsp 70 ◽  
Molar Excess ◽  
Hsp 27 ◽  
Human Plasminogen ◽  
Shock Proteins ◽  
Dose Dependent ◽  
Mcf 7

Abstract Previous studies from this laboratory have demonstrated that plasminogen and angiostatin bind to endothelial cell (EC) surface-associated actin via their kringles in a specific manner. Heat shock proteins (hsps) like hsp 27 are constitutively expressed by vascular ECs and regulate actin polymerization, cell growth and migration. Since many hsps have also been found to be highly abundant on cell surfaces and there is evidence that bacterial surface hsps may interact with human plasminogen, the purpose of this study was to determine whether human plasminogen and angiostatin would interact with human hsps. ELISAs were developed in our laboratory to assess these interactions. It was observed that plasminogen bound to hsps 27, 60 and 70. In all cases, binding was inhibited (85–90%) by excess (50 mM) lysine indicating kringle involvement. Angiostatin predominantly bound to hsp 27 and to hsp 70 in a concentration- and kringle-dependent manner. As observed previously for actin, there was dose-dependent inhibition of angiostatin’s interaction with hsp 27 by plasminogen. In addition, thirty-fold molar excess actin inhibited (up to 50%), the interaction of plasminogen with all hsps. However, thirty-fold molar excess actin could only inhibit the interaction of angiostatin with hsp 27 by 15–20%. FACS analyses indicated the presence of hsps 27, 60 and 70 on the surface of MCF-7 breast cancer cells but not on human umbilical vein ECs. Polyclonal antibodies to hsp 27 significantly inhibited the interaction of plasminogen and angiostatin with MCF-7 surface-associated hsp27 in a dose-dependent manner. Collectively, these data indicate that while plasminogen interacts specifically with hsp 27, 60 and 70, angiostatin interacts predominantly with hsp 27 and to some extent with hsp 70; plasminogen only partially displaces angiostatins binding to hsp 27; actin only partially displaces plasminogen/angiostatin binding to hsps and surface-associated hsp 27 can mediate the binding of both plasminogen and angiostatin to MCF-7 cells.

Retinoic acid stimulates the synthesis of a novel heat shock protein in the regenerating forelimb of the newt

1993 ◽  
Vol 71 (1-2) ◽  
pp. 43-50 ◽  
Author(s):  
Robert L. Carlone ◽  
Robert P. Boulianne ◽  
K. Marion Vijh ◽  
Heather Karn ◽  
Gordon A. D. Fraser
Keyword(s):  
Retinoic Acid ◽  
Heat Shock ◽  
Stress Proteins ◽  
Limb Regeneration ◽  
Stress Protein ◽  
Cross Reactivity ◽  
Hsp 70 ◽  
Peptide Map ◽  
Shock Proteins

Morphogenetic effects of retinoic acid (RA) on the urodele amphibian limb regenerate pattern have been well documented, but little is known regarding the mechanism of this action of RA at the molecular level. Since exogenous RA, at concentrations sufficient to cause proximalization, represents a significant stress to newts and has been shown previously to elicit increased synthesis of heat shock proteins (HSPs) in mouse embryo limb buds, we investigated the effects of this putative morphogen on the synthesis of members of the 70-kilodalton (70-kDa) stress protein family in amputated forelimbs of the newt Notophthalmus viridescens. Injection (i.p.) of RA in dimethyl sulfoxide (DMSO), at a dose sufficient to cause significant proximal–distal reduplication of the pattern in 50% of animals treated, resulted in increased synthesis and accumulation of a 73-kDa protein with a pi of approximately 6.75. The synthesis of this same protein is increased in limb tissues as a result of a brief 35 °C heat shock. This protein is electrophoretically distinct from the newt HSP 70 family members, displays a different partial peptide map, and shows no immunological cross-reactivity with an anti-human HSP 70 monoclonal antibody. It may be a member of a separate family of 70- to 73-kDa HSPs. Interestingly, the synthesis of this protein is increased and it is more abundant in control, proximal moderate-early bud stage regenerates at 6 days after i.p. injection of DMSO than in similarly treated distal regenerates. This protein is, in addition, increased in distal regenerates to proximal levels by a prior injection of RA. The significance of these findings with regard to the possible role of stress proteins in the morphogenetic processes underlying limb regeneration is discussed.Key words: heat shock, limb regeneration, retinoic acid, pattern formation, newt.

scholarly journals Increased Levels of Plasma Extracellular Heat-Shock Proteins 60 and 70 kDa Characterized Early-Onset Neonatal Sepsis

2021 ◽  
Vol 9 ◽  
Author(s):  
Arturo Alejandro Canul-Euan ◽  
Gibran Zúñiga-González ◽  
Janelly Estefania Palacios-Luna ◽  
Rolando Maida-Claros ◽  
Néstor Fabián Díaz ◽  
...  
Keyword(s):  
Heat Shock ◽  
Neonatal Sepsis ◽  
Predictive Value ◽  
Early Onset ◽  
C Reactive Protein ◽  
Hsp 70 ◽  
Blood Samples ◽  
Reactive Protein ◽  
Hsp 27 ◽  
Shock Proteins

Background: Extracellular heat-shock proteins (eHsp) are highly conserved molecules that play an important role in inflammatory diseases and have been quantified in plasma from patients with infectious diseases, including sepsis. There is a constant search for dependable biochemical markers that, in combination with conventional methods, could deliver a prompt and reliable diagnosis of early-onset neonatal sepsis.Objective: We sought to assess the level of eHsp-27, eHsp-60, eHsp-70, and tumor necrosis factor-alpha (TNFα) in plasma of healthy neonates at term and infants with early-onset neonatal sepsis.Methods: This study included 34 newborns that were classified as healthy neonates at term (blood samples from the umbilical cord, n = 23) or infants with early-onset neonatal sepsis (blood samples obtained from umbilical artery by standard sterile procedures before starting a systemic antibiotic intervention, n = 11). All blood samples were centrifuged, and the plasma recovered to determine eHsp-27, eHsp-60, eHsp-70, and TNFα levels by ELISA.Results: Our results indicate that the level of eHsp-27 in healthy neonates at term was 0.045 ± 0.024 pg/ml. This value decreased 2.5-fold in infants with early-onset neonate sepsis (0.019 ± 0.006 pg/ml, p = 0.004). In contrast, the levels of eHsp-60 and eHsp-70 in healthy neonates at term were 13.69 ± 5.3 and 4.03 ± 2.6 pg/ml, respectively. These protein levels increased significantly 1.8- and 1.9-fold in the plasma of infants with early-onset neonatal sepsis (p ≤ 0.001). The level of TNFα in healthy neonates at term was 2.94 ± 0.46 pg/ml, with a 3.0-fold increase in infants with early-onset neonatal sepsis (8.96 ± 0.72 pm/ml, p ≤ 0.001). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of eHsp compared with that of C-reactive protein were 73.3, 60.0, 47.8, and 33.3%, respectively.Conclusion: This study demonstrated a consistent increase of eHsp-60 and eHsp-70 in the plasma of infants diagnosed with early-onset neonatal sepsis. These proteins showed higher sensitivity and specificity than C-reactive protein and blood culture test.

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