scholarly journals Nicotine-stimulated proteins in mouse cells are distinct from heat-shock proteins

1984 ◽  
Vol 224 (1) ◽  
pp. 87-92 ◽  
Author(s):  
L A Hunt ◽  
K S Kelley

Treatment of mouse tissue-culture cells with nicotine concentrations of 1 mM or less had no significant effects on cell viability, morphology or protein synthesis, but higher concentrations resulted in both altered cell morphology (rounding and vacuolization) and alterations in [3H]leucine-labelled protein profiles on sodium dodecyl sulphate/polyacrylamide gels. The synthesis of a Mr-70 000 protein was increased more than 2-fold relative to that of other major cellular proteins in 3T3 and L929 cells treated with 5 mM-nicotine and in B16 cells treated with 10 mM-nicotine, and this protein appeared to be a soluble cytoplasmic polypeptide. The radiolabelling of several additional polypeptides (Mr 62 000 in 3T3 cells, and Mr 45 000 and 38 000 in B16 cells) was also stimulated by nicotine. The nicotine-enhanced Mr-70 000 protein was distinct, however, from a major cell stress/heat-shock protein whose synthesis was stimulated after incubation of cells at 43.5 degrees C for 20 min.

2021 ◽  
Vol 22 (5) ◽  
pp. 2591
Author(s):  
Pengfei Ma ◽  
Jie Li ◽  
Lei Qi ◽  
Xiuzhu Dong

Small heat shock proteins (sHsps) are widely distributed among various types of organisms and function in preventing the irreversible aggregation of thermal denaturing proteins. Here, we report that Hsp17.6 from Methanolobus psychrophilus exhibited protection of proteins from oxidation inactivation. The overexpression of Hsp17.6 in Escherichia coli markedly increased the stationary phase cell density and survivability in HClO and H2O2. Treatments with 0.2 mM HClO or 10 mM H2O2 reduced malate dehydrogenase (MDH) activity to 57% and 77%, whereas the addition of Hsp17.6 recovered the activity to 70–90% and 86–100%, respectively. A similar effect for superoxide dismutase oxidation was determined for Hsp17.6. Non-reducing sodium dodecyl sulfate polyacrylamide gel electrophoresis assays determined that the Hsp17.6 addition decreased H2O2-caused disulfide-linking protein contents and HClO-induced degradation of MDH; meanwhile, Hsp17.6 protein appeared to be oxidized with increased molecular weights. Mass spectrometry identified oxygen atoms introduced into the larger Hsp17.6 molecules, mainly at the aspartate and methionine residues. Substitution of some aspartate residues reduced Hsp17.6 in alleviating H2O2- and HClO-caused MDH inactivation and in enhancing the E. coli survivability in H2O2 and HClO, suggesting that the archaeal Hsp17.6 oxidation protection might depend on an “oxidant sink” effect, i.e., to consume the oxidants in environments via aspartate oxidation


1982 ◽  
Vol 2 (3) ◽  
pp. 286-292
Author(s):  
S C Wadsworth

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.


1988 ◽  
Vol 8 (1) ◽  
pp. 91-95 ◽  
Author(s):  
J Bell ◽  
L Neilson ◽  
M Pellegrini

In Drosophila tissue culture cells, the synthesis of ribosomal proteins was inhibited by a 1-h 37 degrees C heat shock. Ribosomal protein synthesis was repressed to a greater extent than that of most other proteins synthesized by these cells at 25 degrees C. After a 1-h heat shock, when the cells were returned to 25 degrees C, the ribosomal proteins were much slower than most other 25 degrees C proteins to return to pre-heat shock levels of synthesis. Relative to one another, all the ribosomal proteins were inhibited and later recovered to normal levels of synthesis at the same rate and to the same extent. Unlike the ribosomal proteins, the precursor to the large rRNAs was continually synthesized during heat shock, although at a slightly reduced level, but was not processed. It was rapidly degraded, with a half-life of approximately 16 min. Pre-heat shock levels of synthesis, stability, and correct processing were restored only when ribosomal protein synthesis returned to at least 50% of that seen in non-heat-shocked cells.


1985 ◽  
Vol 63 (7) ◽  
pp. 711-722 ◽  
Author(s):  
David Rodenhiser ◽  
Jack H. Jung ◽  
Burr G. Atkinson

Mammalian (human, mouse, and rabbit) white blood cells (lymphocytes) maintained in culture respond to a brief incubation at an elevated temperature (at or above 41 °C) by (i) the new and (or) enhanced synthesis of a small number of proteins (the so-called heat-shock proteins; HSPs) having molecular masses of approximately 110 000, 100 000, 90 000, 70 000, 65 000, and 26 000 daltons and (ii) the depressed synthesis of proteins normally made at 37 °C. The HSPs synthesized in culture by human, rabbit, and mouse (peripheral and splenic) lymphocytes are similar in number, molecular mass, and distribution on two-dimensional (isoelectric focusing and sodium dodecyl sulfate – polyacrylamide) electrophoretic gels to those synthesized in vivo by lymphocytes in hyperthermic mice. Since the level of hyperthermia used to induce HSP synthesis in mouse lymphocytes in vitro and in vivo is of a magnitude (41 °C) also used to promote thermotolerance in mice and is similar to temperatures attained during febrile episodes in rabbits and in humans, we suggest that the in vitro and in vivo synthesis of HSPs by mouse lymphocytes, demonstrated in this study, represents a relevant, physiological response which mammalian lymphocytes may normally use to survive periods of thermal stress.


1982 ◽  
Vol 2 (3) ◽  
pp. 267-274
Author(s):  
P M Kelley ◽  
M J Schlesinger

Three of the proteins induced by heat shock of chicken embryo fibroblasts have been purified, and rabbit antibodies have been raised against them. These antibodies have been used in radioimmune precipitation reactions and in a solid-phase immune assay to detect antigenic material in non-heat-shocked chicken tissues and in extracts of widely different species ranging from yeast to mammalian tissue culture cells and human erythrocyte ghosts. Antibodies to two of the major chicken heat shock proteins, chsp89 and chsp70, cross-reacted with proteins of similar molecular weights in normal embryonic and adult chicken tissues and in extracts from widely different organisms. These data provide further evidence for the university of the heat shock response and conservation of proteins induced by this type of stress.


1985 ◽  
Vol 5 (12) ◽  
pp. 3397-3402
Author(s):  
A A Simcox ◽  
C M Cheney ◽  
E P Hoffman ◽  
A Shearn

hsp40, an X-ray-induced deletion mutant of the major Drosophila melanogaster heat shock protein gene hsp70, was shown to be incorrectly regulated at the translational level. hsp40 protein synthesis persisted at a high level after the release from heat shock, whereas hsp70 protein production was rapidly repressed. This result was observed both in flies heterozygous for the hsp40 gene and in tissue culture cells transfected with the truncated gene. Analysis of the transcription of the hsp40 gene indicated that its mRNA, unlike hsp70 mRNA, was not actively destabilized after a return to control temperatures, permitting prolonged production of the mutant protein.


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