Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009443 (cold)
 92,137 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using homologous molecular probes, we examined the influence of equivalent temperature shifts on the in vivo expression of genes coding for a constitutive heat shock protein (Hsc70), heat shock proteins (Hsps) (Hsp70 and Hsp90), and polyubiquitin, after acclimation in the American lobster, Homarus americanus. We acclimated sibling, intermolt, juvenile male lobsters to thermal regimes experienced during overwintering conditions (0.4 +/- 0.3 degrees C), and to ambient Pacific Ocean temperatures (13.6 +/- 1.2 degrees C), for 4-5 weeks. Both groups were subjected to an acute thermal stress of 13.0 degrees C, a temperature shift previously found to elicit a robust heat shock response in ambient-acclimated lobsters. Animals were examined after several durations of acute heat shock (0.25-2 hours) and after several recovery periods (2-48 hours) at the previous acclimation temperature, following a 2-hour heat shock. Significant inductions in Hsp70, Hsp90, and polyubiquitin messenger RNA (mRNA) levels were found for the ambient-acclimated group. Alternatively, for the cold-acclimated group, an acute thermal stress over an equivalent interval resulted in no induction in mRNA levels for any of the genes examined. For the ambient-acclimated group, measurements of polyubiquitin mRNA levels showed that hepatopancreas, a digestive tissue, incurred greater irreversible protein damage relative to the abdominal muscle, a tissue possessing superior stability over the thermal intervals tested.
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PMID:Thermal acclimation and stress in the American lobster, Homarus americanus: equivalent temperature shifts elicit unique gene expression patterns for molecular chaperones and polyubiquitin. 1189 92

Trichinella-type larvae (L(1)) are found in the muscles of infected wild animals and domestic pigs and are the cause of trichinosis in man and other animals throughout the world. These parasites are exposed to low temperatures during their life cycle. On this premise, three Trichinella species of different types of habitat (the arctic T. nativa, the cosmopolitan T. spiralis, and the tropical T. nelsoni) were selected to examine the effect of a shift in temperature, from 37 to 4 degrees C, on long-term survival. Evaluation was then made of whether these effects were related to differential protein synthesis and/or heat shock protein (Hsp) expression. Test samples at 0, 2, 4, or 8 h and 1, 5, or 9 days after the temperature shift were obtained and subjected to Hsp determination by Western blotting. Total protein changes were explored by SDS-PAGE followed by densitometric analysis of the gels. During the "acclimatization phase" (at 2, 4, and 8 h), a different total protein and a depressed Hsp expression pattern were shown in each Trichinella species. Following acclimatization, Hsp70, but not Hsp60 or Hsp90, markedly increased above control levels in the three species, indicating a role for this Hsp as a classic stress protein. The synthesis of a 50-kDa Hsp was significantly induced in T. spiralis larvae, suggesting its potential function as a cold shock protein in this species.
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PMID:Stress response to cold in Trichinella species. 1200 26

The anti-heat shock protein (Hsp)-90 monoclonal antibody AC-16 reacts on blots with Hsp90 and a 50 kDa protein (prot-50) from infective-stage (L1) larvae of the nematode Trichinella spiralis. We examined Hsp90 and prot-50 levels by densitometric analysis of immunoblots of T. spiralis larval extracts prepared before (time 0, 37 degrees C) and after oxidative [hydrogen peroxide (H2O2)] stress, or cold shock at 4 degrees C. Extracts from H2O2-exposed L1 were obtained after 2 h; the others at 2, 4, and 8 h after the temperature shift. After H2O2 shock, the constitutive Hsp90 and prot-50 were both significantly induced and appeared as slower migrating inducible isoforms. However, whereas Hsp90 levels decreased after cold shock, prot-50 levels immediately and persistently increased after shock at 4 degrees C. These data present compelling evidence that the prot-50 described here functions as a Hsp and a cold shock protein.
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PMID:Oxidative and cold shock cause enhanced induction of a 50 kDa stress protein in Trichinella spiralis. 1204 59

The heterotrimeric G proteins, G(12) and G(13), are closely related in their sequences, signaling partners, and cellular effects such as oncogenic transformation and cytoskeletal reorganization. Yet G(12) and G(13) can act through different pathways, bind different proteins, and show opposing actions on some effectors. We investigated the compartmentalization of G(12) and G(13) at the membrane because other G proteins reside in lipid rafts, membrane microdomains enriched in cholesterol and sphingolipids. Lipid rafts were isolated after cold, nonionic detergent extraction of cells and gradient centrifugation. Galpha(12) was in the lipid raft fractions, whereas Galpha(13) was not associated with lipid rafts. Mutation of Cys-11 on Galpha(12), which prevents its palmitoylation, partially shifted Galpha(12) from the lipid rafts. Geldanamycin treatment, which specifically inhibits Hsp90, caused a partial loss of wild-type Galpha(12) and a complete loss of the Cys-11 mutant from the lipid rafts and the appearance of a higher molecular weight form of Galpha(12) in the soluble fractions. These results indicate that acylation and Hsp90 interactions localized Galpha(12) to lipid rafts. Hsp90 may act as both a scaffold and chaperone to maintain a functional Galpha(12) only in discrete membrane domains and thereby explain some of the nonoverlapping functions of G(12) and G(13) and control of these potent cell regulators.
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PMID:Hsp90 interactions and acylation target the G protein Galpha 12 but not Galpha 13 to lipid rafts. 1211 99

Aquatic ectotherms can adapt to a wide range of temperature changes, but the molecular mechanisms that underlie this adaptability are not well understood. We identified genes that are differentially expressed in the catfish ( Ictalurus punctatus) brain using a cDNA microarray approach to gain an initial understanding of adaptation to low temperature. Among 660 genes analyzed, 61 were differentially expressed when compared at 12 degrees C and 24 degrees C. Gene induction was rapid, occurring within 2 h of the temperature shift. The major categories of differentially expressed genes included (1) genes for chaperones such as Hsp70 and Hsp70/Hsp90 organizing protein; (2) genes for transcription factors and gene products involved in signal transduction pathways such as zinc-finger proteins, calmodulin kinase inhibitor, the nuclear autoantigen SG2NA, interferon regulatory factor 3, and inorganic pyrophosphatase; (3) genes involved in lipid metabolism such as TB2 and acyl CoA binding protein; and (4) genes involved in the translational machinery such as ribosomal proteins. Some genes were induced transiently, whereas others were induced in an enduring fashion. Several genes, primarily ribosomal protein genes, were down regulated, indicating reduced metabolic activities after extended incubation at the low temperature. Thus channel catfish respond to low temperature by adjusting expression of a large number of genes. The rapid induction of proteins involved in signal transductions and chaperones suggests that both de novo synthesis of cold-induced proteins and modification of existing proteins are required for adaptation and tolerance of catfish to low environmental temperature.
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PMID:Differential gene expression in the brain of channel catfish ( Ictalurus punctatus) in response to cold acclimation. 1224 3

Heat shock proteins (Hsps) are a ubiquitous component of the cellular response to stress in both prokaryotic and eukaryotic organisms, but their role and function during desiccation stress in terrestrial arthropods has received limited attention. Molecular responses to rehydration are arguably as important as those to desiccation in maintaining cellular integrity and enzyme activity, but the role of Hsps during stress recovery is poorly understood and has never been addressed with respect to rehydration in insects. This study identifies distinct differences in the Hsp response to desiccation and rehydration in the flesh fly Sarcophaga crassipalpis, as well as differences in the desiccation responses of diapausing and nondiapausing pupae. In nondiapausing pupae, the expression of two inducible Hsps (Hsp23 and Hsp70) is upregulated by desiccation, but the water loss threshold for Hsp expression changes at different rates of dehydration. Continued desiccation results in the prolonged expression of both Hsp23 and Hsp70, which may contribute to the delayed adult eclosion noted in samples desiccated for more than 3 days at <5% relative humidity/25 degrees C. In diapausing pupae, hsp23 and hsp70 transcripts are already highly expressed and are not further upregulated by desiccation stress. Both of the constitutive Hsps investigated, Hsp90 and Hsc70, were unresponsive to desiccation in both nondiapausing and diapausing pupae. However, both Hsp90 and Hsc70 were upregulated upon rehydration in nondiapausing and diapausing pupae. These results indicate distinct roles for the different Hsps during desiccation stress and rehydration/stress recovery. The response to desiccation recovery (rehydration) is similar to the Hsp response to cold recovery identified in S. crassipalpis: Hsp90 and Hsc70 are upregulated in both cases.
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PMID:Desiccation and rehydration elicit distinct heat shock protein transcript responses in flesh fly pupae. 1476 55

Phosphatidic acid (PA) is emerging as an important lipid signalling molecule. In plants, it is implicated in various stress-signalling pathways and is formed in response to wounding, osmotic stress, cold stress, pathogen elicitors, Nod factors, ethylene and abscisic acid. How PA exerts its effects is still unknown, mainly because of the lack of characterized PA targets. In an approach to isolate such targets we have used PA-affinity chromatography. Several PA-binding proteins were present in the soluble fraction of tomato and Arabidopsis cells. Using mass spectrometric analysis, several of these proteins, including Hsp90, 14-3-3 proteins, an SnRK2 serine/threonine protein kinase and the PP2A regulatory subunit RCN1 could be identified. As an example, the binding of one major PA-binding protein, phosphoenolpyruvate carboxylase (PEPC), was characterized further. Competition experiments with different phospholipids confirmed specificity for PA. Hypo-osmotic treatment of the cells increased the amount of PEPC that bound the PA beads without increasing the absolute amount of PEPC. This suggests that PEPC's affinity for PA had increased. The work shows that PA-affinity chromatography/mass spectrometry is an effective way to isolate and identify PA-binding proteins from plants.
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PMID:Isolation and identification of phosphatidic acid targets from plants. 1527 72

The migratory locust Locusta migratoria L., which is widely distributed throughout the world, exhibits within- and between-population variation in cold tolerance. To understand physiological adaptation in populations, we studied the genetic basis of thermotolerance in Hainan (tropical) and Liaoning (temperate) populations and measured expression of Hsp70 and Hsp90 mRNA in both populations at low (0 degrees C) and high temperatures (40 degrees C). Phenotypic variation of thermotolerance is heritable. Heritable characteristics differed among different stages of locust egg development, as well as among different measures of thermotolerance. Nuclear genetic factors, rather than cytoplasmic factors, contribute to differences in cold tolerance between the tropical and temperate populations of the migratory locust; for heat tolerance, maternal effects were involved in three stages of egg development. Expression of Hsp90 mRNA was induced in temperate population after heat shock (40 degrees C x 12h), whereas expression of Hsp70 and 90 was induced in tropical population after cold shock (0 degrees C x 12h). We suggest that thermotolerance of locust eggs has a complex genetic basis and heat shock proteins may be involved in differences of thermotolerance between locust populations.
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PMID:Differences in egg thermotolerance between tropical and temperate populations of the migratory locust Locusta migratoria (Orthoptera: Acridiidae). 1616 5

The full-length Hsp90 cDNA in Delia antiqua was cloned and sequenced. The deduced polypeptide comprised 717 amino acid residues, with a molecular mass of 82 140 Da. Summer- and winter-diapauses both elevated HSP90 transcript levels in D. antiqua pupae. Levels gradually increased with time in summer diapausing pupae whereas levels fluctuated in winter diapausing pupae. Cold- and heat-stressing summer- and winter-diapausing individuals further elevated HSP90 expression. mRNA levels gradually increased with time in summer diapausing pupae whereas levels decreased with time after an initial increase in winter diapausing pupae. HSP90 expression was also up-regulated following cold- and heat-stresses in non-diapausing pupae. Heat-stress gradually increased the mRNA level with time whereas cold-stress gradually decreased levels after an initial increase. These results suggest that the development and physiology of summer- and winter-diapauses, as monitored via variation in HSP90 transcript levels, can be substantial different.
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PMID:The expression of the HSP90 gene in response to winter and summer diapauses and thermal-stress in the onion maggot, Delia antiqua. 1631 70

Over the past decade, mouse models of cancer have come to resemble human disease much more closely than simple subcutaneous or orthotopic systems. Intervention strategies that work on these new model systems are more likely to have an impact clinically. We have shown recently that antiangiogenic stress imposed by loss of Id protein in endothelial progenitor cells results in dramatic central necrosis in breast tumors initiated in mice by overexpression of the her2/neu oncogene. Tumor cells remain viable at the periphery, perhaps via the hypoxic response pathway which allows the lesions to expand. Inhibition of this pathway by the inactivation of the Hif-1alpha chaperone Hsp90 in combination with antiangiogenic stress leads to the first reported complete regression of these aggressive breast tumors.
Cold Spring Harb Symp Quant Biol 2005
PMID:Induction of complete regressions of oncogene-induced breast tumors in mice. 1686 74


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