Heat shock proteins functions

Margulis, B.A., Sandler, S., Eizirik, D.L., Welsh, N., Welsh, M. (1991). Liposomal delivery of purified heat shock protein hsp70 in rat pancreatic islets as protection against interleukin I beta-induced impaired beta cell function. Diabetes 40, 1418-1422. 

Pongratz, I., Mawn, G.G., Poellinger, L. (1992). Dual roles of the 90 kD heat shock protein hsp90 in modulating functional activities of the dioxin receptor. J. Biol. Chem. 267, 13728-13734. 

Ungewickell, E. (1985). The 70-kd mammalian heat shock proteins are structurally and functionally related to the uncoating protein that releases clathrin triskelia from coated vesicles. EM BO Journal, 4, 3385-91. 

Both the heat and cold shock response are universal and have been studied extensively. The major heat shock proteins (HSPs) are highly conserved. They are involved in the homeostatic adaptation of cells to harsh environmental conditions. Some act as molecular chaperones for protein folding, while others are involved in the processing of denatured polypeptides whose accumulation would be deleterious. The cold shock results in the transient induction of cold shock proteins (CSPs), which include a family of small acidic proteins carrying the cold shock domain. The CSPs appear to be involved in various cellular functions such as transcription, translation and DNA recombination. 

Major Heat Shock Proteins and Their Function... 

Heat shock proteins (HSPs) are synthesized by cells in response to an increase in temperature, as well to various other stressful stimuli. Their main function is to ensure intracellular protein homeostasis, thus preserving the cells viability in the presence of aggression. Current evidence points to a protective role for HSPs in several aspects of critical disease, such as ischemia-reperfusion, ARDS, and multiple organ failure. The increase of a few degrees Celsius above the normal environmental temperature of cells leads to the heat shock response 1) rapid expression of heat shock genes, 2) suppression of normal protein synthesis, and 3) the ability of cells to survive a second and otherwise lethal heat challenge (thermotolerance). 

To test the irritancy potential of substances, two tests which can reliably distinguish between skin corrosives and noncorrosives are endorsed by the European Centre for the Validation of Alternative Methods (ECVAM). The testing procedures are based on the transcutaneous electrical resistance (TER) measurements of rat skin and on a human skin model. Both test systems [141-145] will be briefly outlined below. Nevertheless, these tests are not suited for the group of mild irritants which do not induce an acute effect on the barrier function. For those substances, new markers need to be evaluated. First results are available for heat shock protein 27 where higher levels were observed in skin models after exposure to mildly irritating chemicals [146, 147]. 

Moscinski L, Atadja P, Bhalla K (2004) Superior activity of the combination of histone deacetylase inhibitor LAQ824 and the FLT-3 kinase inhibitor PKC412 against human acute myelogenous leukemia cells with mutant FLT-3. Clin Cancer Res 10 4991 997 Bali P, Pranpat M, Bradner J, Balasis M, Fiskus W, Guo F, Rocha K, Kumarawsamy S, Boyapalle S, Atadja P, Seto E, Bhalla K (2005) Inhibition of histone deacetylase 6 acetylates and disrupts the chaperone function of heat shock protein 90 a novel basis for antileukemia activity of histone deacetylase inhibitors. J Biol Chem 280(29) 26729-26734 Bannister AJ, Schneider R, Kouzarides T (2002) Histone methylation Dynamic or static Cell 109 801-806... 

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