Heat shock proteins molecular chaperone role

Welch, W.J. (1991). The role of heat shock proteins as molecular chaperones Curr. Opin. Cell Biol. 3, 1033-1038. 

Many of the chaperones double as heat shock-proteins (Hsp). When a cell is put under stress that can cause proteins to denature, such as too high a temperature, it produces heat-shock proteins. Their names are abbreviated to Hsp plus their subunit molecular mass in kDa. Hsp70, for example, is a ubiquitous heat-shock protein in eukaryotes. It is known in E. coli as DnaK for historical reasons because it was first discovered from a supposed role in DNA replication. Hsp70 is also important in protein trafficking and the conveying of proteins across membranes, because the denatured state is important in these processes. In protein biosynthesis, the unfolded state of the nascent polypeptide chain is passed on to DnaK, which maintains it in an extended form. The chain, under the influence of ATP and co-chaperones such as DnaJ and GrpE, is handed over to GroEL. 

Georgopolous, C., and Welch, W. 1993. Role of major heat shock proteins as molecular chaperones. Annu. Rev. Cell Biol. 9 601-635. 

Exposure of cells to stress, such as heat shock or oxidative stress, results in the accumulation of molecular chaperones, commonly known as heat shock proteins (Hsps). Hsp90 has emerged over the last few years as being of particular interest because of its role in the evolution, development, and disease pathology of cancer. Novel piperazinyl, morpholino, and piperidyl derivatives 883 of the Hsp90 inhibitor CCT018159 <2005BML3338> and... 

Heat shock proteins (HSPs) are a family of proteins expressed in almost all organisms from prokaryotes to humans. HSPs were originally described about four decades ago as proteins that were induced in the Drosophila melanogaster in response to a heat stress and hence derive the name HSR However, research over the years has uncovered these proteins to have a multitude of functions. Primarily, all HSPs act as molecular chaperons and assist in proper folding of naive proteins. Furthermore, HSPs have important roles in cellular processes including cell survival, inflammation, immunity, ion channel repair, and others. HSPs are also induced by a variety of stressors. Reactive oxygen species, cytotoxic injury, necrosis, ultraviolet radiation, metals, and many others are some examples. 

Ubiquitin, found in several cellular compartments (e.g., cytoplasm and the nucleus), belongs to a class of proteins referred to as stress proteins. Stress proteins, also called heat shock proteins (hsp), are so named because their syntheses are accelerated (and in some cases initiated) when cells encounter stress. (The name heat shock protein is misleading, because a variety of stressful conditions besides elevated temperature induce their synthesis.) Other stress proteins act as molecular chaperones, that is, they promote protein folding (p. 692). Heat shock proteins and molecular chaperones also play significant roles in protein transport and intermolecular interactions. 

Wang, W., B. Vinocur, O. Shoseyov, and A. Altman. 2004. Role of plant heat-shock proteins and molecular chaperones in the abiotic stress response. Trends Plant Sci. 9 244-252. 

Heat shock proteins (HSPs) are members of a family of molecular chaperones playing critical roles in protein folding, intracellular trafficking of proteins, and coping with proteins... 

Molecular chaperones are proteins that have been said to play a role in the maintenance of conformation, stability, and function of the client protein within the cell. Heat-shock protein 90 (Hsp 90) is an ATP-dependent molecular chaperone that has several oncogenic client proteins involved in signal transduction, cell cycle regulation, and apoptosis, and has recently become a focus of interest as potential anticancer drug target. 

Hubbard TJP, Sander C. The role of heat-shock and chaperone proteins in protein folding Possible molecular mechanisms. Protein Engineering 1991 4 711-7. 

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