Heat shock

Heat shock

In biochemistry, heat shock is the effect of subjecting a cell to a higher temperature than that of the ideal body temperature of the organism from which the cell line was derived.

Heat shock proteins (HSPs) are a part of the cell's internal repair mechanism. They are also called stress-proteins. They respond to heat, cold and oxygen deprivation by activating several cascade pathways. Heat shock proteins are also present in cells under perfectly normal conditions. They act like ‘chaperones,’ making sure that the cell’s proteins are in the right shape and in the right place at the right time. For example, HSPs help new or distorted proteins fold into shape, which is essential for their function. They also shuttle proteins from one compartment to another inside the cell, and transport old proteins to ‘garbage disposals’ inside the cell. Heat shock proteins are also believed to play a role in the presentation of pieces of proteins (or peptides) on the cell surface to help the immune system recognize diseased cells.

In fish that survive at 0°C, heat shock can be induced with temperatures as low as 5°C, whereas thermophilic bacteria that proliferate at 50°C will not express heat shock proteins until temperatures reach approximately 60°C [http://arjournals.annualreviews.org/doi/pdf/10.1146/annurev.ge.22..?cookieSet=1] . The process of heat shocking can be done in a CO2 incubator, O2 incubator, or a hot water bath.

Induction of heat shock is a method by which genes can be introduced into cells via a vector. This is done by mixing the vector with competent bacteria in a microcentrifuge tube. First, the tube is cooled to a low temperature for several minutes, usually with an ice bath. The tube is then quickly moved into warm water, preferably around 40°C. This sudden change in temperature causes the pores to open up to larger sizes, allowing DNA molecules to enter. After a brief interval, the tube is quickly cooled to a low temperature again. This closes up the pores, and traps the DNA inside. With this, the cells would have been transformed. However, it must be noted that, as with almost all transformation techniques, this method is far from 100% efficient.


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  • heat shock — heat shock. См. тепловой шок. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • heat shock — šiluminis smūgis statusas T sritis fizika atitikmenys: angl. heat shock; thermal shock vok. Wärmestoß, m rus. тепловой удар, m; термический удар, m pranc. choc thermique, m …   Fizikos terminų žodynas

  • Heat shock protein — Heat shock proteins (HSP) are a group of proteins whose expression is increased when the cells are exposed to elevated temperatures or other stress. This increase in expression is transcriptionally regulated. This dramatic upregulation of the… …   Wikipedia

  • Heat shock protein 47 — Heat shock protein 47, also known as SERPINH1 is a serpin which serves as a human chaperone protein for collagen.cite web | title = Entrez Gene: SERPINH1 serpin peptidase inhibitor, clade H (heat shock protein 47), member 1, (collagen binding… …   Wikipedia

  • heat shock protein — n any of a group of proteins that were orig. isolated from certain bacteria exposed to heat, that occur esp. in cells subjected to heat stress, that keep the proteins in the cell from unraveling, and that are either identical with or comprise a… …   Medical dictionary

  • heat-shock proteins — heat shock proteins. См. белки теплового шока. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Heat shock factor — Pfam box Name = HSF type DNA binding Symbol = HSF DNA bind width = 300px caption = Structure of the dimeric DNA binding domain of the yeast heat shock factor (cyan and green) bound to DNA (brown) based on PDB|3HTS. Pfam= PF00447 InterPro=… …   Wikipedia

  • Heat Shock Protein — Hitzeschockproteine (engl. Heat Shock Protein, HSP) sind Proteine, die anderen Proteinen bei der Faltung oder bei der Erhaltung ihrer Sekundärstruktur unter Extrembedingungen helfen. Sie werden in erhöhtem Maße gebildet, nachdem Zellen Hitze oder …   Deutsch Wikipedia

  • Heat shock protein 70 (Hsp70) internal ribosome entry site (IRES) — The heat shock protein 70 (Hsp70) internal ribosome entry site (IRES) is an RNA element that allows cap independent translation during conditions such as heat shock and stress. It has been shown that the 216 nucleotide long 5 UTR contains… …   Wikipedia

  • Heat shock protein — Protéine de choc thermique Les protéines de choc thermique ou HSP (pour Heat Shock Proteins), sont une classe de protéines chaperonnes initialement découvertes en raison de leur inductibilité par la chaleur. Leur rôle, crucial pour toutes les… …   Wikipédia en Français

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