Induced hsp70 is in small, cytoplasmic complexes in a cell culture model of renal ischemia: a comparative study with heat shock.
Cell Stress Chaperones
; 5(4): 314-27, 2000 Oct.
Article
en En
| MEDLINE
| ID: mdl-11048654
ABSTRACT
A number of clinical conditions are known to result in the induction of heat shock proteins, but detailed studies on stress response have focused mostly on heat shock as a model. We have analyzed the induction and intracellular distribution of heat shock proteins in a reversible adenosine triphosphate (ATP) depletion model of renal ischemia. Two Hsp70 homologues, Hsp70 in the cytoplasm and BiP in the endoplasmic reticulum (ER) lumen, were found significantly induced during the recovery phase of ATP depletion. Other members of the heat shock protein family, such as Hsp90, constitutive Hsc70, and a related protein Hop60, were not induced. The induction of stress proteins on ATP depletion differed from that after heat shock in the kinds of proteins elaborated, their induction kinetics, and their intracellular distributions. Biochemical fractionation and indirect immunofluorescence experiments indicated that Hsp70 was predominantly cytoplasmic in the recovery phase of ischemia-like stress. Velocity sedimentation on sucrose gradients showed that induced Hsp70 sedimented as small, soluble complexes, ranging in size from 4S20,w to 8S20,w. The results suggest a role for induced Hsp70 that may be different from one of protecting aggregated proteins as under heat shock and emphasize the need for their characterization in other clinical conditions that result in stress response.
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1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas HSP70 de Choque Térmico
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Respuesta al Choque Térmico
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Citoplasma
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Isquemia
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Riñón
Límite:
Animals
Idioma:
En
Revista:
Cell Stress Chaperones
Año:
2000
Tipo del documento:
Article