Activation of protein kinase B (Akt/RAC-protein kinase) by cellular stress and its association with heat shock protein Hsp27
Activation of protein kinase B (Akt/RAC-protein kinase) by cellular stress and its association with heat shock protein Hsp27
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DOI：
10.1016/s0014-5793(97)00541-3
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发表时间：
1997-06-30
期刊：
影响因子：
3.5
通讯作者：
Kikkawa, U
中科院分区：
文献类型：
--
作者：
Konishi, H;Matsuzaki, H;Kikkawa, U
蛋白激酶 B（PKB，也称为 Akt 或 RAC 蛋白激酶）由热休克和高渗处理等细胞应激激活，通过测量转染 COS-7 细胞免疫沉淀酶的活性，发现氧化应激以及 CdCl2 和 NaAsO2 化学应激源激活蛋白激酶 B（PKB，也称为 Akt 或 RAC 蛋白激酶）。应激处理后，30-kDa 磷蛋白与来自用[P-32]正磷酸盐代谢标记的细胞的 PKB 进行免疫共沉淀，通过免疫印迹分析和免疫共沉淀，该磷蛋白被鉴定为 Hsp27，一种小的热休克蛋白。Hsp27 的关联对 PKB 具有特异性，因为热休克蛋白不与其他蛋白激酶（如蛋白激酶 C 和蛋白激酶 C）共免疫沉淀。 PKN，当细胞用H2O2处理时，PKB逐渐被激活，Hsp27与PKB的结合同时增强，PKB活性增强。在热休克细胞中，处理后立即检测到PKB的激活和Hsp27的结合，当细胞进一步在37℃培养时，热休克蛋白的结合减少，而PKB保持刺激的活性，这些结果表明Hsp27在信号中参与了PKB的激活过程。各种应激的传导途径。 (C) 1997 年欧洲生化学会联合会。
Protein kinase B (PKB, also named as Akt or RAC-protein kinase), that is activated by cellular stress such as heat shock and hyperosmotic treatment, was revealed to be activated by oxidative stress and by chemical stressors of CdCl2 and NaAsO2 by measuring the activity of the enzyme immunoprecipitated from the transfected COS-7 cells. Upon stress treatment, a 30-kDa phosphoprotein was co-immunoprecipitated with PKB from the cells metabolic labeled with [P-32]orthophosphate, The phosphoprotein was identified as Hsp27, a small heat shock protein, by immunoblot analysis and co-immunoprecipitation, The association of Hsp27 was specific to PKB as the heat shock protein was not co-immunoprecipitated with other protein kinases such as protein kinase C and PKN, When the cells were treated with H2O2, PKB was activated gradually and the association of Hsp27 with PKB increased concurrently with the enhancement of PKB activity, In heat-shocked cells, activation of PKB and the association of Hsp27 were detected immediately after the treatment, and the association of the heat shock protein decreased while PKB kept stimulated activity when the cells were further incubated at 37 degrees C, These results suggest that Hsp27 is involved in the activation process of PKB in the signal transduction pathway of various forms of stress. (C) 1997 Federation of European Biochemical Societies.