Amyloid beta peptide formation in cell-free preparations - Regulation by protein kinase C, calmodulin, and calcineurin
Amyloid beta peptide formation in cell-free preparations - Regulation by protein kinase C, calmodulin, and calcineurin
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DOI：
10.1074/jbc.271.40.24670
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发表时间：
1996-10-04
影响因子：
4.8
通讯作者：
Greengard, P
中科院分区：
文献类型：
--
作者：
Desdouits, F;Buxbaum, JD;Greengard, P
淀粉样β肽（A β）是一种短肽，是阿尔茨海默病中发现的淀粉样斑块和脑血管淀粉样沉积物的主要成分。缺乏无细胞系统的可用性，在其中研究A β形成限制了我们的理解的分子机制参与其生产，我们在这里报告重建这样一个无细胞系统。重组A β的形成是温度依赖性的，需要ATP。用纯化的蛋白激酶C（PKC）预孵育诱导A β形成的明显抑制，类似于在完整细胞中观察到的PKC刺激。钙调素拮抗剂W-7和三氟拉嗪抑制A β的形成，并增强PKC的作用，在无细胞系统和完整的细胞。钙/钙调蛋白激活的蛋白磷酸酶钙调磷酸酶在A β形成的调节中的作用是使用钙调磷酸酶的特异性肽抑制剂在体外以及环孢菌素A，钙调磷酸酶的细胞渗透性抑制剂，在完整细胞中证明的。我们的研究结果表明，一个单一的底物可能介导的PKC和钙调神经磷酸酶在A β形成的调节相反的行动。
Amyloid beta peptide (A beta) is a short peptide that is the major constituent of the amyloid plaques and cerebrovascular amyloid deposits found in Alzheimer's disease. The lack of availability of a cell-free system in which to study A beta formation has limited our understanding of the molecular mechanisms involved in its production, We report here the reconstitution of such a cell-free system. The reconstituted A beta formation was temperature-dependent and required ATP, Preincubation with purified protein kinase C (PKC) induced a pronounced inhibition of A beta formation, similar to that observed in intact cells upon stimulation of PKC. The calmodulin antagonists W-7 and trifluoperazine inhibited A beta formation and enhanced the action of PKC in both the cell-free system and intact cells. A role for the calcium/calmodulin-activated protein phosphatase calcineurin in the regulation of A beta formation was demonstrated using a specific peptide inhibitor of calcineurin in vitro as well as cyclosporin A, a cell-permeant inhibitor of calcineurin, in intact cells. Our results suggest that a single substrate might mediate opposing actions of PKC and calcineurin in the regulation of A beta formation.