Mitochondrial localization and oligomeric structure of HClpP, the human homologue of E-coli ClpP
Mitochondrial localization and oligomeric structure of HClpP, the human homologue of E-coli ClpP
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DOI：
10.1006/jmbi.1999.3121
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发表时间：
1999-10-01
影响因子：
5.6
通讯作者：
Castaño, JG
中科院分区：
文献类型：
--
作者：
de Sagarra, MR;Mayo, I;Castaño, JG
使用细菌表达的重组 HClpP 蛋白（大肠杆菌 ClpP 蛋白酶的人类同源物）来获得特异性多克隆抗体。这些抗体可识别大鼠和人肝脏线粒体亚细胞部分中的 26 kDa 多肽。免疫荧光和电子显微镜研究表明，ClpP 的哺乳动物同源物位于线粒体基质中，并且倾向于与线粒体内膜相关。具有截短的 NH 末端（缺少前 58 个氨基酸残基）的 HClpP 重组蛋白在变性条件下显示出 26 kDa 的分子量。这种 N 截短的 HClpP 重组蛋白显示出 340 kDa 的天然分子量，与来自大鼠肝线粒体的部分纯化蛋白的天然分子量相同。电镜观察显示，N-截短的重组HClpP呈环形，外围有7个相同的形态单元，表现出7重对称性。天然分子量和电镜研究表明线粒体ClpP由两个具有7重对称性的七聚环组成，类似于大肠杆菌ClpP。 (C) 1999 年学术出版社。
A bacterially expressed recombinant HClpP protein, the human homologue of Escherichia coli ClpP protease, was used to obtain specific polyclonal antibodies. Those antibodies identify a 26 kDa polypeptide in mitochondrial subcellular fractions of rat and human liver. Immunofluorescence and electron microscopic studies demonstrate that the mammalian homologue of ClpP is located in the mitochondrial matrix with a tendency to be found in association with the inner mitochondrial membrane. An HClpP recombinant protein with a truncated NH, terminus (missing the first 58 amino acid residues) shows a molecular mass of 26 kDa under denaturing conditions. This N-truncated HClpP recombinant protein shows a native molecular mass of 340 kDa that is identical with the native molecular mass of the partially purified protein from rat liver mitochondria. Electron microscopy shows that the N-truncated recombinant HClpP has a ring shape with seven identical morphological units in the periphery, exhibiting a 7-fold symmetry. The native molecular mass and the electron microscopic studies suggest that mitochondrial ClpP is composed of two heptameric rings with 7-fold symmetry, similar to E, coli ClpP. (C) 1999 Academic Press.