MecA, an adaptor protein necessary for ClpC chaperone activity
MecA, an adaptor protein necessary for ClpC chaperone activity
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DOI：
10.1073/pnas.0535717100
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发表时间：
2003-03-04
影响因子：
11.1
通讯作者：
Turgay, K
中科院分区：
文献类型：
--
作者：
Schlothauer, T;Mogk, A;Turgay, K
枯草芽孢杆菌的ClpC是atp依赖性的HSP100/Clp蛋白，参与一般的应激生存。ClpC与蛋白酶ClpP和接头蛋白MecA的复合体也通过调节转录因子ComK的蛋白水解来控制能力的发展。我们研究了ClpC的体外伴侣活性，发现MecA的存在对ClpC的主要伴侣活性至关重要。特别是，MecA使ClpC能够溶解和重新折叠聚集的蛋白质。最后，在ClpP存在的情况下，MecA允许clpc依赖性的未折叠或热聚集蛋白降解。这项研究表明，像MecA这样的接头蛋白通过与其同源的ClpC蛋白相互作用，可以在蛋白质质量控制网络中发挥双重作用，通过挽救或与ClpP一起降解聚集的蛋白质。因此，MecA可以协调底物靶向与ClpC激活，为HSP100/Clp蛋白活性的调节增加了另一层。
ClpC of Bacillus subtilis is an ATP-dependent HSP100/Clp protein involved in general stress survival. A complex of ClpC with the protease ClpP and the adaptor protein MecA also controls competence development by regulated proteolysis of the transcription factor ComK. We investigated the in vitro chaperone activity of ClpC and found that the presence of MecA was crucial for the major chaperone activities of ClpC. In particular, MecA enabled ClpC to solubilize and refold aggregated proteins. Finally, in the presence of ClpP, MecA allowed the ClpC-dependent degradation of unfolded or heat-aggregated proteins. This study demonstrates that adaptor proteins like MecA through interaction with their cognate ClpC proteins can have a dual role in the protein quality-control network by rescuing, or together with ClpP, by degrading, aggregated proteins. MecA can thereby coordinate substrate targeting with ClpC activation, adding another layer to the regulation of HSP100/Clp protein activity.