Engineered chemotaxis core signaling units indicate a constrained kinase-off state.
Engineered chemotaxis core signaling units indicate a constrained kinase-off state.
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DOI：
10.1126/scisignal.abc1328
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发表时间：
2020-11-10
影响因子：
7.3
通讯作者：
Crane BR
中科院分区：
文献类型：
--
作者：
Muok AR;Chua TK;Srivastava M;Yang W;Maschmann Z;Borbat PP;Chong J;Zhang S;Freed JH;Briegel A;Crane BR
细菌化学感受器、组氨酸激酶 CheA 和偶联蛋白 CheW 形成具有卓越传感特性的跨膜分子阵列。受体分别根据引诱剂或驱避剂的存在来抑制或刺激 CheA 激酶活性。我们对化学感受器细胞质区域进行了改造，使其呈现受体三聚体-二聚体构型，与 CheA 和 CheW 形成明确的复合物，并促进 CheA 激酶关闭状态。这些核心信号单元的模拟物被组装成同质的，并通过脉冲偶极电子自旋共振光谱 (PDS)、小角度 X 射线散射、靶向蛋白质交联和冷冻电子显微镜进行定点自旋标记来研究。激酶关闭状态特别稳定，具有相对较低的结构域迁移率，并将组氨酸底物和对接结构域与激酶核心相关联，从而阻止催化活性。总之，这些数据为核心信号单元的抑制状态提供了一个实验限制模型，并表明化学感受器间接隔离激酶和底物结构域以限制组氨酸自磷酸化。
Bacterial chemoreceptors, the histidine kinase CheA, and the coupling protein CheW form transmembrane molecular arrays with remarkable sensing properties. The receptors inhibit or stimulate CheA kinase activity depending on the presence of attractants or repellants, respectively. We engineered chemoreceptor cytoplasmic regions to assume a trimer-of-receptor-dimers configuration that formed well-defined complexes with CheA and CheW and promoted a CheA kinase-off state. These mimics of core signaling units were assembled to homogeneity and investigated by site-directed spin-labeling with pulse-dipolar electron-spin resonance spectroscopy (PDS), small-angle x-ray scattering, targeted protein cross-linking, and cryo-electron microscopy. The kinase-off state was especially stable, had relatively low domain mobility, and associated the histidine substrate and docking domains with the kinase core, thus preventing catalytic activity. Together, the data provide an experimentally restrained model for the inhibited state of the core signaling unit and suggest that chemoreceptors indirectly sequester the kinase and substrate domains to limit histidine autophosphorylation.
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影响因子：
3.6
作者：
Briegel A;Ames P;Gumbart JC;Oikonomou CM;Parkinson JS;Jensen GJ
通讯作者：
Jensen GJ
影响因子：
2.9
作者：
Haglin ER;Yang W;Briegel A;Thompson LK
通讯作者：
Thompson LK
影响因子：
9.8
作者：
Airola MV;Sukomon N;Samanta D;Borbat PP;Freed JH;Watts KJ;Crane BR
通讯作者：
Crane BR
域间连接子在细菌趋化组氨酸激酶 CheA 中的调节作用
影响因子：
3.2
作者：
Ding, Xueye;He, Qiang;Wang, Xiqing
通讯作者：
Wang, Xiqing
影响因子：
64.5
作者：
Bilwes, AM;Alex, LA;Simon, MI
通讯作者：
Simon, MI