Biochemical and Spatial Coincidence in the Provisional Ser/Thr Protein Kinase Interaction Network of Mycobacterium tuberculosis
Biochemical and Spatial Coincidence in the Provisional Ser/Thr Protein Kinase Interaction Network of Mycobacterium tuberculosis
复制标题
DOI：
10.1074/jbc.m114.559054
复制
发表时间：
2014-07-25
影响因子：
4.8
通讯作者：
Sassetti, Christopher M.
中科院分区：
文献类型：
--
作者：
Baer, Christina E.;Iavarone, Anthony T.;Sassetti, Christopher M.
许多革兰氏阳性菌通过丝氨酸/苏氨酸蛋白激酶（STPKs）信号转导来协调细胞过程，但这些磷酸化信号级联的结构尚不清楚。为了研究原核STPK系统的网络结构，我们全面探索了结核分枝杆菌Ser/Thr激酶组的信号转导模式。自磷酸化是STPK激活的主要方式，但11 M.结核STPK在体外也显示出有效的交叉磷酸化的特定模式。每个激酶结构域固有的生化特异性被用来映射临时信号网络，揭示了一个三层架构，包括主调节器，信号转导和终端底物。荧光显微镜显示STPKs特异性地定位于细胞中。主STPK集中在与其底物相同的亚细胞位点，为生化定义的网络提供额外的支持。总之，这些研究暗示了M的分支功能结构。结核病Ser/Thr激酶组，可以使水平信号传播。这种系统水平的方法为理解M.结核病，这从根本上不同于以前定义的线性组氨酸激酶级联。
Many Gram-positive bacteria coordinate cellular processes by signaling through Ser/Thr protein kinases (STPKs), but the architecture of these phosphosignaling cascades is unknown. To investigate the network structure of a prokaryotic STPK system, we comprehensively explored the pattern of signal transduction in the Mycobacterium tuberculosis Ser/Thr kinome. Autophosphorylation is the dominant mode of STPK activation, but the 11 M. tuberculosis STPKs also show a specific pattern of efficient cross-phosphorylation in vitro. The biochemical specificity intrinsic to each kinase domain was used to map the provisional signaling network, revealing a three-layer architecture that includes master regulators, signal transducers, and terminal substrates. Fluorescence microscopy revealed that the STPKs are specifically localized in the cell. Master STPKs are concentrated at the same subcellular sites as their substrates, providing additional support for the biochemically defined network. Together, these studies imply a branched functional architecture of the M. tuberculosis Ser/Thr kinome that could enable horizontal signal spreading. This systems-level approach provides a biochemical and spatial framework for understanding Ser/Thr phospho-signaling in M. tuberculosis, which differs fundamentally from previously defined linear histidine kinase cascades.