A large-scale mutational analysis of two-component signaling systems of lonsdalea quercina revealed that KdpD-KdpE regulates bacterial virulence against host poplar trees
A large-scale mutational analysis of two-component signaling systems of lonsdalea quercina revealed that KdpD-KdpE regulates bacterial virulence against host poplar trees
复制标题
对槲寄生双组分信号系统的大规模突变分析表明，KdpD-KdpE 调节细菌对宿主杨树的毒力
DOI：
10.1094/mpmi-10-17-0248-r
复制
发表时间：
2018
影响因子：
3.5
通讯作者：
Qian W.
中科院分区：
文献类型：
--
作者：
Yang R.-L.;Deng C.-Y.;Wei J.-W.;He W.;Li A.-N.;Qian W.
白杨是分布于北方的植物群落中的优势种，也是林业研究中常用的模式植物。白杨的生产可受到细菌感染的抑制，包括Lonsdalea quercinasubsp.populi，它是一种革兰氏阴性细菌，可引起树皮溃疡病。然而，发病机制的分子基础仍然没有得到表征。在这项研究中，我们注释了由L. quercinasubsp.populiN-5-1基因组，并确定了18个假定的组氨酸激酶和24个反应调节因子。大规模的突变分析表明，19 TCS基因调控细菌对白杨的毒力。此外，kdpE的缺失或kdpD的过表达导致细菌毒力几乎完全丧失。我们观察到kdpE和kdpD形成一个双顺反子操纵子。KdpD具有自激酶活性，可与KdpE结合（Kd= 5.73 ± 0.64 μM）。此外，KdpE是OmpR家族反应调节剂。染色质免疫沉淀测序分析显示，KdpE结合到44个基因启动子内的不完全回文序列，包括应激反应基因Lqp 0434、Lqp 3037和Lqp 3270。对TCS功能的综合分析有助于揭示白杨溃疡病的发病规律。
Poplar, which is a dominant species in plant communities distributed in the northern hemisphere, is commonly used as a model plant in forestry studies. Poplar production can be inhibited by infections caused by bacteria, includingLonsdalea quercinasubsp.populi, which is a gram-negative bacterium responsible for bark canker disease. However, the molecular basis of the pathogenesis remains uncharacterized. In this study, we annotated the two-component signal transduction systems (TCSs) encoded by theL. quercinasubsp.populiN-5-1 genome and identified 18 putative histidine kinases and 24 response regulators. A large-scale mutational analysis revealed that 19 TCS genes regulated bacterial virulence against poplar trees. Additionally, the deletion ofkdpEor overexpression ofkdpDresulted in almost complete loss of bacterial virulence. We observed thatkdpEandkdpDformed a bi-cistronic operon. KdpD exhibited autokinase activity and could bind to KdpE (Kd= 5.73 ± 0.64 μM). Furthermore, KdpE is an OmpR family response regulator. A chromatin immunoprecipitation sequencing analysis revealed that KdpE binds to an imperfect palindromic sequence within the promoters of 44 genes, including stress response genesLqp0434,Lqp3037, andLqp3270. A comprehensive analysis of TCS functions may help to characterize the regulation of poplar bark canker disease.