State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, People's Republic of China.
PLoS One. 2011;6(9):e25484. doi: 10.1371/journal.pone.0025484. Epub 2011 Sep 26.
Yersinia pestis is the causative agent of plague. The two transcriptional regulators, PhoP and RovA, are required for the virulence of Y. pestis through the regulation of various virulence-associated loci. They are the global regulators controlling two distinct large complexes of cellular pathways.
METHODOLOGY/PRINCIPAL FINDINGS: Based on the LacZ fusion, primer extension, gel mobility shift, and DNase I footprinting assays, RovA is shown to recognize both of the two promoters of its gene in Y. pestis. The autoregulation of RovA appears to be a conserved mechanism shared by Y. pestis and its closely related progenitor, Y. pseudotuberculosis. In Y. pestis, the PhoP regulator responds to low magnesium signals and then negatively controls only one of the two promoters of rovA through PhoP-promoter DNA association.
CONCLUSIONS/SIGNIFICANCE: RovA is a direct transcriptional activator for its own gene in Y. pestis, while PhoP recognizes the promoter region of rovA to repress its transcription. The direct regulatory association between PhoP and RovA bridges the PhoP and RovA regulons in Y. pestis.
鼠疫耶尔森氏菌是鼠疫的病原体。PhoP 和 RovA 这两个转录调控因子通过调节各种毒力相关基因座，对鼠疫耶尔森氏菌的毒力是必需的。它们是控制两个截然不同的细胞途径的大型复杂全球调节因子。
方法/主要发现：基于 LacZ 融合、引物延伸、凝胶迁移率变动分析和 DNase I 足迹分析，发现 RovA 在鼠疫耶尔森氏菌中识别其基因的两个启动子。RovA 的自身调控似乎是鼠疫耶尔森氏菌及其密切相关的前体，假结核耶尔森氏菌所共有的保守机制。在鼠疫耶尔森氏菌中，PhoP 调节剂对低镁信号作出反应，然后通过 PhoP-启动子 DNA 结合仅负调控 rovA 的两个启动子之一。
结论/意义：RovA 是鼠疫耶尔森氏菌自身基因的直接转录激活剂，而 PhoP 则识别 rovA 的启动子区域以抑制其转录。PhoP 和 RovA 之间的直接调节关联在鼠疫耶尔森氏菌中连接了 PhoP 和 RovA 调节子。
