Polynucleotide Phosphorylase Regulates Multiple Virulence Factors and the Stabilities of Small RNAs RsmY/Z in Pseudomonas aeruginosa.
Polynucleotide Phosphorylase Regulates Multiple Virulence Factors and the Stabilities of Small RNAs RsmY/Z in Pseudomonas aeruginosa.
复制标题
多核苷酸磷酸化酶调节铜绿假单胞菌中的多种毒力因子和小RNA RsmY/Z 的稳定性
DOI：
10.3389/fmicb.2016.00247
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发表时间：
2016
影响因子：
5.2
通讯作者：
Wu W
中科院分区：
文献类型：
--
作者：
Chen R;Weng Y;Zhu F;Jin Y;Liu C;Pan X;Xia B;Cheng Z;Jin S;Wu W
转录后调控使细菌能够迅速对环境压力作出反应。多核苷酸磷酸化酶（PNPase）具有n端催化核心和c端RNA结合KH-S1结构域，参与RNA加工。在这里，我们证明了铜绿假单胞菌的PNPase的KH-S1结构域是III型分泌系统（T3SS）和细菌毒力所必需的。转录组分析显示PNPase在基因调控中具有多效性。特别是，ΔKH-S1突变体中exsA的RNA水平降低，这是导致T3SS表达减少的原因。同时，ΔKH-S1突变体菌毛生物合成基因下调，VI型分泌系统（T6SS）基因上调，这是由于小rna、RsmY、RsmZ水平升高所致。进一步研究发现，KH-S1结构域的缺失不影响RsmY/Z的转录，但增加了其稳定性。体内拉下和体外电泳迁移率转移试验（EMSA）表明RsmY/Z与KH-S1片段之间存在直接相互作用。总之，本研究揭示了PNPase在铜绿假单胞菌毒力因子调控和小rna稳定性中的作用。
Post-transcriptional regulation enables bacteria to quickly response to environmental stresses. Polynucleotide phosphorylase (PNPase), which contains an N-terminal catalytic core and C-terminal RNA binding KH-S1 domains, is involved in RNA processing. Here we demonstrate that in Pseudomonas aeruginosa the KH-S1 domains of PNPase are required for the type III secretion system (T3SS) and bacterial virulence. Transcriptome analysis revealed a pleiotropic role of PNPase in gene regulation. Particularly, the RNA level of exsA was decreased in the ΔKH-S1 mutant, which was responsible for the reduced T3SS expression. Meanwhile, the pilus biosynthesis genes were down regulated and the type VI secretion system (T6SS) genes were up regulated in the ΔKH-S1 mutant, which were caused by increased levels of small RNAs, RsmY, and RsmZ. Further studies revealed that deletion of the KH-S1 domains did not affect the transcription of RsmY/Z, but increased their stabilities. An in vivo pull-down and in vitro electrophoretic mobility shift assay (EMSA) demonstrated a direct interaction between RsmY/Z and the KH-S1 fragment. Overall, this study reveals the roles of PNPase in the regulation of virulence factors and stabilities of small RNAs in P. aeruginosa.