title: Polynucleotide Phosphorylase Regulates Multiple Virulence Factors and the Stabilities of Small RNAs RsmY/Z in Pseudomonas aeruginosa.
abstract: 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.
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Ronghao
authors.initials: R
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Yuding
authors.initials: Y
authors.lastname: Weng
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Chang
authors.initials: C
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Xia
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai UniversityTianjin, China; Department of Molecular Genetics and Microbiology, College of Medicine, University of FloridaGainesville, FL, USA.
authors.forename: Shouguang
authors.initials: S
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University Tianjin, China.
authors.forename: Weihui
authors.initials: W
authors.lastname: Wu
keywords: P. aeruginosa; PNPase; gene regulation; pathogenesis; small RNA