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Title: InvS Coordinates Expression of PrgH and FimZ and Is Required for Invasion of Epithelial Cells by Salmonella enterica serovar Typhimurium

Abstract

ABSTRACT Deep sequencing has revolutionized our understanding of the bacterial RNA world and has facilitated the identification of 280 small RNAs (sRNAs) inSalmonella. Despite the suspicions that sRNAs may play important roles inSalmonellapathogenesis, the functions of most sRNAs remain unknown. To advance our understanding of RNA biology inSalmonellavirulence, we searched for sRNAs required for bacterial invasion into nonphagocytic cells. After screening 75 sRNAs, we discovered that the ablation of InvS caused a significant decrease ofSalmonellainvasion into epithelial cells. A proteomic analysis showed that InvS modulated the levels of several type III secretedSalmonellaproteins. The level of PrgH, a type III secretion apparatus protein, was significantly lower in the absence of InvS, consistent with the known roles of PrgH in effector secretion and bacterial invasion. We discovered that InvS modulatesfimZexpression and hence flagellar gene expression and motility. We propose that InvS coordinates the increase of PrgH and decrease in FimZ that promote efficientSalmonellainvasion into nonphagocytic cells. IMPORTANCESalmonellosis continues to be the most common foodborne infection reported by the CDC in the United States. Central toSalmonellapathogenesis is the ability to invade nonphagocytic cells and to replicate inside host cells. Invasion genes are known to be regulated by protein transcriptional networks, but little ismore » known about the role played by small RNAs (sRNAs) in this process. We have identified a novel sRNA, InvS, that is involved inSalmonellainvasion. Our result will likely provide an opportunity to better understand the fundamental question of howSalmonellaregulates invasion gene expression and may inform strategies for therapeutic intervention.« less

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1368128
Report Number(s):
PNNL-SA-127078
Journal ID: ISSN 0021-9193; 49539; 453060036
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Bacteriology; Journal Volume: 199; Journal Issue: 13
Country of Publication:
United States
Language:
English
Subject:
Environmental Molecular Sciences Laboratory

Citation Formats

Wang, Lu, Cai, Xia, Wu, Shuyan, Bomjan, Rajdeep, Nakayasu, Ernesto S., Händler, Kristian, Hinton, Jay C. D., Zhou, Daoguo, and DiRita, Victor J. InvS Coordinates Expression of PrgH and FimZ and Is Required for Invasion of Epithelial Cells by Salmonella enterica serovar Typhimurium. United States: N. p., 2017. Web. doi:10.1128/JB.00824-16.
Wang, Lu, Cai, Xia, Wu, Shuyan, Bomjan, Rajdeep, Nakayasu, Ernesto S., Händler, Kristian, Hinton, Jay C. D., Zhou, Daoguo, & DiRita, Victor J. InvS Coordinates Expression of PrgH and FimZ and Is Required for Invasion of Epithelial Cells by Salmonella enterica serovar Typhimurium. United States. doi:10.1128/JB.00824-16.
Wang, Lu, Cai, Xia, Wu, Shuyan, Bomjan, Rajdeep, Nakayasu, Ernesto S., Händler, Kristian, Hinton, Jay C. D., Zhou, Daoguo, and DiRita, Victor J. Mon . "InvS Coordinates Expression of PrgH and FimZ and Is Required for Invasion of Epithelial Cells by Salmonella enterica serovar Typhimurium". United States. doi:10.1128/JB.00824-16.
@article{osti_1368128,
title = {InvS Coordinates Expression of PrgH and FimZ and Is Required for Invasion of Epithelial Cells by Salmonella enterica serovar Typhimurium},
author = {Wang, Lu and Cai, Xia and Wu, Shuyan and Bomjan, Rajdeep and Nakayasu, Ernesto S. and Händler, Kristian and Hinton, Jay C. D. and Zhou, Daoguo and DiRita, Victor J.},
abstractNote = {ABSTRACT Deep sequencing has revolutionized our understanding of the bacterial RNA world and has facilitated the identification of 280 small RNAs (sRNAs) inSalmonella. Despite the suspicions that sRNAs may play important roles inSalmonellapathogenesis, the functions of most sRNAs remain unknown. To advance our understanding of RNA biology inSalmonellavirulence, we searched for sRNAs required for bacterial invasion into nonphagocytic cells. After screening 75 sRNAs, we discovered that the ablation of InvS caused a significant decrease ofSalmonellainvasion into epithelial cells. A proteomic analysis showed that InvS modulated the levels of several type III secretedSalmonellaproteins. The level of PrgH, a type III secretion apparatus protein, was significantly lower in the absence of InvS, consistent with the known roles of PrgH in effector secretion and bacterial invasion. We discovered that InvS modulatesfimZexpression and hence flagellar gene expression and motility. We propose that InvS coordinates the increase of PrgH and decrease in FimZ that promote efficientSalmonellainvasion into nonphagocytic cells. IMPORTANCESalmonellosis continues to be the most common foodborne infection reported by the CDC in the United States. Central toSalmonellapathogenesis is the ability to invade nonphagocytic cells and to replicate inside host cells. Invasion genes are known to be regulated by protein transcriptional networks, but little is known about the role played by small RNAs (sRNAs) in this process. We have identified a novel sRNA, InvS, that is involved inSalmonellainvasion. Our result will likely provide an opportunity to better understand the fundamental question of howSalmonellaregulates invasion gene expression and may inform strategies for therapeutic intervention.},
doi = {10.1128/JB.00824-16},
journal = {Journal of Bacteriology},
number = 13,
volume = 199,
place = {United States},
year = {Mon Apr 24 00:00:00 EDT 2017},
month = {Mon Apr 24 00:00:00 EDT 2017}
}
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