Article

Hfq and Hfq-dependent small RNAs are major contributors to multicellular development in Salmonella enterica serovar Typhimurium.

Department of Microbiology; Tumor and Cell Biology (MTC); Karolinska Institutet, Stockholm, Sweden; Department of Microbiology; Tumor and Cell Biology (MTC); Karolinska Institutet, Stockholm, Sweden; Current Affiliation: INEB-Instituto de Engenharia Biomédica; Universidade do Porto; Porto, Portugal.
RNA biology (impact factor: 5.56). 04/2012; 9(4):489-502. DOI:10.4161/rna.19682 pp.489-502
Source: PubMed

ABSTRACT The RNA chaperone Hfq and its associated small RNAs (sRNAs) regulate a variety of phenotypes in bacteria. In this work, we show that Hfq is a master regulator of biofilm formation in Salmonella enterica serovar Typhimurium. Hfq and two Hfq-dependent sRNAs (ArcZ and SdsR) are required for rdar morphotype expression in S. typhimurium. Hfq controls rdar biofilm formation through the major biofilm regulator CsgD. While csgD mRNA steady-state levels are altered in a sdsR mutant, ArcZ seems to work mainly at the post-transcriptional level. Overexpression of ArcZ complemented rdar morphotype formation of an hfq mutant under plate-grown conditions. Although ArcZ activates rpoS expression, its effect on csgD expression is mainly independent of RpoS. ArcZ does not only regulate rdar morphotype expression, but also the transition between sessility and motility and the timing of type 1 fimbriae vs. curli fimbriae surface-attachment at ambient temperature. Consequently, ArcZ is a major regulator of rdar biofilm development.

0 0
 · 
0 Bookmarks
 · 
20 Views
  • Source
    Article: sRNAs and the virulence of Salmonella enterica serovar Typhimurium.
    Magali Hébrard, Carsten Kröger, Shabarinath Srikumar, Aoife Colgan, Kristian Händler, Jay C D Hinton
    [show abstract] [hide abstract]
    ABSTRACT: The combination of genomics and high-throughput cDNA sequencing technologies has facilitated the identification of many small RNAs (sRNAs) that play a central role in the post-transcriptional gene regulation of Salmonella enterica serovar Typhimurium. To date, most of the functionally characterized sRNAs have been involved in the regulation of processes which are not directly linked to virulence. Just five sRNAs have been found to affect the ability of Salmonella to replicate within mammalian cells, but the precise regulatory mechanisms that are used by sRNAs to control Salmonella pathogenicity at the post-transcriptional level remain to be identified. It is anticipated that an improved understanding of sRNA biology will shed new light on the virulence of Salmonella.
    RNA biology 04/2012; 9(4):437-45. · 5.56 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

ArcZ activates rpoS expression
 
ArcZ complemented rdar morphotype formation
 
associated small RNAs
 
biofilm formation
 
csgD expression
 
csgD mRNA steady-state levels
 
curli fimbriae surface-attachment
 
Hfq controls rdar biofilm formation
 
Hfq-dependent sRNAs
 
major biofilm regulator CsgD
 
major regulator
 
master regulator
 
phenotypes
 
post-transcriptional level
 
rdar biofilm development
 
rdar morphotype expression
 
RNA chaperone Hfq
 
S. typhimurium
 
Salmonella enterica serovar Typhimurium
 
type 1 fimbriae