Dataset Information

Small Noncoding Regulatory RNAs from Pseudomonas aeruginosa and Burkholderia cepacia Complex.

ABSTRACT: Cystic fibrosis (CF) is the most life-limiting autosomal recessive disorder in Caucasians. CF is characterized by abnormal viscous secretions that impair the function of several tissues, with chronic bacterial airway infections representing the major cause of early decease of these patients. Pseudomonas aeruginosa and bacteria from the Burkholderia cepacia complex (Bcc) are the leading pathogens of CF patients' airways. A wide array of virulence factors is responsible for the success of infections caused by these bacteria, which have tightly regulated responses to the host environment. Small noncoding RNAs (sRNAs) are major regulatory molecules in these bacteria. Several approaches have been developed to study P. aeruginosa sRNAs, many of which were characterized as being involved in the virulence. On the other hand, the knowledge on Bcc sRNAs remains far behind. The purpose of this review is to update the knowledge on characterized sRNAs involved in P. aeruginosa virulence, as well as to compile data so far achieved on sRNAs from the Bcc and their possible roles on bacteria virulence.

SUBMITTER: Pita T

PROVIDER: S-EPMC6321483 | biostudies-other | 2018 Nov

REPOSITORIES: biostudies-other

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Small Noncoding Regulatory RNAs from Pseudomonas aeruginosa and Burkholderia cepacia Complex.

Pita Tiago T Feliciano Joana R JR Leitão Jorge H JH

International journal of molecular sciences 20181127 12

Cystic fibrosis (CF) is the most life-limiting autosomal recessive disorder in Caucasians. CF is characterized by abnormal viscous secretions that impair the function of several tissues, with chronic bacterial airway infections representing the major cause of early decease of these patients. Pseudomonas aeruginosa and bacteria from the Burkholderia cepacia complex (Bcc) are the leading pathogens of CF patients' airways. A wide array of virulence factors is responsible for the succe ...[more]

PMID: 30486355

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Project description:Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen with distinct acute and chronic virulence phenotypes. Whereas acute virulence is typically associated with expression of a type III secretion system (T3SS), chronic virulence is characterized by biofilm formation. Many of the phenotypes associated with acute and chronic virulence are inversely regulated by RsmA and RsmF. RsmA and RsmF are both members of the CsrA family of RNA-binding proteins and regulate protein synthesis at the posttranscriptional level. RsmA activity is controlled by two small noncoding regulatory RNAs (RsmY and RsmZ). Bioinformatic analyses suggest that RsmY and RsmZ each have 3 or 4 putative RsmA binding sites. Each predicted binding site contains a GGA sequence presented in the loop portion of a stem-loop structure. RsmY and RsmZ regulate RsmA, and possibly RsmF, by sequestering these proteins from target mRNAs. In this study, we used selective 2'-hydroxyl acylation analyzed by primer extension and mutational profiling (SHAPE-MaP) chemistry to determine the secondary structures of RsmY and RsmZ and functional assays to characterize the contribution of each GGA site to RsmY/RsmZ activity. Our data indicate that RsmA has two preferential binding sites on RsmY and RsmZ, while RsmF has one preferential binding site on RsmY and two sites on RsmZ. Despite RsmF and RsmA sharing a common consensus site, RsmF binding properties are more restrictive than those of RsmA.IMPORTANCE CsrA homologs are present in many bacteria. The opportunistic pathogen Pseudomonas aeruginosa uses RsmA and RsmF to inversely regulate factors associated with acute and chronic virulence phenotypes. RsmA has an affinity for RsmY and RsmZ higher than that of RsmF. The goal of this study was to understand the differential binding properties of RsmA and RsmF by using the RsmY and RsmZ regulatory small RNAs (sRNAs) as a model. Mutagenesis of the predicted RsmA/RsmF binding sites on RsmY and RsmZ revealed similarities in the sites required to control RsmA and RsmF activity in vivo Whereas binding by RsmA was relatively tolerant of binding site mutations, RsmF was sensitive to disruption to all but two of the sites, further demonstrating that the requirements for RsmF binding activity in vivo and in vitro are more stringent than those for RsmA.

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Dataset Information

Small Noncoding Regulatory RNAs from Pseudomonas aeruginosa and Burkholderia cepacia Complex.

Publications

Small Noncoding Regulatory RNAs from <i>Pseudomonas aeruginosa</i> and <i>Burkholderia cepacia</i> Complex.

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