Targeting HuR-Vav3 mRNA interaction prevents Pseudomonas aeruginosa adhesion to the cystic fibrosis airway epithelium
Mehdi Badaoui, Cyril Sobolewski, Alexandre Luscher, Marc Bacchetta, Thilo Köhler, Christian van Delden, Michelangelo Foti, Marc Chanson
Mehdi Badaoui, Cyril Sobolewski, Alexandre Luscher, Marc Bacchetta, Thilo Köhler, Christian van Delden, Michelangelo Foti, Marc Chanson
View: Text | PDF
Research Article Cell biology Infectious disease

Targeting HuR-Vav3 mRNA interaction prevents Pseudomonas aeruginosa adhesion to the cystic fibrosis airway epithelium

Abstract

Cystic fibrosis (CF) is characterized by chronic bacterial infections leading to progressive bronchiectasis and respiratory failure. Pseudomonas aeruginosa (Pa) is the predominant opportunistic pathogen infecting the CF airways. The guanine nucleotide exchange factor Vav3 plays a critical role in Pa adhesion to the CF airways by inducing luminal fibronectin deposition that favors bacteria trapping. Here we report that Vav3 overexpression in CF is caused by upregulation of the mRNA-stabilizing protein HuR. We found that HuR accumulates in the cytoplasm of CF airway epithelial cells and that it binds to and stabilizes Vav3 mRNA. Interestingly, disruption of the HuR-Vav3 mRNA interaction improved the CF epithelial integrity, inhibited the formation of the fibronectin-made bacterial docking platforms, and prevented Pa adhesion to the CF airway epithelium. These findings indicate that targeting HuR represents a promising antiadhesive approach in CF that can prevent initial stages of Pa infection in a context of emergence of multidrug-resistant pathogens.

Authors

Mehdi Badaoui, Cyril Sobolewski, Alexandre Luscher, Marc Bacchetta, Thilo Köhler, Christian van Delden, Michelangelo Foti, Marc Chanson

×

Figure 3

Enriched interaction between HuR and Vav3 transcripts in CFTR KD Calu-3 cells promotes Vav3 mRNA stability.

Options: View larger image (or click on image) Download as PowerPoint
Enriched interaction between HuR and Vav3 transcripts in CFTR KD Calu-3 ...
(A) Data showing the different AREs motifs expressed by Vav3 at the 3′UTR region. (B) The number of the predicted binding sites for RBPs recorded on Vav3 mRNA 3′UTR region. HuR, which ranked no. 1, is highlighted in orange. (C) Schematic representation of the protocol used to immunoprecipitate the mRNA bound to HuR. (D and E) Quantification of Vav3 (D) and its isoform Vav3.1 (E) expression in the pool of mRNA bound to HuR in CFTR KD cells versus CTL Calu-3 cells by qPCR after HuR RNP. Values are represented as mean ΔCt (CtCFTR KD – CtCTL) of 3 independent replicates. The IgG isotype control antibody or the omission of the immunoprecipitant antibody (NoIP) conditions served as negative controls. (F and G) Vav3 and Vav3.1 mRNA decay was analyzed by qPCR in CFTR KD versus CTL Calu-3 cells after inhibition of the de novo transcription by actinomycin-D. n = 3 in each group. Unpaired 2-tailed Student’s t test, *P < 0.05.