Project description:S. anginosus, S. aureus LMG 10147 and P. aeruginosa DK2 are often co-isolated in sputum samples from cystic fibrosis patients. We found that S. anginosus LMG 14502 becomes less suceptible towards treatment with several antibiotics when it's grown together with S. aureus LMG 10147 and P. aeruginosa DK2, compared to when it's grown alone. In order to elucidate the molecular mechanisms responsible, we performed RNA-seq of an S. anginosus monospecies biofilm and of a multispecies bioiflm of S. anginosus, S. aureus and P. aeruginosa. First, biofilms of S. anginosus alone or in combination with S. aureus and P. aeruginosa were grown. Next, RNA was isolated. Subsequently, a Truseq stranded RNA library preparation kit (Illumina) was used to create strand specific libraries. After a quality and concentration control, the libraries were equimolarly pooled and sequenced using an Illumina NextSeq 500, generating 75bp unpaired reads.
Project description:Production of functional proteins requires multiple steps including gene transcription and post-translational processing. MicroRNAs (miRNA) can regulate individual stages of these processes. Despite the importance of the cystic fibrosis transmembrane conductance regulator (CFTR) channel for epithelial anion transport, how its expression is regulated remains uncertain. We discovered that microRNA-138 regulates CFTR expression through its interactions with the transcriptional regulatory protein SIN3A. Treating airway epithelia with a miR-138 mimic increased CFTR mRNA and also enhanced CFTR abundance and transepithelial Cl- permeability independently of elevated mRNA levels. A miR-138 anti-miR had the opposite effects. Importantly, miR-138 altered the expression of many genes encoding proteins that associate with CFTR and may influence its biosynthesis. The most common CFTR mutation, M-NM-^TF508, causes protein misfolding, degradation, and cystic fibrosis. Remarkably, manipulating the miR-138 regulatory network also improved biosynthesis of CFTR-M-NM-^TF508 and restored Cl- transport to cystic fibrosis airway epithelia. This novel miRNA-regulated network directs gene expression from the chromosome to the cell membrane, indicating that an individual miRNA can control a cellular process broader than previously recognized. This discovery also provides new therapeutic avenues for restoring CFTR function to cells affected by the most common cystic fibrosis mutation. 12 samples of Calu-3 cells representing different interventions.
