Project description:The goals of this study were to determine differential gene expression between Achromobacter xylosoxidans clinical isolate Ax 7 in a synthetic artificial sputum media compared to a rich media control (LB).
Project description:The formation of neuronal connections requires the precise guidance of developing axons towards their targets. In the Drosophila visual system, photoreceptor neurons (R cells) project from the eye into the brain. These cells are grouped into some 750 clusters comprised of eight photoreceptors or R-cells each. R cells fall into three classes, R1-R6, R7 and R8. Posterior R8 cells are the first to project axons into the brain. How these axons select a specific pathway is not known. Here, we used a microarray-based approach to identify genes expressed in R7 and R8 neurons as they extend into the brain.
Project description:The formation of neuronal connections requires the precise guidance of developing axons towards their targets. In the Drosophila visual system, photoreceptor neurons (R cells) project from the eye into the brain. These cells are grouped into some 750 clusters comprised of eight photoreceptors or R-cells each. R cells fall into three classes, R1-R6, R7 and R8. Posterior R8 cells are the first to project axons into the brain. How these axons select a specific pathway is not known. Here, we used a microarray-based approach to identify genes expressed in R7 and R8 neurons as they extend into the brain. We used microarray analysis to measure gene expression changes when the transcription factor Runt is misexpressed in eye discs and conversely when eye discs are rendered mutant for the Senseless transcription factor.
Project description:Bacteria of the genus Achromobacter are environmental germs, with an unknown reservoir, which can become opportunistic pathogens in immunocompromised patients, and be responsible for bacteremia, meningitis, pneumonia and peritonitis. Achromobacter xylosoxidans is an emerging pathogenic bacterium frequently isolated in the context of cystic fibrosis (CF). Recent studies show that A. xylosoxidans is involved in the degradation of the respiratory function of CF patients. The respiratory ecosystem of CF patients is colonized by bacterial species that constantly fight for space and access to nutrients. In particular, these bacteria use an antagonism system, a type VI secretion nanomachine (T6SS), which represents a virulence factor in many pathogenic bacteria. This study aimed to investigate the prevalence of the T6SS genes in Achromobacter xylosoxidans isolated in cystic fibrosis patient. We also evaluated clinical and molecular characteristics of T6SS-positive A. xylosoxidans strains. We have shown that A. xylosoxidans possesses a T6SS-encoded gene cluster and that some environmental and clinical isolates assemble a functional T6SS nanomachine. The A. xylosoxidans T6SS is used to target competitor bacteria, including other CF-specific pathogens. We gathered some evidences pointing toward a role of T6SS in CF-lung colonization: i, CF mimicking conditions trigger the activation of A. xylosoxidans T6SS; ii, we detected Hcp in the sputum of CF patient and iii, the T6SS helps internalization of A. xylosoxidans in lung epithelial cells. Our study highlights a new clinical determinant of the virulence of A. xylosoxidans as well as new diagnostic and therapeutic options in cystic fibrosis.
