Project description:A Chinese herbal formula, Gengnianchun, ameliorates β-amyloid peptide toxicity in a Caenorhabditis elegans model of Alzheimer’s disease
Project description:Infection of Pseudomonas donghuensis HYS strain and its fur deletion mutant in Caenorhabditis elegans was conducted to assess changes in the expression profile of Caenorhabditis elegans, and potential core virulence factors were identified by measuring the gene expression levels of the HYS colonizing the nematode's intestine. Preliminary studies indicate that P. donghuensis HYS exhibits significant toxicity towards Caenorhabditis elegans, yet the underlying mechanisms of this pronounced toxicity remain unclear. Previous work identified several virulence factors contributing to the toxicity of HYS through detection and functional validation; however, the molecular mechanisms responsible for its strong toxicity have not been elucidated. Therefore, we aim to analyze the mechanisms underlying HYS's pronounced toxicity by examining the responses of infected Caenorhabditis elegans. The Ferric uptake regulator (Fur) is responsible for maintaining iron homeostasis in Gram-negative bacteria, and given that HYS possesses a greater iron uptake capacity than other common species in the same genus, such as Pseudomonas aeruginosa, we hypothesize that Fur may play a critical role in the strong toxicity exhibited by HYS. Consequently, we infected Caenorhabditis elegans with both HYS and its fur deletion mutant and analyzed the changes in the expression profile of Caenorhabditis elegans. We observed a significant reduction in toxicity following the deletion of fur, indicating that Fur regulates core virulence factors. To identify these core virulence factors, we conducted transcriptomic sequencing of the pathogenic bacteria under various conditions and performed a screening for virulence factors.
Project description:Effective toxicological testing of the vast number of new and existing chemicals currently in use will require efficient and cost effective methods. We evaluated the utility of a simple, low cost toxicity testing system employing the nematode Caenorhabditis elegans to identify toxicologically relevant changes in gene expression. Dichlorvos and fenamiphos, which are organophosphorous pesticides that inhibit acetylcholinesterase were chosen as model toxicants to test the usefulness of the C. elegans toxicity testing system, and mefloquine, which appears to perturb neuronal Ca++ homeostasis, provided an out-group for analysis. Keywords: gene expression array-based (RNA / in situ oligonucleotide)
Project description:Although non-coplanar PCBs are ubiquitous organic chemicals known to induce numerous biological responses and thus are toxic to man and wildlife, little is known about the toxic mode of action. Using PCB52, an ortho-substituted, 2,2’,5,5’-tetrachlorobiphenyl, it was possible to pinpoint the relationship between induced gene expression and observed toxicity in the model nematode Caenorhabditis elegans. Keywords: stress response
Project description:The potential environmental risk of single-walled carbon nanotubes (SWCNTs) is evaluated using Caenorhabditis elegans (C. elegans) as an ecotoxicological animal model. Highly soluble amide-modified SWCNTs (a-SWCNTs) are used in the present study so that the dose-response impact of SWCNTs could be studied. mechanisms. a-SWCNTs are efficiently taken up by worms during feeding and cause significant toxicity in worms, including retarded growth, shortened lifespan and defective embryogenesis. Genome-wide gene expression analysis is performed to investigate the toxic molecular