Project description:microRNAs fine-tune the regulation of numerous biological processes by mediating gene expression post-transcriptionally. Mature miRNAs associate with argonaute (AGO) proteins to form the RNA-induced silencing complex (RISC) that binds to and blocks translation of target mRNAs. In our study, we address the function of miRNAs in regulating DNA damage responses in-vivo, by exploiting the nematode model organism Caenorhabditis elegans. Using next-generation sequencing, we obtained miRNA expression profiles of WT worms as well as mutants harboring a loss-of-function deletion of the C. elegans AGO gene alg-2 that display abnormal cell death in response to genotoxic stress. 2.5 hours after exposure to ionizing irradiation, the miRNA transcriptomes of both WT and alg-2(ok304) mutant worms were only mildly altered in comparison to their respective untreated controls. However, irrespective of treatment, alg-2(ok304) mutants exhibited noticeable dysregulation of several miRNA families with known physiological functions. Reduced levels of some of these miRNAs might explain the abnormal DNA damage response of alg-2-deficient C. elegans.
Project description:Young adult fer-15;fem-1 Caenorhabditis elegans were infected with Staphylococcus aureus for 8 h to determine the transcriptional host response to Staphylococcus aureus. Analysis of differential gene expression in C. elegans young adults exposed to two different bacteria: E. coli strain OP50 (control), wild-type Staphylococcus aureus RN6390. Samples were analyzed at 8 hours after exposure to the different bacteria. These studies identified C. elegans genes induced by pathogen infection. Keywords: response to pathogen infection, innate immunity, host-pathogen interactions
Project description:To understand how microRNAs are involved in stress response, we examined their expression changes in C. elegans animals that were exposed to stress conditions, including heat shock, oxidation, hypoxia and starvation.
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
