Project description:Exposure to cadmium is associated with a variety of human diseases. At low concentrations, cadmium activates the transcription of stress-responsive genes, which can prevent or repair the adverse effects caused by this metal. Using C. elegans, 290 genes were identified that are differentially expressed (≥1.5-fold) following a 4 or 24 hour exposure to cadmium. Several of these genes are known to be involved in metal detoxification, including mtl-1, mtl-2, cdr-1 and ttm-1, confirming the efficacy of the study. The majority, however, were not previously associated with metal-responsiveness and are novel. Gene Ontology analysis mapped these genes to cellular/ion trafficking, metabolic enzymes and proteolysis categories. RNAi-mediated inhibition of 50 cadmium-responsive genes resulted in an increased sensitivity to cadmium toxicity, demonstrating that these genes are involved in the resistance to cadmium toxicity. Several functional protein interacting networks were identified by interactome analysis. Within one network, the signaling protein KEL-8 was identified. Kel-8 protects C. elegans from cadmium toxicity in a mek-1 (MAPKK)-dependent manner. Because many C. elegans genes and signal transduction pathways are evolutionarily conserved, these results may contribute to the understanding of the functional roles of various genes in cadmium toxicity in higher organisms. Keywords: gene expression time course
Project description:Cadmium is toxic and intricate pathways linked to metallothioneins (MT) drive the detoxification process. Whist the mechanisms are well understood in mammalian systems, detailed knowledge is still elusive in invertebrates (which notably differ to mammalian systems). The model nematode Caenorhabditis elegans is ideally suited for assessing metallothionein mediates detoxification in invertebrates as is relatively short-lived, can be easily exposed and its genome is fully sequenced and widely annotated. The aim of the experiment was to identify new MT mediated target genes involved in Cd toxicosis.
Project description:Cadmium is toxic and intricate pathways linked to metallothioneins (MT) drive the detoxification process. Whist the mechanisms are well understood in mammalian systems, detailed knowledge is still elusive in invertebrates (which notably differ to mammalian systems). The model nematode Caenorhabditis elegans is ideally suited for assessing metallothionein mediates detoxification in invertebrates as is relatively short-lived, can be easily exposed and its genome is fully sequenced and widely annotated. The aim of the experiment was to identify new MT mediated target genes involved in Cd toxicosis. The global transcriptome was compared in wild type and a MT double knockout strain raised in the presence or absence of 30 µM Cd.
