Lagido, C., Flett, A., Pettitt, J. and Glover, L.A. We are interested in how a whole organism responds to environmental stress at a genetic level. To address this question, we have made a brightly luminescent strain of C. elegans carrying the American firefly luc gene, fused to gfp under the control of the sur-5 promoter. Luciferase catalyses the oxidation of the exogenous luciferin substrate and generates light by an ATP-dependent reaction. We exploit bioluminescence as a sensitive indicator of health following exposure to stress. Our aim is to develop an efficient assay to carry out a genome-wide screen for genes involved in the response of C. elegans to unfavourable environmental conditions.. Here we show that 19h exposure to sub-lethal levels of a heavy metal results in reduced light emission in a concentration dependent manner. This response correlates well with slower feeding, as assessed by the optical density of the bacterial suspensions on which the worms were cultured. We also tested the impact of the metal on development and reproduction after approximately 3 days exposure. Metal concentrations that affect development and reproduction in longer exposures correlate well with those that give rise to changes in luminescence in the19 h assays.. Ongoing work is aimed at testing the link between light output and cellular ATP at the whole organism level. The in vitro ATP content of metal exposed N2 worms decreases with increasing metal concentrations, as previously observed by luminescence. We are at present investigating how the drop in ATP levels relates to changes in biomass. In addition, we are investigating the stability of expression of luciferase in our strain under standard metal exposure conditions, by measuring GFP fluorescence. Finally, we will discuss the use of our strain as a physiological and metabolic reporter in combination with genome-wide RNAi to investigate the involvement of particular genes in the stress response. Our approach is also of significance in other research areas such metabolic research, ageing, interactions with microbial pathogens, etc.
|Publication status||Published - 2006|
|Event||European Worm Meeting (2006) - Hersonissos, Greece|
Duration: 29 Apr 2006 → 3 May 2006
|Conference||European Worm Meeting (2006)|
|Period||29/04/06 → 3/05/06|