E-GEOD-48943 - Gene expression profiles of Hyalella azteca populations with different pyrethroid sensitivities
Released on 17 July 2013, last updated on 3 June 2014
The goal of the study was to investigate gene expression differences in Hyalella azteca exposed to pyrethroid insecticides and compare a laboratory strain to a wild population believed to be resistant to the pesticides. H. azteca reared in the laboratory at the University of CA, Berkeley (UCB) were exposed to cyfluthrin, a commerical pyrethroid insecticide for 96-h. A wild population collected from Grayson Creek (GC), CA was reared in the laboratory for several days and also exposed to cyfluthrin. Toxicity testing revealed that GC animals were two orders of magnitude less sensitive to cyfluthrin compared to the laboratory animals with the no observed effect concentration (NOEC) for UCB = 0.4 ng/L and GC= 170 ng/L. Unexposed, control animals and animals exposed to 0.4 ng/L (GC and UCB) or 170 ng/L cyfluthrin were collected following 96-h treatments. Differences in gene expression were measured using a custom Hyalella azteca microarray. Gene expression profiles revealed that laboratory H. azteca responded to cyfluthrin through differential expression of genes involved in neurological system processes. In contract, H. azteca from Grayson Creek showed a pattern of oxidative stress through the differential expression of glutathione-S-transferases, heat shock proteins, and other genes involved in oxidation-reduction processes. Four replicate exposures consisting of ten animals were collected for each treatment or control. A one-color hybridization protocol was used so that each sample was labeled with cy3 and only one sample was hybridized to each array.
transcription profiling by array
Helen C Poynton <email@example.com>, Bonnie J Blalock, Don Weston, John Colbourne, Maria Sepulveda