title: Biomarker discovery and transcriptomic responses in Daphnia magna exposed to munitions constituents.
abstract: Ecotoxicogenomic approaches are emerging as alternative methods in environmental monitoring because they allow insight into pollutant modes of action and help assess the causal agents and potential toxicity beyond the traditional end points of death, growth, and reproduction. Gene expression analysis has shown particular promise for identifying gene expression biomarkers of chemical exposure that can be further used to monitor specific chemical exposures in the environment. We focused on the development of gene expression markers to detect and discriminate between chemical exposures. Using a custom cDNA microarray for Daphnia magna, we identified distinct expression fingerprints in response to exposure at sublethal concentrations of Cu, Zn, Pb, and munitions constituents. Using the results obtained from microarray analysis, we chose a suite of potential biomarkers for each of the specific exposures. The selected potential biomarkers were tested in independent chemical exposures for specificity using quantitative reverse transcription polymerase chain reaction. Six genes were confirmed as differentially regulated bythe selected chemical exposures. Furthermore, each exposure was identified by response of a unique combination (suite) of individual gene expression biomarkers. These results demonstrate the potential for discovery and validation of novel biomarkers of chemical exposures using gene expression analysis, which could have broad applicability in environmental monitoring.
authors: Department of Chemistry, Jackson State University, Jackson, Mississippi 39217, USA.
authors: Natalia
authors: N
authors: Garcia-Reyero
authors: Helen C
authors: HC
authors: Poynton
authors: Alan J
authors: AJ
authors: Kennedy
authors: Xin
authors: X
authors: Guan
authors: B Lynn
authors: BL
authors: Escalon
authors: Bonnie
authors: B
authors: Chang
authors: Julia
authors: J
authors: Varshavsky
authors: Alex V
authors: AV
authors: Loguinov
authors: Chris D
authors: CD
authors: Vulpe
authors: Edward J
authors: EJ
authors: Perkins
mesh_terms: D000818:Animals; D015415:Biomarkers; D003621:Daphnia / Q000187:drug effects* / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D008670:Metals / Q000633:toxicity*; D020411:Oligonucleotide Array Sequence Analysis; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity; D054041:Weapons
chemical_list: D015415:Biomarkers; D008670:Metals; D014874:Water Pollutants, Chemical