Differential gene expression profiles in embryos of the lizard Podarcis sicula under in ovo exposure to cadmium.
Screening for differentially expressed genes is a straightforward approach to study the molecular basis of contaminant toxicity. In this paper, the mRNA differential display technique was applied to analyze transcriptional regulation in response to cadmium exposure in the lizard embryos. Lizard eggs may be particularly susceptible to soil contamination and in ovo exposure may interfere or disrupt normal physiological function in the developing embryo, including regulation of gene expression. Fertilized eggs of the lizard Podarcis sicula were incubated in cadmium-contaminated soil at 25 degrees C for 20 days. Gene expression profiling showed 5 down- and 9 up-regulated genes. Four cDNAs had no homology to known gene sequences, thus suggesting that may either encode not yet identified proteins, or correspond to untranslated regions of mRNA molecules. Four fragments exhibited significant sequence similarity with genes encoding novel proteins or ESTs derived from other vertebrates. The remaining genes are mainly involved in molecular pathways associated with processes such as membrane trafficking, signal transduction, cytoskeletal organization, cell proliferation and differentiation. Cadmium also affected the expression of factors actively involved in the regulation of the transcription machinery. Down-regulated genes are mainly associated with cellular metabolism and cell-cycle regulation and apoptosis. All of these differentially expressed genes may represent candidates that function in cadmium responses. The present study leads to an increased understanding of genes and/or the biochemical pathways involved in perturbation of embryo development following cadmium exposure.
Trinchella
Francesca
F
Department of Biological Sciences, University Federico II, Via Mezzocannone 8, Naples, Italy.
Cannetiello
Marcello
M
Simoniello
Palma
P
Filosa
Silvana
S
Scudiero
Rosaria
R
D000818:Animals; D015152:Blotting, Northern; D019256:Cadmium Chloride / Q000633:toxicity*; D020869:Gene Expression Profiling / Q000379:methods; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D053263:Gene Regulatory Networks; D008116:Lizards / Q000196:embryology / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012989:Soil Pollutants / Q000633:toxicity*; D013997:Time Factors; D015053:Zygote / Q000378:metabolism
D012333:RNA, Messenger; D012989:Soil Pollutants; D019256:Cadmium Chloride