Modification in gene expression pattern as biomarkers of pesticide exposure in native reptile species

PARACHÚ MARCÓ MA. VIRGINIA; SIROSKI, PABLO A.; ODETTI, LUCÍA; DENSLOW, NANCY; POLETTA, GISELA L.; LÓPEZ GONZÁLEZ, EVELYN

Asunción del Paraguay

Congreso; XI Congreso Latinoamericano de Mutagénesis, Carcinogénesis y Teratogénesis Ambiental. I Jornada de la Sociedad Paraguaya De Genétic; 2019

ALAMCTA

Habitat loss and fragmentation produced by agricultural expansion, as well as pesticides exposure and its mixtures become a great concern for many reptile species in South America. During the last decade, through different studies we demonstrated the effect produced by pesticides on genotoxicity, oxidative stress, immunotoxicity, enzymatic and developmental alterations in embryos, yearlings and adults of native reptile species. The tremendous progress obtained in the last years in the field of molecular biology and bioinformatics enables the development of a new family of biomarkers, based in the analysis of the transcription of genes related to cellular stress that can be used to detect the exposure to xenobiotics, acting as early warning sensors. The aim of this new research line is to identify gene molecular markers and relate their expression levels to other conventional toxicological assays already validated and applied as routine markers by our research group, in order to improve our understanding of the molecular processes underlying pesticide toxicological effects. Up to the moment, these kinds of biomarkers have not been studied in any crocodilian species worldwide. We carried out studies on the expression level of antioxidant enzyme genes in caimans subchronically exposed to pesticide formulations and its mixtures, demonstrating its alteration even when enzymatic activity was not modified. We also conducted a transcriptomic study through RNAseq (Illumina) in juveniles exposed to pesticide formulations, identifying gene groups and functional pathways affected by these compounds in blood cells. These new data allow us to identify new genes sensible to xenobiotic exposure that can be applied in future studies and contribute to the protection of natural populations of wild species environmentally exposed.