You are here:
The Genomic Basis for Evolved Pollution Tolerance in Killifish (Fundulus heterclitus).
Citation:
Triant, D. A., D. E. NACCI, D. M. CHAMPLIN, AND A. Whitehead. The Genomic Basis for Evolved Pollution Tolerance in Killifish (Fundulus heterclitus). Presented at SETAC North America 30th Annual Meeting, New Orleans, LA, November 19 - 23, 2009.
Impact/Purpose:
The purpose of this research is to describe methods and reveal genes associated with ecologically valuable traits using an environmentally important model species.
Description:
Uncovering the molecular mechanisms of adaptive variation is a leading challenge in evolutionary biology. Identifying genes that influence ecological traits can provide insight into the evolutionary processes behind genomic responses to environmental change. Here, we examine the genomic basis for evolved tolerance to dioxin-like chemical pollutants in killifish (Fundulus heteroclitus), using complementary functional and structural approaches. Killifish populations from non-polluted sites are relatively sensitive to these toxicants in comparison to other fish species. However, profound chemical tolerance has evolved independently within a short period of time in isolated killifish populations living in several highly toxic sites along the Atlantic coast. We conducted controlled dose-response experiments on 1st and 2nd generation progeny from tolerant and sensitive wild populations to identify genes and gene expression patterns associated with pollution tolerance. Following exposure and phenotyping, high-quality RNA was extracted from individual embryos and hybridized to 7,500 gene oligonucleotide microarrays. Initially, comparisons among doses, populations, and generations are being used to identify genes and gene expression patterns associated with pollution tolerance at a single site. Comparisons will be extended to other pollution tolerant populations, including one where quantitative trait locus (QTL) mapping is in progress. Results from this research will help address whether similar mechanisms and similar genomic changes underlie evolved pollution tolerance in multiple independently-derived populations.