Isolation of Possibly Significant Chromosomal Contributors to Cadmium Resistance in Selected Drosophila melanogaster
Authors:Ellie Altomare, Austin Nguyen, Gregory Zacharias
Mentor:Catharine McElwain, Professor, Loyola Marymount University
The fruit fly, Drosophila melanogaster, demonstrates sensitivity to heavy metal exposure that is both variable and selectable. Our lab has demonstrated significant differences in survival of wild-type D. melanogaster raised on varied concentrations of Cadmium-enriched food. Preliminary data from flies across fourteen generations of exposure indicate selectable resistance to cadmium and decline in fly body cadmium levels, quantified by mass spectrometry. This decrease in cadmium content may indicate a metabolic mechanism of resistance, rather than the literature-suggested sequestration mechanism. Through a series of crosses with chromosomally marked stocks, this lab is isolating chromosomes from the resistant line to test for significant contributions to resistance. Further experiments may be conducted if a single significant chromosomal contributor is found. The ability of flies to develop resistance to heavy metals may have significant impact on food webs in contaminated environments and may also indicate levels of exposure to higher trophic levels. This comes to particular interest in light of restoring the local Ballona wetlands, which are contaminated with heavy metals.