Larissa Williams – Aquatic Toxicology

Genome-wide evolutionary analysis of toxicant resistance in natural populations and elucidation of molecular mechanisms of toxicant response and resistance

Larissa Williams

Dr. Larissa Williams

Williams Lab Website

Professor Williams’ research is broadly focused on understanding the molecular mechanisms involved in the response to toxicant exposure in aquatic organisms and the role of genetic variation in adaptation to toxicant exposure.  In the field, Professor Williams is interested in documenting patterns of genetic variation in estuarine species, comparing populations from clean and contaminated environments, to understand how the abiotic environment shapes levels of genetic diversity, structure, migration and genetic drift.  In addition to estuarine sites, Bates College’s proximity to a contaminated river, the Androscoggin, provides a unique opportunity to study changes in genetic variation of resident organisms due to toxicant exposure in a freshwater ecosystem.  Studies comparing estuarine and freshwater ecosystems will offer unique insight into the similarities and differences in molecular and evolutionary responses to heterogeneous contaminant profiles across organisms and ecosystem types.  In the lab, Dr. Williams is interested in using the powerful zebrafish model to determine the importance of transcription factors in the NF-E2 family in the embryonic response to environmental toxicant exposure. Because embryos are at increased risk from effects of toxicant exposure, it is important to understand the role of these transcription factors in both the pathogenesis of these effects as well as adaptive changes in gene expression that help to protect the embryo from toxicity.

Selected Publications

Williams LM, Oleksiak MF (2011). Evolutionary and Functional analyses of Cytochrome P4501A    promoter polymorphisms in natural populations. Molecular Ecology, 20(24):5236-47

Williams LM, Oleksiak MF (2011). Selectively important SNPs identified in natural populations. Molecular Biology and Evolution, 28(6):1817-26.

Williams LM, Oleksiak MF (2008). Signatures of selection in natural populations adapted to chronic pollution. BMC Evolutionary Biology, 8:282.