Investigating how physiologies & genomes evolve

Dr. Katherine O'Brien







Research interests

I am broadly interested in studying how organisms adapt to environmental challenges. The evolution of phenotypic plasticity is a possible adaptive outcome from environmental heterogeneity. Despite the widespread occurrence of phenotypic plasticity, the genetic architecture and specific molecular variants that underlie plasticity remain largely unknown. My current work in the Montooth lab is focused on a fine scale investigation of the alcohol metabolism pathway and how changes in regulation within this gene network affect phenotypic plasticity.

Drosophila melanogaster has adapted to utilize a variety of fermented food sources, requiring efficient metabolism of ethanol and acetic acid. The matching of enzyme activities within the ethanol and acetic acid catabolic pathway confers a high tolerance by reducing toxic intermediates. My project explores the role of epistasis and gene networks in adaptation to novel environments by asking the following questions.

(1) Does the genome respond differently to multiple simultaneous selective pressures? (2) If so, are these responses to two different environmental factors additive or non-additive? (3) How do these processes differ between larvae and adults?

To address these questions, I am working on identifying and characterizing novel genes responsible for maintaining fitness within alcohol stressed environments to better understand alcohol tolerance across life stages. This work provides useful insight into the link between metabolism, gene expression and the resulting phenotype.