QTL AnalysiS and EXPERIMENTAL EVOLUTION
The first step in biofilm formation is adherence to a surface. We are investigating the genetic basis of plastic adherence in natural isolates, as well as through de novo evolution. Inspired by research conducted in bacteria, we are using growth in the presence of plastic beads to select for the ability to adhere to plastic. We will then comparing the genetic basis of the newly evolved ability to that existing in strains isolated from the environment.
Yeast are grown while attaching to plastic beads (sample bead shown on the left). Photo above shows the surface of a bead with red glowing cells attached.
We have evolved populations of yeast from multiple different genetic backgrounds for over 600 generations and are now uncovering the mutations responsible for the increase in adherence ability.
The figure on the right shows the increase in adherence ability over time in 6 populations from one genetic background; dashed lines are sexual populations, while solid are asexual. The figure on the right shows the frequency of mutations over time in one of the populations.
NIH R15: The Evolution and Genetics of a Complex Fungal Virulence Trait (Role: PI)