The basic driving forces of evolution, mutation and selection, are often difficult to observe and study in the laboratory because it requires large numbers of individuals and long time periods in order to observe the evolutionary changes.
During our research we found that the yeast knockout collection (~4200 strains each containing a deletion of a non-essential gene) is a treasure trove for evolutionary and cell biological studies. Genome sequencing of several of these mutant strains in my lab identified additional mutations in each mutant that help the strain cope with the initial gene deletion.
Undergraduate students in SRI biology labs.
These suppressor mutations most likely arose during the copying of the original knockout collection, during which strains with suppressor mutations had the opportunity to outcompete the original mutant strain. Knowledge of the suppressor mutations can give insights not only into evolutionary mechanisms but also into the interactions between different cell biological pathways (systems biology).
The goal of the project is to systematically analyze the genomes of yeast deletion strains propose a mechanism of phenotypic suppression and test the model. Furthermore, we will perform evolutionary experiments in the lab to identify the factors that are responsible for the rapid genetic adaptation of yeast.