NSF Postdoctoral Fellowship in Biology FY 2019: The evolution of gene expression in Sccharomyces cerevisiae experimental evolution

Phillips Mark A, Irvine CA

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2019, Broadening Participation of Groups Under-represented in Biology. The fellowship supports a research and training plan for the Fellow that will increase the participation of groups underrepresented in biology. Understanding the genetics that determine how organisms adapt to a changing environment is a challenging problem in evolutionary biology, but essential for predicting future evolutionary change. The Fellow will use laboratory evolution experiments to determine the long-term evolutionary response of yeast populations, reproducing in different ways, when exposed to environmental stressors. To increase participation from members of underrepresented groups in biology, the Fellow will conduct workshops in collaboration with the Louis Stokes Alliance for Minority Participation (LSAMP) at Oregon State University to train undergraduates from such groups in computational methods common in biological data science. Findings from laboratory evolution experiments suggest a fundamental difference in the genetics of adaptation between populations of organisms that reproduce by mitosis or budding versus those that involve meiosis. Adaptation in the former is fueled by de novo beneficial mutation, while standing genetic variation drives the process in the latter. Experimental study systems involving meiosis are required to model evolutionary change in higher eukaryotic organisms using this mode of reproduction. However, experiments that feature such systems are limited by scale; carrying out powerful experiments is difficult with complex eukaryotes. Thus, there is a need for large, highly-replicated experiments that feature reproduction involving meiosis. In addition, despite strong evidence that changes in gene regulation drive adaptation to selective pressures, laboratory evolution experiments rarely feature gene expression assays. The Fellow seeks to address these gaps with evolution experiments employing Saccharomyces cerevisiae to address the following questions: (1) How repeatable is the evolutionary response across a range of selective pressures? (2) How do patterns of gene expression change across different stages of adaptation? And (3) What are the relative contributions of changes in cis and trans regulation in driving adaptation? The Fellow will recruit students from OSU's LSAMP program to contribute to this research endeavor as a means of further promoting the participation of groups underrepresented in biology. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.