NSF Postdoctoral Fellowship in Biology: Investigating the Genetic and Evolutionary Dynamics Producing Patterns of Trade-off Conditionality

Visher, Elisa, Berkeley CA

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2022, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the Fellow that will contribute to the area of Rules of Life in innovative ways. The Fellow’s research will focus on understanding the genetics of trade-offs in microbes to better understand patterns of diversity in nature and constraints to adaptation. The research will therefore have consequences for understanding adaptation to changing environments, anti-microbial resistance evolution, and disease emergence. The Fellow will also develop an undergraduate research program to contribute to training the next generation of researchers in biology, including those currently underrepresented in STEM disciplines. This research project will explore how trade-off shapes change over time, depend on evolutionary history, and determine coevolutionary diversification. A key goal of the project will be to understand how genetic processes determine phenotypic trade-offs, and how these processes might explain observed patterns in the conditionality of trade-offs. This will be achieved by using barcoding methods in two model systems (one evolutionary yeast system and one coevolutionary Pseudomonas and phage system) to conduct high-throughput fitness assays in multiple environments (or on coevolved partners) and track lineage dynamics. The first objective will determine how trade-off shapes change over time by further evolving existing first-step yeast mutants in specialist and generalist directions and periodically reassessing the Pareto front of evolving genotypes. The second objective will evolve yeast lineages in fluctuating environments and determine how environmental heterogeneity influences the joint distribution of mutational fitness effects. The final objective will determine how trade-off determines coevolutionary dynamics by developing methods to conduct high-throughput fitness assays and lineage tracking in Pseudomonas and phage model systems. The Fellow will gain training experience with computational and genetic methods that includes high-throughput assays and building barcoded libraries. Finally, the Fellow will contribute to broadening participation in STEM and improving undergraduate research training by developing an undergraduate research program; this will provide transparent, accessible, and supported entry into biological science research through a centralized portal advertising research opportunities and cohort-based research and professional skill training programs. 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.