We have two speakers on Sept. 23! See information below:
Speaker 1: Jiachen Li, master's student, Department of Computational Medicine & Bioinformatics, Zhang Lab
Title: Chance and necessity in evolution: how repeatable is phenotypic evolution?
Description: Assessing the relative roles of chance and necessity in evolution is of wide interest, but it requires evolving the same population under the same environment multiple times—a virtually impossible task in nature that has been repeatedly accomplished in the laboratory. Capitalizing on the transcriptome data collected from experimental evolution of replicated populations spanning distinct environments, I investigate the evolutionary repeatability of hundreds of thousands of gene expression traits in a prokaryotic and five eukaryotic species.
Speaker 2: Dr. Yang Li, EEB Postdoctoral Fellow, Zhang Lab.
Title: Navigability of thousands of adaptive landscapes of RNA and protein expressions by trans-regulatory mutations
Description: Gene expression evolution relies on regulatory mutations. Past studies showed that optimizing gene expression by positive selection on cis-regulatory mutations is relatively easy because the corresponding adaptive landscapes are quite smooth, but a comparable study of trans-regulatory mutations is lacking. Analyzing the transcriptomes and proteomes of 16 yeast strains carrying all combinations of four auxotrophic mutations, we respectively construct 5,923 and 446 adaptive landscapes of mRNA and protein expressions where neighboring genotypes differ by a trans-regulatory mutation. We find that mRNA expression is less optimizable by trans- than cis-mutations, which may partially explain why trans-changes are rarer than cis-changes in gene expression evolution. Interestingly, the protein expression landscapes are substantially more navigable than the mRNA expression landscapes, suggesting that, for protein-coding genes, the evolvability of gene expression is even higher than the current estimate from adaptive landscapes of mRNA expression. This high evolvability may have contributed to the prominence of gene expression changes as a mechanism of evolutionary adaptation.
Speaker 1: Jiachen Li, master's student, Department of Computational Medicine & Bioinformatics, Zhang Lab
Title: Chance and necessity in evolution: how repeatable is phenotypic evolution?
Description: Assessing the relative roles of chance and necessity in evolution is of wide interest, but it requires evolving the same population under the same environment multiple times—a virtually impossible task in nature that has been repeatedly accomplished in the laboratory. Capitalizing on the transcriptome data collected from experimental evolution of replicated populations spanning distinct environments, I investigate the evolutionary repeatability of hundreds of thousands of gene expression traits in a prokaryotic and five eukaryotic species.
Speaker 2: Dr. Yang Li, EEB Postdoctoral Fellow, Zhang Lab.
Title: Navigability of thousands of adaptive landscapes of RNA and protein expressions by trans-regulatory mutations
Description: Gene expression evolution relies on regulatory mutations. Past studies showed that optimizing gene expression by positive selection on cis-regulatory mutations is relatively easy because the corresponding adaptive landscapes are quite smooth, but a comparable study of trans-regulatory mutations is lacking. Analyzing the transcriptomes and proteomes of 16 yeast strains carrying all combinations of four auxotrophic mutations, we respectively construct 5,923 and 446 adaptive landscapes of mRNA and protein expressions where neighboring genotypes differ by a trans-regulatory mutation. We find that mRNA expression is less optimizable by trans- than cis-mutations, which may partially explain why trans-changes are rarer than cis-changes in gene expression evolution. Interestingly, the protein expression landscapes are substantially more navigable than the mRNA expression landscapes, suggesting that, for protein-coding genes, the evolvability of gene expression is even higher than the current estimate from adaptive landscapes of mRNA expression. This high evolvability may have contributed to the prominence of gene expression changes as a mechanism of evolutionary adaptation.
| Building: | Biological Sciences Building |
|---|---|
| Event Type: | Workshop / Seminar |
| Tags: | biological science, Biology, Biosciences, Bsbsigns, department of ecology and evolutionary biology, Discussion, ecology, Ecology & Biology, Ecology And Evolutionary Biology, eeb, evolutionary biology |
| Source: | Happening @ Michigan from Ecology and Evolutionary Biology, EEB Tuesday Lunch Seminars |
