Climate adaptation in Arabidopsis thaliana through evolution of transcription regulation

ended

Differences in gene expression play a key role in generating the phenotypic variability needed for adaptation. During evolution, the coding sequence of genes evolves on average much slower than their expression patterns, thus transcriptional regulation can be especially important for rapid adaptation to a new environment. Climate is a major factor for plant adaptation, and both the dispersal of a plant from its native origin as well as climate change will often lower its fitness. Thus, understanding how gene expression patterns are modified to facilitate life in adverse climates would shed light on the trade-offs limiting adaptation. Studying how evolution has shaped plant transcriptomes so that these plants can grow in different ecological niches and their potential to adapt to a changing climate requires a large base of natural variability information. This has recently been accumulated for Arabidopsis thaliana, a model for genetic and evolutionary studies. In the proposed project I will use genomic and transcriptomic data from the A. thaliana 1001 Genomes Project, new measurements of gene expression under water deprivation, as well as newly available data on gene-regulation and field fitness, to define how gene expression is shaped by climate and the genetic potential to adapt to new environments. I will address the following: (1) In natural populations, how do gene expression patterns of individuals correspond to the particular adapted climates? (2) What is the genetic basis for the transcript differences and how is it reflected in modifications to the transcriptional network? (3) Can knowledge of climate-transcript variation relationships be predictive of individual strains more likely to survive in a new climate? As climate is changing due to global warming, the understanding of mechanisms by which plants adapt to climate becomes even more important in agriculture and in natural populations, and this project aims to illuminate the role of a central mechanism.