CAREER: Mechanisms and consequences of Genotype by Environment interaction in a model grass

Solar energy captured by plants is the central currency of life on Earth. Through a set of elegant chemical reactions, plants use solar energy to power the conversion of atmospheric carbon dioxide into stable sugars. These organic compounds, in turn, are used by the plant for growth and reproduction.

Plant growth and reproductive output feed the world, and plant metabolism is a key determinant of atmospheric composition. Understanding how these three fundamental activities – growth, metabolism, and reproduction -- are controlled by genes and the environment is a fundamental challenge for science to ensure the resilience of ecological and agricultural systems.

This project uses a model grass species, Brachypodium distachyon, to disentangle the complex interactions between plant genetics and environment. There are three broad aims. First, to study the genetic basis of plant response to several environmental stressors to ask whether certain combinations of plant traits might be difficult to achieve over evolutionary time scales, or during breeding for crops.

Second, to use genomics to identify specific genes – and interactions among genes – which control plant response to environmental stress. Finally, to study whether and how plants buffer the potentially destabilizing effects of environmental stress on their growth. These research aims will be complemented and expanded by developing a new undergraduate laboratory class, representing the first dedicated plant biology class at MIT.

In this class, students will design and perform experiments exploring plant biochemistry, development, and responses to climate change.

This project investigates the molecular, physiological, and developmental basis of genotype by environment interaction, GxE. GxE is the observation that genetically distinct individuals respond to environmental cues in different ways. The project leverages the considerable genetic and genomic resources in the model grass species Brachypodium distachyon towards three specific aims.

First, to ask how allelic function in one environment relates to functions in a second environment and whether genetic correlations between two environments might constrain organismal response to novel or challenging environments. These experiments use quantitative genetic approaches to understand the genetic architecture of environmentally responsive traits.

Next, to investigate how interactions among genes at the molecular level shapes GxE, asking whether GxE in the transcript abundance of individual genes drives GxE in gene regulatory networks. Finally, to decompose the drivers of Relative Growth Rate to ask how genetic and environmental perturbations in key traits are (or are not) buffered to maintain stable RGR.

These research aims will be complemented and extended by two educational aims. To develop the first stand-alone plant science class at MIT and introduce students to data generation and analysis in plants. This course specifically asks students to describe now genetics and the environment interact to produce phenotypic diversity, and the data generated will be used directly in the research aims of this project.

In the second education aim, a field-based learning experience in Boston’s Arnold Arboretum will be developed for students to observe and interpret trait diversity in plants. This award was co-funded by the Plant Genome Research Program.

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.