A Novel Class of Programmable Hormone-Responsive Transcription Factors to Re-Engineer Plant-Environment Interactions

Human society is built on a plethora plant products from essentials such as food and feed stocks to luxuries such as pharmaceuticals and textiles. The indiscriminant use of pesticides and fertilizers coupled with the escalating effects of climate change has created a rapidly changing agricultural environment that gravely threatens the sustained productivity of crops. To address this challenge there is a need for tunable biological control systems that can connect the plants native perception of its environment to appropriate natural or synthetically engineered responses. In this work we present a novel class of hormone-responsive CRISPR-based transcription factors and demonstrate their function in Arabidopsis thaliana. We explore the modular nature of the transcription factors by testing a range of different transcriptional repressor domains and hormone responsive degrons. Using this approach we are exploring how hormone fluxes triggered by the environment can be coupled in a tunable fashion to the expression of a gene of choice. Specifically we are interested in coupling the perception of the plant hormone jasmonate isoleucine, which is released upon insect predation, to the expression of insect defense mechanisms. We are also interested in rewiring developmentally triggered fluxes of the plant growth hormone auxin to the expression of novel genes, to re-engineer plant development. Using this new class of transcription factors we hope to design biological control systems that will make crops more robust to a rapidly changing environment.