HYDROSENSING · DISCOVERING HOW PLANTS SENSE WATER STRESS

Water stress is an increasing probleWater stress is an increasing problem for global agriculture given the impact of climate change. Despite the fundamental importance of water, exactly how plants sense its availability remains unknown. This new knowledge is vital for designing more climate resilient crops, yet currently remains a critical gap in scientific understanding. Our unique synergy is ideal to take on this ambitious project and discover how plants sense water after identifying membrane proteins from a proof-of-principle multi-targeted genetic screen designed to reveal components of the water-sensing (hydrosensing) machinery. We hypothesise changes in plant hydraulic fluxes driven by transient water stress are sensed by a specialised cell type – termed phloem companion cells - that controls the synthesis and release of the abiotic stress signal ABA. Release of ABA by water stress is triggered by perturbations in plasma membrane-cell wall contact sensed by kinases like THESEUS1 (THE1) and additional missing components, which we will identify using our custom multi-targeted CIRSPR libraries. Our discoveries will unlock the mechanism enabling sensing of the most important molecule on the planet, WATER, in the most abundant lifeform biomass-wise, PLANTS.Solving how plants sense water demands a highly inter-disciplinary strategy that goes beyond the cutting edge by pioneering the development of innovative genome editing, functional imaging and structural biology approaches. The breadth and depth of capabilities and expertise to undertake this strategy necessitates a synergistic partnership between world-leading groups to go beyond the current state of the art. By pursuing this high-risk/high-gain strategy, our project promises to reveal common ‘design principles’ that underpin the core mechanism(s) for water stress signalling in plants. This new knowledge is crucial for international efforts to design climate-resilient crops and underpin global food security.