Modeling guard cell-to-leaf scales with OnGuard2

While much is known about the processes involved in stomatal movement and the processes involved in the transpiration of leaves, there has been no framework to bridge this micro-macro divide. Wang and colleagues bridge this divide through OnGuard2, a quantitative systems platform that uses the molecular mechanisms of the guard cell (ion transport, metabolism, signaling) to understand the transpiration of the leaf. They show that OnGuard2 reproduces experimentally-derived foliar transpiration and stomatal kinetics of different Arabidopsis lines, including wild-type, slac1 Cl^– channel mutant and ost2 H⁺-ATPase mutant lines. This single framework can be used to understand stomatal physiology in greater detail, and can be used to connect guard cell membrane transport to plant water relations. (Summary by Julia Miller) Plant Cell 10.1105/tpc.17.00694