The ABACUS biosensor used with confocal microscopes can be used to visualise the levels of the plant hormone abscisic acid in Arabidopsis seedlings. Image by Jim Rowe.
Abscisic acid (ABA) dynamics
Visualising ABA signalling
In plants, abscisic acid (ABA) is a key regulator of water use efficiency and also controls key developmental decisions such as the timing of germination and the patterning of root architecture to match environmental conditions. ABA accumulates under abiotic stress to help the plant to adapt its development, such as promoting root growth during drought to help the plant forage deeper into the soil to find water. Despite these understandings, several fundamental questions remain unanswered: which cells accumulate these hormones in response to key stimuli and when do these accumulations begin and end?
Using ABACUS, the Jones team has begun to unravel how ABA concentrations are patterned spatially or change over time. The next step is to use a genetic approach to dissect out the quantitative contributions of specific ABA biochemical activities on these patterns and dynamics.
ABACUS biosensor development
To overcome the lack of high-resolution, sensitive reporters, the Jones Team is developing next-generation biosensors for ABA with high affinity, high signal-to-noise and increased orthogonality. This advancement is already opening new research directions.