How cells talk to each other

Plants are sessile organisms that have developed integrated and sophisticated signalling systems to respond to their environment. Plant cells are immobile and thus must relay information between cells and tissues by the deployment of mobile molecules or propagating signalling cascades. By such mechanisms plants can activate a stress response far from the site of detection, leading to changes in gene expression in cells that have not yet but are likely to encounter the stress. In this way, a tissue in a leaf can be primed for defence following detection of a pathogen in a different leaf or the root.

One mechanism by which plants signal between distal tissues is by the propagation of calcium waves. Models exist which suggest that a combination of calcium ions and reactive oxygen species work in partnership to propagate this signal, but this requires further testing as recent data suggests some of the underlying assumptions are incorrect. In particular, the role of plasmodesmata (membrane-lined cytoplasmic connections between the cells) and the signalling distance of both classes of molecules in the absence of propagation need further investigation.

This project will use state-of-the-art imaging technologies to investigate the role of plasmodesmata (membrane-lined cytoplasmic connections between the cells), and the signalling distance of reactive oxygen species and calcium ions, to establish the mechanisms underlying long distance calcium signalling in plants. Mathematical modelling will be used (in collaboration) to integrate this information to form testable predictions to guide further hypotheses and experimentation.