Our research examines the structure/function relationships of plasmodesmata (PD) and the basic mechanisms by which macromolecules pass between higher plant cells. Recent work has focussed on the formation of primary and secondary PD, and in the development of novel approaches for studying PD dynamics non-invasively. My group also researches the mechanisms by which plant-viral genomes pass between cells, with emphasis on the movement of the filamentous viruses potato virus X (PVX) and tobacco mosaic virus (TMV). Specific emphasis is placed on the role of viral movement proteins in facilitating the passage of viral genomes through PD. Additional interests include studies of the movement of non-cell autonomous plant proteins, and the isolation of novel protein components from PD using proteomics and viral-vector based technologies. The group also studies the long-distance movement of macromolecules in plants with emphasis on the nature and regulation of phloem unloading in sink organs such as developing roots and storage organs. We are also interested in the biotechnological uses of viral vectors as protein delivery vehicles in plants.

To increase our understanding of the control of cell-to-cell transport in plants, we use a diversity of approaches that encompass molecular biology, cell biology, plant virology and confocal imaging. Recently we have exploring a wide range of novel imaging approaches, based on fluorescent reporter technologies, to track RNA and protein movement within living plant cells. These include the use of a novel fluorescent reporter, iLOV, derived by molecular evolution from a plant phototropin (collaboration with Dr. John Christie, University of Glasgow), the development of an in vivo reporter of viral RNA based on the RNA-binding protein, Pumilio, and the use of direct RNA labelling protocols coupled to microinjection. In current work, we are exploring the use of novel photactivatable flouresecent reporters,coupled to photoactivation localisation microscopy (PALM; collaboration with Dr. Cristina Flors, School of Chemistry, University of Edinburgh) to conduct super-resolution studies of PD development and virus cell-to-cell movement.