Dissection and manipulation of metabolic signalling pathways

The partitioning of resources between different plant organs and compounds is an important determinant of crop quality. We are attempting to change resource partitioning in crop plants by manipulating the cellular mechanisms involved in metabolite sensing and signalling. One of the proteins involved is SnRK1 (sucrose nonfermenting-1-related protein kinase 1), so-called because of its homology and functional similarity with sucrose non-fermenting 1 (SNF1) of yeast. SnRK1 is a protein kinase that plays a key role in the global control of plant carbon metabolism. Here we review studies on the characterisation of SnRK1 gene families, SnRK1 regulation and function, and the identification of SnRK1-interacting proteins. We also describe some potential applications of manipulating SnRK1 activity, including controlling sprouting in stored potato tubers, inducing male sterility in barley and increasing sterol levels in oilseeds.