Understanding the regulation of sulfur nutrition – from sulfate transporter genes to the field
Part of book or chapter of book
- Publisher: Backhuys Publishers
Sulfur is taken up by the plant and transported in the cell and around the plant mainly as sulfate. These processes are dependent on the sulfate transporters, and therefore the transporters have a central role in the management of plant sulfur nutrition for optimisation of growth. A large number of plant sulfate transporters have been cloned and comparative sequence analysis indicates that although they are all related, they cluster into a number of discrete sub-types. Within any plant species there appears to be approximately 14 members of this gene family; functional and expression data suggest that there is little redundancy and that each transporter has a specialised role. Furthermore the expression of many of the transporters is regulated by the sulfur-nutritional status of the plant; the regulation serves to optimize acquisition and utilization of sulfate. The mechanisms facilitating this regulation have been subject to intense investigation. One generally accepted model based on metabolite feedback regulation of gene expression is presented and critically evaluated. Genomic approaches focussed on identification of sensing and signal transduction pathways are described; transcriptome analysis of both field and controlled environment grown wheat has enabled the identification of many nutrient-regulated genes, including potential candidates for regulatory components.