Environmental stress, such as drought, salinity and pathogen attack are the principle causes of reduced crop productivity worldwide. Plant adaptation to stress is dependent upon the initialization of cascades of molecular networks involved in stress perception, signal transduction and the expression of specific stress-related genes. In order to grow enough crops to feed the growing population it will be essential to understand the molecular mechanisms responsible for stress tolerance. The PRESTA project, which spans several lab groups within Warwick as well as the Universities of Essex and Exeter, is aimed at elucidating signalling networks that regulate plant responses to environmental stress. Work undertaken at Warwick HRI has already generated several large microarray datasets that follow gene expression changes over time in response to development/senescence and Botrytis infection. Additional datasets (drought, high light, Pseudomonas infection) will be available in the near future. These data are now being used to build models to predict transcriptional networks.

Dramatic variations in gene expression are observed at the onset of stress and senescence, with different groups of genes showing different expression time-courses. This observation must, for a large part, be down to the action of different transcription factors (TFs) or combinations of TFs binding to the promoters of genes in each group. TF binding is specified by short DNA sequence motifs typically present upstream of the transcription start site of a gene. The main aim of this project is to identify and characterize promoter motifs and motif patterns that can explain expression patterns observed in microarray data and use these data to validate and extend existing gene regulatory networks.