Abstract

Knowledge-Based Identification of Plant Stress Regulators

Lorenz Bülow, Bioinformatician and Database Manager, Julius Kühn-Institut

Basic knowledge on plant gene regulation upon abiotic and biotic stresses is essential for modern plant breeding approaches since these stresses are key factors that reduce crop plant yield. Binding of transcription factors to cis-regulatory sequence elements in promoters is considered to be a major mechanism of gene expression regulation; however, our knowledge on the specific molecular regulators involved in stress response is still insufficient. The main current goal is to combine existing and to develop novel complementary in silico and experimental methods towards an integrated knowledge-based approach to decipher control of plant gene expression. Microarray experiments on most important plant stresses are publicly available and bioinformatics tools identified gene sets co-regulated by single or combinations of different stresses. Arabidopsis thaliana promoter sequences were used to determine conserved sequences and to predict cis-regulatory elements within the promoters of these genes. A further bioinformatics analysis yielded putative transcription factors expected to bind to the predicted cis-elements. Several heterologous expression systems were used to experimentally verify the predictions and provided evidence for the transferability of the approach from a model plant system to crop species.