Identification of candidate phosphorus stress induced genes in Phaseolus vulgaris through clustering analysis across several plant species.

Common bean (Phaseolus vulgaris L.) is the world's most important grain legume for direct human consumption. However, the soils in which common bean predominate are frequently limited by the availability of phosphorus (P). Improving bean yield and quality requires an understanding of the genes controlling P acquisition and use, ultimately utilising these genes for crop improvement. Here we report an in silico approach for the identification of genes involved in adaptation of P. vulgaris and other legumes to P-deficiency. Some 22 groups of genes from four legume species and Arabidopsis thaliana, encoding diverse functions, were identified as statistically over-represented in EST contigs from P-stressed tissues. By combining bioinformatics analysis with available micro / macroarray technologies and clustering results across five species, we identified 52 P. vulgaris candidate genes belonging to 19 categories as induced by P-stress response. Transport-related, stress (defence and regulation) signal transduction genes are abundantly represented. Manipulating these genes through traditional breeding methodologies and / or biotechnology approaches may allow us to improve crop P-nutrition.