Plant & Animal Genomes XIV Conference

January 14-18, 2006
Town & Country Convention Center
San Diego, CA

Gene Discoveries And Integrated Functional Genomics Studies Of Medicago truncatula Responses To Biotic And Abiotic Stress

Mohamed A. Farag , Zhentian Lei , Corey D. Broeckling , David V. Huhmand , Marina Naoumkina , Bettina Deavours , Bonnie S. Watson , Satish Nagaraj , Richard A. Dixon , Lloyd W. Sumner

  The Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401 USA

An integrated functional genomics approach is being used to study the response of the model legume Medicago truncatula following biotic and abiotic elicitation at the mRNA, protein and metabolite levels. M. truncatula suspension cell cultures were separately treated with methyl jasmonate, yeast cell wall extract, or UV light. Samples were collected at 21 time points following each elicitation and analyzed at the metabolite, protein, and mRNA levels. This presentation will focus on gene discoveries that were initially revealed during mining of the proteomic and metabolomic data. Metabolomic data were collected using gas chromatography-mass spectrometry (GC/MS) and and liquid chromatography-mass spectrometry (LC/MS). Proteomic data was collected using two-dimensional polyacrylamide gel electrophoresis (2-DE). Discoveries at the protein and metabolite levels were correlated with mRNA levels obtained using 16K oligonucleotide microarray analysis to identify putative relationships between metabolites, proteins, and genes. Recombinant proteins were generated for each putative gene target in E. coli and assayed for enzymatic activity. The results yielded multiple new gene discoveries related to secondary metabolism. Specific examples will be provided relative to phenylpropanoid and lignin biosynthesis.