Poster: Proteomics

Abs # 967: Proteomic Analysis of Cultured Medicago truncatula Cells

Presenter:	Elmer, Aaron M., amelmer@noble.org
Authors	Elmer, Aaron M. (A)   Lei, Zhentian  (A)   Sumner, Lloyd W. (A)
Affiliations:	(A): The Samuel Roberts Noble Foundation

Plant secondary metabolism consists of a complex network of metabolic pathways culminating in a diverse population of bioactive products. While basal levels and flux through these pathways exist to aid in plant growth, development, and defense; regulatory mechanisms are present that respond to pathogens and herbivores by altering expression of existing biosynthetic pathways or by inducing novel pathways. Many of these biosynthetic compounds have medicinal applications such as chemotherapy and hormone replacement. Legumes, including the Medicago species, provide an excellent source of secondary metabolites and serve as major food sources for both humans and animals. Because of the agricultural and medicinal importance of secondary metabolism and secondary metabolic enzymes in legumes, our lab has begun to profile the proteome of cultured Medicago truncatula cells using 2D gel electrophoresis. Proteins extracted from Medicago truncatula suspension culture cells were focused on 24 cm, pH 3-10 non-linear, Immobiline™ DryStrips. Second dimension SDS-PAGE was performed using 12.5% acrylamide-PDA gels and the Ettan™ DALTtwelve system. Initial efforts are focused on the identification of approximately 1300 proteins from cell suspension cultures using LC-MS/MS. The identified proteins include enzymes from almost all subcellular compartments, structural proteins from the cytoskeleton, proteins involved in perception and signal transduction, transcription factors, and trafficking proteins. The cataloged proteins will be used as a starting point for identification of novel proteins induced by elicitation with methyl jasmonate as well as the quantification of kinetic changes in key proteins involved in the metabolic and signal transduction pathways.