Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: 1/10/2009
Publication Date: 1/10/2009
Citation: Payton, P.R., Kottapalli, K.R., Rakwal, R., Shibato, J., Puppala, V., Burow, M. 2009. Transcriptome and proteome response to water-deficit stress in peanut (Arachis sp.)[abstract]. Plant and Animal Genome Conference. January 10-14, 2009, San Diego, California. CDROM.
Technical Abstract: Peanut genotypes from the U.S. mini-core collection were screened under water-deficit stress conditions and two lines, COC041 (Tolerant) and COC166 (Susceptible) were selected for gene expression and protein profiling studies. For transcript profiling, we have developed a high-density oligonucleotide microarray (Agilent Technologies) using 40,000 publicly available peanut ESTs. Leaf samples from plants exposed to water deficit were collected at 0.5, 1, 3, 5, and 5 days. Initial analyses of transcript response to water-deficit in leaf revealed significant differences between tolerant and susceptible germplasm. A total of 623 transcripts showed genotype-specific expression patterns and are currently being analyzed. 1- and 2-DGE on leaf soluble protein extracts from stressed and fully irrigated plants resulted in the identification of 23 and 70 protein bands/spots from 1-D and 2-D gels, respectively, MALDI-TOF-MS and Q-TOF-MS/MS analysis of 49 non-redundant proteins identified a variety of water-deficit stress response mechanisms in peanut. Lipoxygenase and 1L-myo-inositol-1phosphate synthase proteins, which aid in inter- and intracellular stress signaling, were more abundant in tolerant genotypes under water-deficit stress compared to both susceptible and well-watered control plants. Acetyl-CoA carboxylase, a key enzyme of lipid biosynthesis, increased in relative abundance along with a corresponding incrase in epicuticular wax content in the tolerant genotype. Additionally, there was a marked decrease in the abundance of several key photosynthetic proteins in the tolerant genotype, along with a concomitant decrease in net photosynthesis in response to water-deficit stress.