Submitted to: Plant Biology Annual Meeting
Publication Type: Abstract only
Publication Acceptance Date: 7/7/2007
Publication Date: 7/11/2007
Citation: Kottapalli, K.R., Burow, G.B., Burke, J.J., Payton, P.R., Puppala, N., Rakwal, R., Burow, M. 2007. Proteomics of water-deficit stress in US peanut mini core accesions[abstract]. Plant Biology 2007. Chicago, Illinois. July 7-11, 2007. Interpretive Summary:
Technical Abstract: Peanut (Arachis hypogaea L.) accessions from the US mini core collection were analyzed for differentially expressed leaf proteins during reproductive stage under water-deficit stress. Accessions showing tolerant and susceptible responses to stress were selected based on a bioassay involving chlorophyll fluorescence yield under elevated respiratory demand, water use efficiency and specific leaf area. One- and two-dimensional gel electrophoresis (1- and 2-DGE) was performed on leaf soluble protein extracts of selected tolerant, intermediate and susceptible accessions. 1-D gel immunoblotting revealed a significant decrease in the oxidative-stress related ascorbate peroxidase (APX) in the tolerant accession and low molecular weight heat shock protein (HSP 30) in the susceptible accession under stress. A total of 40 and 79 protein bands/spots from 1D and 2 D gels, respectively, were excised for analysis by using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and by MS/MS analysis, and 35 non-redundant proteins were identified. The photosynthetic enzymes, ribulose 1,5-biphosphate carboxylase-oxygenase and carbonic anhydrase were induced under stress, suggesting possible photosynthetic adaptation in tolerant accessions. Lipoxygenase involved in jasmonic acid synthesis was suppressed, while a signaling protein, oxygen evolving enhancer 2(OEE2) was induced under water stress. Interestingly, acetyl-CoA carboxylase carboxyl transferase, an enzyme of fatty acid biosynthesis, was induced only in the tolerant accession, indicating its putative role in the tolerance response. The identified proteins from peanuts leaves and their corresponding genes can be incorporated in the marker assisted breeding project for drought tolerance in peanuts.