Proteomic analysis of the drought stress response in barley (Hordeum vulgare L.) using DIGE technology

Drought is one of the most important constraints on the growth and productivity of barley (Hordeum vulgare L.). A proteome analysis based on 2-D gel electrophoresis was performed in order to identify drought stress responsive proteins. Pot experiments were arranged in randomized block factorial design with two watering treatments, control and drought conditions, and three barley genotypes. Plants were well-watered until the four leaf stage and then exposed to severe drought stress for 10 days. The overall effect of drought was highly significant (P<0.01), as determined by dry matter, fresh matter, relative water content and proline free content. To study protein expression changes in response to drought stress, proteome analysis was performed based on DIGE technology with the inclusion of an internal standard. About 768 spots were detected on CyDyes gels, of these 37 spots showed significantly changes as genotypes or genotype × irrigation levels effects. Finally mass spectrometry analyzing using MALDI-TOF-TOF led to the identification of 19 proteins. The functional of these proteins were identified as defense, energy, metabolism, cell structure, signal transduction and cell differentiation.