Dehydration-Responsive Reversible and Irreversible Changes in the Extracellular Matrix: Comparative Proteomics of Chickpea Genotypes with Contrasting Tolerance

Dehydration is the most crucial environmental factor that limits plant growth, development, and productivity affecting agriculture throughout the world. Studies on genetic variations for dehydration tolerance in plants is crucial because divergent cultivars with contrasting traits aid the identification of key cellular components that confer better adaptability. The extracellular matrix (ECM) is a dynamic structure that serves as the repository for important signaling components and acts as a front-line defense. To better understand dehydration adaptation, a proteomic study was performed on the extracellular matrix of ICCV-2, a dehydration-susceptible genotype of chickpea. The proteome was generated with ECM-enriched fractions using two-dimensional gel electrophoresis. The LC-ESI-MS/MS analysis led to the identification of 81 dehydration-responsive proteins. The proteome was then compared with that of JG-62, a tolerant genotype. Comparative proteomics revealed genotype-specific expression of many proteins involved in a variety of cellular functions. Further, the reversible and irreversible changes in the proteomes revealed their differing ability to recover from dehydration-induced damage. We propose that cell wall restructuring and superior homeostasis, particularly the management of reactive oxygen species, may render better dehydration-adaptation. To our knowledge, this is the first report on the comprehensive comparison of dehydration-responsive organellar proteome of two genotypes with contrasting tolerance.