Showing papers by "Nagib Ahsan published in 2010"

Tissue-specific defense and thermo-adaptive mechanisms of soybean seedlings under heat stress revealed by proteomic approach.

Abstract: A comparative proteomic approach was employed to explore tissue-specific protein expression patterns in soybean seedlings under heat stress. The changes in the protein expression profiles of soybean seedling leaves, stems, and roots were analyzed after exposure to high temperatures. A total of 54, 35, and 61 differentially expressed proteins were identified from heat-treated leaves, stems, and roots, respectively. Differentially expressed heat shock proteins (HSPs) and proteins involved in antioxidant defense were mostly up-regulated, whereas proteins associated with photosynthesis, secondary metabolism, and amino acid and protein biosynthesis were down-regulated in response to heat stress. A group of proteins, specifically low molecular weight HSPs and HSP70, were up-regulated and expressed in a similar manner in all tissues. Proteomic analysis indicated that the responses of HSP70, CPN-60 β, and ChsHSP were tissue specific, and this observation was validated by immunoblot analysis. The heat-responsive s...

Ozone stress-induced proteomic changes in leaf total soluble and chloroplast proteins of soybean reveal that carbon allocation is involved in adaptation in the early developmental stage.

Abstract: Considerable soybean yield losses caused by ozone (O3) stress have been demonstrated by large-scale meta-analyses of free-gas concentration enrichment systems In this study, comparative proteomic approach was employed to explore the differential changes of proteins in O3 target structures such as leaf and chloroplasts of soybean seedlings Acute O3 exposure (120 parts-per-billion) for 3 days did not cause any visible symptoms in developing leaves However, higher amounts of ROS and lipid peroxidation indicated that severe oxidative burst occurred Immunoblot analysis of O3-induced known proteins revealed that proteins were modulated before symptoms became visible Proteomic analysis identified a total of 20 and 32 differentially expressed proteins from O3-treated leaf and chloroplast, respectively Proteins associated with photosynthesis, including photosystem I/II and carbon assimilation decreased following exposure to O3 In contrast, proteins involved in antioxidant defense and carbon metabolism increased The activity of enzymes involved in carbohydrate metabolism increased following exposure to O3, which is consistent with the decrease in starch and increase in sucrose concentrations Taken together, these results suggest that carbon allocation is tightly programmed, and starch degradation probably feeds the tricarboxylic acid cycle while the photosynthesis pathway is severely affected during O3 stress

Proteomics application of crops in the context of climatic changes. Food Res Int

Abstract: Abstract Abiotic stress caused by global climate change varies widely, which negatively affect crops growth and productivity throughout the world. Environmental changes can alter plant’s physiological state and trigger several signaling pathways for adaptation to unfavorable conditions. Plant response to abiotic stress includes changes in protein expression and post-translational modification of proteins to activate their defense system against the challenges. Research on plant proteomes has provided beneficial information for a comprehensive understanding of the protein networks in plants in response to external stimuli. Large-scale proteomics is a powerful approach for studies of complex biological processes in which a number of proteins take part; proteome analysis of sub-cellular structures and modified proteins has enabled identification of novel components of plant stress responses that had not previously been discovered. In this review, we have discussed the recent developments of crop proteomics in the context of several climatic factors including photosynthetic stress, air pollutants, thermal stress including heat and cold, and osmotic stress, including drought, salt, and flooding stress, and metal stress. The aim of this review is to take a snapshot of several proteomic approaches in crop plants that provide a comprehensive list of components affected by certain abiotic stresses in climate. The biological relevance of these proteins in regard to plant stress tolerance will be described as well.