Heat stress associated antioxidant isoenzymes in wheat: Expression and proteomics

Abiotic stress leads to change in the expression and activities of number of proteins which are involved in defense mechanism against stresses. Qualitative and quantitative changes in proteins might play a role in signal transduction, antioxidative defence, heat shock, metal binding or osmolyte synthesis. Here, 22 wheat genotypes were screened for its cell membrane stability (CMS), out of which C-306 showed the maximum CMS value of 74%. Protein profiling revealed the expression of many new and existing proteins in C-306 cultivar compared to PBW343 under differential heat shock (HS). An altered protein expression was also observed in tolerant and susceptible cultivars at different stages of growth. Isoenzymic profiling revealed the expression of many new isoenzymes of ascorbate peroxidase and superoxide dismutase in C-306 compared to PBW343 in response to heat shock. A stage specific analysis showed the maximum activity of different antioxidant isoenzymesat pollination and seed hardening stages. SODs plays central role in regulating defense mechanism and need to be further characterized.