Protein profile changes under salt-boron toxicity and its regulation by hydrogen peroxide and glutathione in pigeonpea (Cajanus cajan L.)

Two genotypes of pigeon pea (Cajanus cajan L. Millsp.), salt tolerant Manak, (H77–216) and salt sensitive ICPL 88039 were subjected to treatment solutions with distilled water (C), H₂O₂ (100 μM; H), Glutathione, GSH (500 μM; G), H₂O₂ (100 μM) + GSH (500 μM) superimposed with S₀B₀ (DW), S₀B₁₀ (0 mM NaCl + 10 mM B as Na₂B₄O₇.10H₂O, S₁₀₀ + B₀ (100 mM NaCl + 0 mM B) and S₁₀₀B₁₀ (100 mM NaCl + 10 mM B) at the seedling stage in a BOD incubator at 27 ± 10C in dark for 96 h. Proteins from coleoptiles and radicles were resolved by SDS-PAGE. In tolerant cultivar Manak two proteins of molecular weight 67.6 and 81.1 kDa disappeared in S₀B₁₀ C, however 67.6 kDa reappeared with S₀B₁₀ H and S₀B₁₀ H +G treatments. Similarly two bands of 51.2 and 87.0 kDa disappeared due to S₁₀₀ treatment but only 51.2 kDa reappeared with S₁₀₀B₀H and S₁₀₀B₀ H +G treatments. Likewise in radicle of Manak a 66.6 kDa protein disappeared with S₀B₁₀ C but same protein reappeared with H₂O₂, Glutathione, H₂O₂ + GSH treatments. Even S₁₀₀B₁₀ C treatment repressed 79.8 kDa protein in ICPL 88039 but got recovered with H₂O₂, Glutathione and H₂O₂ + GSH treatments. These observations accord credence to step-up regulation of protein synthetic machinery in pigeonpea by H₂O₂ and glutathione under salt-B toxicity conditions.