Overexpression of a heat stress inducible, wheat myo-inositol-1-phosphate synthase 2 (TaMIPS2) confers tolerance to various abiotic stresses in Arabidopsis thaliana

Myo-Inositol phosphate synthase (MIPS) enzyme catalyses rate limiting step of myo-inositol (MI) biosynthesis. MIPS by-products are involved in many plant processes. In this study, TaMIPS2 identified from a heat subtractive cDNA library from wheat has been functionally characterized. To investigate the importance of TaMIPS2 during heat stress tolerance, TaMIPS2 overexpression transgenics were raised in Arabidopsis which were analysed physiologically and morphologically under different abiotic stress conditions. MIPS enzyme assay revealed the level of inositol in transgenics and of other soluble sugars as quantified by HPLC. Analysis of overexpression transgenics under different stress condition revealed that TaMIPS2 transgenic have reduced sensitivity to heat stress. This is the first report indicating a role of myo-Inositol during heat stress. The analysis of transgenic lines of TaMIPS2 suggests its additional role under other environmental stresses.