Gene isolation and expression analysis of galactinol synthase from proso millet (Panicum miliaceum L.)

Abstract Drought is the major devastating stress affecting plant growth and development. The plant develops some physiological and biochemical changes to withstand drought. The raffinose family of oligosaccharides ( RFO s) are sugars that have a significant role in abiotic stress tolerance. Galactinol synthase ( EC 2.4.1.123; GolS ) initiates the primary step of the RFO s synthesis. Their accumulation implies a role for RFO s in abiotic stress adaptation. The galactinol synthase gene from proso millet was isolated and characterized. Full length proso millet galactinol synthase gene of size ~1,200 bp having 3 exons with 2 introns was isolated and predicted using bioinformatics tools. A high sequence similarity was observed at 97.2, 95.6, 91.8 and 85.4% with Panicum hallii, Panicum virgatum, Setaria italica and Zea mays mRNA, respectively. PmGolS gene expression pattern with respect to drought stress was evaluated in proso millet. PmGolS gene was highly expressed, 40.3 and 23.7-fold in vegetative and reproductive stages of drought-stressed plants respectively compared to control. It suggested that PmGolS gene has an active role in drought stress tolerance.