Rajendra Prasad Meena1,2, Gourab Ghosh1, Harinder Vishwakarma1, Jasdeep Chatrath Padaria3,4. 1. National Institute for Plant Biotechnology, Pusa Campus, New Delhi, India. 2. PG School, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India. 3. National Institute for Plant Biotechnology, Pusa Campus, New Delhi, India. jasdeep_kaur64@yahoo.co.in. 4. PG School, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India. jasdeep_kaur64@yahoo.co.in.
Abstract
BACKGROUND: Pearl millet (Pennisetum glaucum) is an essential cereal crop, whose growth and yield are not impacted by abiotic stresses, such as drought, heat, and cold. The DREB transcription factors (TF) are some of the largest groups of TFs in plants and play varied roles in plant stress response and signal transduction. METHODS AND RESULTS: In the present study, PgDREB2A gene encoding a DREB transcription factor in pearl millet was functionally characterized in Arabidopsis. DREB2A proteins contain a conserved domain that binds toethylene responsive element binding factors. Three different T1 transgenic lines overexpressing PgDREB2A gene were identified by Southern blot. Quantitative real-time polymerase chain reaction exhibited that PgDREB2A could be induced under drought conditions. As compared with the control, PgDREB2A overexpressing transgenic Arabidopsis showed increased rate of seed germination and root growth in transgenic lines under higher concentrations of mannitol, NaCl, ABA, heat and cold stress. Additionally, PgDREB2A transgenic lines showed enhanced durability after rehydration and tolerance to drought and salt stress was augmented with increased proline and reduced MDA build-up and diminishing water loss. CONCLUSIONS: Results from this study suggested that PgDREB2A as a transcription factor may improve endurance to various abiotic stresses and can be employed for developing crops tolerant to abiotic stresses.
BACKGROUND: Pearl millet (Pennisetum glaucum) is an essential cereal crop, whose growth and yield are not impacted by abiotic stresses, such as drought, heat, and cold. The DREB transcription factors (TF) are some of the largest groups of TFs in plants and play varied roles in plant stress response and signal transduction. METHODS AND RESULTS: In the present study, PgDREB2A gene encoding a DREB transcription factor in pearl millet was functionally characterized in Arabidopsis. DREB2A proteins contain a conserved domain that binds toethylene responsive element binding factors. Three different T1 transgenic lines overexpressing PgDREB2A gene were identified by Southern blot. Quantitative real-time polymerase chain reaction exhibited that PgDREB2A could be induced under drought conditions. As compared with the control, PgDREB2A overexpressing transgenic Arabidopsis showed increased rate of seed germination and root growth in transgenic lines under higher concentrations of mannitol, NaCl, ABA, heat and cold stress. Additionally, PgDREB2A transgenic lines showed enhanced durability after rehydration and tolerance to drought and salt stress was augmented with increased proline and reduced MDA build-up and diminishing water loss. CONCLUSIONS: Results from this study suggested that PgDREB2A as a transcription factor may improve endurance to various abiotic stresses and can be employed for developing crops tolerant to abiotic stresses.