eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2017-09-25 14 3 869 880 10.13005/bbra/2520 26668 article Alok Ranjan 1,2 Kumari Archana 2 Sanjay Ranjan 3 CSIR-National Botanical Research institute, Lucknow,Uttar Pradesh-226015, India. Umea University, Umea Sweden; 901 83. Present address: Spectra Agritec, New Delhi – 110008 India. The cyclophilins genes are induced by abiotic stresses, yet their detailed function in drought and salinity remain largely unclear and need to be elaborately validated.Expression of cyclophilin was drastically induced under droughtconditions in Gossypiumherbaceum L. suggesting its stress-responsive function. In an attempt to characterize the role of G.herbacuemcyclophilingene GhCYP1, we overexpressed the GhCYP1 in tobaccousing Agrobacteriummediated transformationand explored its possible involvement in drought and salt stress tolerance.The transgenic plantsover expressing GhCYP1 exhibited tolerance against drought stress as evidenced by leaf disc assay, estimation of chlorophylland proline content along with various physiological parameters such as stomatal conductance, rate of photosynthesis and water use efficiency.The drought stressed transgenic tobaccoplants  exhibited higher proline content in leaf ( 1.84 µ mol-g fw) and root (2.02µ mol-g fw ),while a reverse trend was observed in the drought stressed wild type plants, implicating the involvement of GhCYP1 in the maintenance of physiological homeostasis. Thedetail physiological, biochemical and molecular analysis results demonstrate the implicit role of GhCYP1 in conferring multiple abiotic stress tolerance at whole-plant level. https://www.biotech-asia.org/vol14no3/gossypiumherbaceumghcyp1regulates-water-use-efficiency-and-drought-tolerance-by-modulating-stomatal-activity-and-photosynthesis-in-transgenic-tobacco/ Gossypiumherbaceum; cyclophilin; GhCYP gene; abiotic stress; proline; WUE; mannitol and NaCl stress