title: Ectopic expression of Arabidopsis Target of Rapamycin (AtTOR) improves water-use efficiency and yield potential in rice.
abstract: The target of Rapamycin (TOR) present in all eukaryotes is a multifunctional protein, regulating growth, development, protein translation, ribosome biogenesis, nutrient, and energy signaling. In the present study, ectopic expression of TOR gene of Arabidopsis thaliana in a widely cultivated indica rice resulted in enhanced plant growth under water-limiting conditions conferring agronomically important water-use efficiency (WUE) trait. The AtTOR high expression lines of rice exhibited profuse tillering, increased panicle length, increased plant height, high photosynthetic efficiency, chlorophyll content and low ∆13C. Δ13C, which is inversely related to high WUE, was as low as 17‰ in two AtTOR high expression lines. These lines were also insensitive to the ABA-mediated inhibition of seed germination. The significant upregulation of 15 stress-specific genes in high expression lines indicates their contribution to abiotic stress tolerance. The constitutive expression of AtTOR is also associated with significant transcriptional upregulation of putative TOR complex-1 components, OsRaptor and OsLST8. Glucose-mediated transcriptional activation of AtTOR gene enhanced lateral root formation. Taken together, our findings indicate that TOR, in addition to its multiple cellular functions, also plays an important role in response to abiotic stress and potentially enhances WUE and yield related attributes.
authors.affiliation: Department of Plant Sciences, University of Hyderabad, Hyderabad-500046, India.
authors.forename: Achala
authors.initials: A
authors.lastname: Bakshi
authors.affiliation: Department of Plant Sciences, University of Hyderabad, Hyderabad-500046, India.
authors.forename: Mazahar
authors.initials: M
authors.lastname: Moin
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences-GKVK, Hebbal, Bangalore, India.
authors.forename: M Udaya
authors.initials: MU
authors.lastname: Kumar
authors.affiliation: Department of Animal Biology, University of Hyderabad, Hyderabad-500046, India.
authors.forename: Aramati Bindu Madhava
authors.initials: AB
authors.lastname: Reddy
authors.affiliation: Plant Biotechnology Institute, National Research Council of Canada, Saskatoon, Saskatchewan, S7N 0W9, Canada.
authors.forename: Maozhi
authors.initials: M
authors.lastname: Ren
authors.affiliation: Biotechnology research Institute, Chinese academy of Agricultural Sciences, Beijing, P.R. China; School of Life Sciences, Chongqing University, Chongqing, P.R. China.
authors.forename: Raju
authors.initials: R
authors.lastname: Datla
authors.affiliation: Institute of Agricultural Biotechnology, PJTS Agricultural University, Rajendranagar, Hyderabad-500030, India.
authors.forename: E A
authors.initials: EA
authors.lastname: Siddiq
authors.affiliation: Department of Plant Sciences, University of Hyderabad, Hyderabad-500046, India.
authors.forename: P B
authors.initials: PB
authors.lastname: Kirti
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D000066630:Ectopic Gene Expression; D018506:Gene Expression Regulation, Plant; D012275:Oryza / Q000235:genetics / Q000254:growth & development*; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified / Q000254:growth & development; D040641:Quantitative Trait Loci; D000076223:Regulatory-Associated Protein of mTOR / Q000235:genetics; D013312:Stress, Physiological; D015854:Up-Regulation; D014867:Water; D000076242:mTOR Associated Protein, LST8 Homolog / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D019869:Phosphatidylinositol 3-Kinases; D010940:Plant Proteins; D000076223:Regulatory-Associated Protein of mTOR; D014867:Water; D000076242:mTOR Associated Protein, LST8 Homolog; C512171:TOR protein, Arabidopsis