title: Introgression of the SbASR-1 gene cloned from a halophyte Salicornia brachiate enhances salinity and drought endurance in transgenic groundnut (arachis hypogaea)and acts as a transcription factor [corrected].
abstract: The SbASR-1 gene, cloned from a halophyte Salicornia brachiata, encodes a plant-specific hydrophilic and stress responsive protein. The genome of S. brachiata has two paralogs of the SbASR-1 gene (2549 bp), which is comprised of a single intron of 1611 bp, the largest intron of the  abscisic acid stress ripening [ASR] gene family yet reported. In silico analysis of the 843-bp putative promoter revealed the presence of ABA, biotic stress, dehydration, phytohormone, salinity, and sugar responsive cis-regulatory motifs. The SbASR-1 protein belongs to Group 7 LEA protein family with different amino acid composition compared to their glycophytic homologs. Bipartite Nuclear Localization Signal (NLS) was found on the C-terminal end of protein and localization study confirmed that SbASR-1 is a nuclear protein. Furthermore, transgenic groundnut (Arachis hypogaea) plants over-expressing the SbASR-1 gene constitutively showed enhanced salinity and drought stress tolerance in the T1 generation. Leaves of transgenic lines exhibited higher chlorophyll and relative water contents and lower electrolyte leakage, malondialdehyde content, proline, sugars, and starch accumulation under stress treatments than wild-type (Wt) plants. Also, lower accumulation of H2O2 and O2.- radicals was detected in transgenic lines compared to Wt plants under stress conditions. Transcript expression of APX (ascorbate peroxidase) and CAT (catalase) genes were higher in Wt plants, whereas the SOD (superoxide dismutase) transcripts were higher in transgenic lines under stress. Electrophoretic mobility shift assay (EMSA) confirmed that the SbASR-1 protein binds at the consensus sequence (C/G/A)(G/T)CC(C/G)(C/G/A)(A/T). Based on results of the present study, it may be concluded that SbASR-1 enhances the salinity and drought stress tolerance in transgenic groundnut by functioning as a LEA (late embryogenesis abundant) protein and a transcription factor.
authors.affiliation: Marine Biotechnology and Ecology Division, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, Gujarat, India.
authors.forename: Vivekanand
authors.initials: V
authors.lastname: Tiwari
authors.affiliation: Marine Biotechnology and Ecology Division, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, Gujarat, India.
authors.forename: Amit Kumar
authors.initials: AK
authors.lastname: Chaturvedi
authors.affiliation: Marine Biotechnology and Ecology Division, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, Gujarat, India.
authors.forename: Avinash
authors.initials: A
authors.lastname: Mishra
authors.affiliation: Marine Biotechnology and Ecology Division, CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar, Gujarat, India.
authors.forename: Bhavanath
authors.initials: B
authors.lastname: Jha
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000595:Amino Acid Sequence; D010367:Arachis / Q000235:genetics* / Q000378:metabolism; D060387:Ascorbate Peroxidases / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D019663:Chenopodiaceae / Q000235:genetics* / Q000378:metabolism; D055864:Droughts; D004591:Electrophoresis, Polyacrylamide Gel; D018628:Gene Dosage; D018506:Gene Expression Regulation, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D020133:Reverse Transcriptase Polymerase Chain Reaction; D054712:Salinity; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors; C066246:late embryogenesis abundant protein, plant; D006861:Hydrogen Peroxide; D060387:Ascorbate Peroxidases; D002374:Catalase