title: Enhancement of α-linolenic acid content in transgenic tobacco seeds by targeting a plastidial ω-3 fatty acid desaturase (fad7) gene of Sesamum indicum to ER.
abstract: Expression of sesame plastidial FAD7 desaturase modified with the endoplasmic reticulum targeting and retention signals, enhances the α-linolenic acid accumulation in seeds of Nicotiana tabacum. In plants, plastidial ω-3 fatty acid desaturase-7 (FAD7) catalyzes the formation of C16 and C18 trienoic fatty acids using organellar glycerolipids and participate in the membrane lipid formation. The plastidial ω-3 desaturases (FAD7) share high sequence homology with the microsomal ω-3 desaturases (FAD3) at the amino acid level except the N-terminal organelle transit peptide. In the present study, the predicted N-terminal plastidial signal peptide of fad7 gene was replaced by the endoplasmic reticulum signal peptide and an endoplasmic reticulum retention signal was placed at the C-terminal. The expression of the modified sesame ω-3 desaturase increases the α-linolenic acid content in the range of 4.78-6.77 % in the seeds of transgenic tobacco plants with concomitant decrease in linoleic acid content. The results suggested the potential of the engineered plastidial ω-3 desaturase from sesame to influence the profile of α-linolenic acid in tobacco plant by shifting the carbon flux from linoleic acid, and thus it can be used in suitable genetic engineering strategy to increase the α-linolenic acid content in sesame and other vegetable oils.
authors.affiliation: Advanced Laboratory for Plant Genetic Engineering, Indian Institute of Technology, Kharagpur, 721302, India.|Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur, 721302, India.|Department of Biochemistry, Biophysics and Molecular Biology (BBMB), Iowa State University, Ames, IA, 50011, USA.
authors.forename: Rupam Kumar
authors.initials: RK
authors.lastname: Bhunia
authors.affiliation: Advanced Laboratory for Plant Genetic Engineering, Indian Institute of Technology, Kharagpur, 721302, India.
authors.forename: Anirban
authors.initials: A
authors.lastname: Chakraborty
authors.affiliation: Advanced Laboratory for Plant Genetic Engineering, Indian Institute of Technology, Kharagpur, 721302, India.|Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur, 721302, India.
authors.forename: Ranjeet
authors.initials: R
authors.lastname: Kaur
authors.affiliation: Advanced Laboratory for Plant Genetic Engineering, Indian Institute of Technology, Kharagpur, 721302, India.|Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur, 721302, India.|Department of Biotechnology, Indian Institute of Technology, Kharagpur, 721302, India.
authors.forename: Mrinal K
authors.initials: MK
authors.lastname: Maiti
authors.affiliation: Advanced Laboratory for Plant Genetic Engineering, Indian Institute of Technology, Kharagpur, 721302, India. rupam.micro@gmail.com.|Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur, 721302, India. rupam.micro@gmail.com.
authors.forename: Soumitra Kumar
authors.initials: SK
authors.lastname: Sen
mesh_terms: D000595:Amino Acid Sequence; D019295:Computational Biology; D004721:Endoplasmic Reticulum / Q000201:enzymology; D044943:Fatty Acid Desaturases / Q000235:genetics* / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D018087:Plastids / Q000201:enzymology; D012639:Seeds / Q000201:enzymology / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D031685:Sesamum / Q000201:enzymology* / Q000235:genetics; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism*; D017962:alpha-Linolenic Acid / Q000378:metabolism*
chemical_list: D005227:Fatty Acids; D010940:Plant Proteins; D017962:alpha-Linolenic Acid; D044943:Fatty Acid Desaturases; C078565:omega-3 fatty acid desaturase
keywords: Endoplasmic reticulum; Nicotiana tabacum; Plastid; Sesamum indicum; ω-3 Fatty acid desaturase