title: Concurrent Overexpression of Arabidopsis thaliana Cystathionine γ-Synthase and Silencing of Endogenous Methionine γ-Lyase Enhance Tuber Methionine Content in Solanum tuberosum.
abstract: Potatoes (Solanum tuberosum) are deficient in methionine, an essential amino acid in human and animal diets. Higher methionine levels increase the nutritional quality and promote the typically pleasant aroma associated with baked and fried potatoes. Several attempts have been made to elevate tuber methionine levels by genetic engineering of methionine biosynthesis and catabolism. Overexpressing Arabidopsis thaliana cystathionine γ-synthase (AtCGS) in S. tuberosum up-regulates a rate-limiting step of methionine biosynthesis and increases tuber methionine levels. Alternatively, silencing S. tuberosum methionine γ-lyase (StMGL), which causes decreased degradation of methionine into 2-ketobutyrate, also increases methionine levels. Concurrently enhancing biosynthesis and reducing degradation were predicted to provide further increases in tuber methionine content. Here we report that S. tuberosum cv. Désirée plants with AtCGS overexpression and StMGL silenced by RNA interference are morphologically normal and accumulate higher free methionine levels than either single-transgenic line.
authors.affiliation: Boyce Thompson Institute for Plant Research , 533 Tower Road, Ithaca, New York 14853, United States.
authors.forename: Pavan
authors.identifier: http://orcid.org/0000-0003-4718-3601
authors.initials: P
authors.lastname: Kumar
authors.affiliation: Boyce Thompson Institute for Plant Research , 533 Tower Road, Ithaca, New York 14853, United States.
authors.forename: Georg
authors.identifier: http://orcid.org/0000-0002-9675-934X
authors.initials: G
authors.lastname: Jander
mesh_terms: D017360:Arabidopsis / Q000201:enzymology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D019757:Carbon-Oxygen Lyases / Q000235:genetics* / Q000378:metabolism; D013437:Carbon-Sulfur Lyases / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D060847:Metabolic Engineering; D008715:Methionine / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D035281:Plant Tubers / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D011198:Solanum tuberosum / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D010940:Plant Proteins; D008715:Methionine; C022696:O-succinylhomoserine (thiol)-lyase; D019757:Carbon-Oxygen Lyases; D013437:Carbon-Sulfur Lyases; C021558:L-methionine gamma-lyase
keywords: cystathionine γ-synthase; essential amino acids; methionine; methionine γ-lyase; potato; tuber