title: Enhancing the accumulation of omega-3 long chain polyunsaturated fatty acids in transgenic Arabidopsis thaliana via iterative metabolic engineering and genetic crossing.
abstract: The synthesis and accumulation of long chain polyunsaturated fatty acids such as eicosapentaenoic acid has previously been demonstrated in the seeds of transgenic plants. However, the obtained levels are relatively low, indicating the need for further studies and the better definition of the interplay between endogenous lipid synthesis and the non-native transgene-encoded activities. In this study we have systematically compared three different transgenic configurations of the biosynthetic pathway for eicosapentaenoic acid, using lipidomic profiling to identify metabolic bottlenecks. We have also used genetic crossing to stack up to ten transgenes in Arabidopsis. These studies indicate several potential approaches to optimize the accumulation of target fatty acids in transgenic plants. Our data show the unexpected channeling of heterologous C20 polyunsaturated fatty acids into minor phospholipid species, and also the apparent negative metabolic regulation of phospholipid-dependent Δ6-desaturases. Collectively, this study confirms the benefits of iterative approaches to metabolic engineering of plant lipid synthesis.
authors.affiliation: Department of Biological Chemistry, Rothamsted Research, Harpenden, Herts AL5 2JQ, UK.
authors.forename: Noemi
authors.initials: N
authors.lastname: Ruiz-López
authors.forename: Richard P
authors.initials: RP
authors.lastname: Haslam
authors.forename: Mónica
authors.initials: M
authors.lastname: Venegas-Calerón
authors.forename: Tianbi
authors.initials: T
authors.lastname: Li
authors.forename: Joerg
authors.initials: J
authors.lastname: Bauer
authors.forename: Johnathan A
authors.initials: JA
authors.lastname: Napier
authors.forename: Olga
authors.initials: O
authors.lastname: Sayanova
mesh_terms: D000214:Acyl Coenzyme A / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D016718:Arachidonic Acid / Q000096:biosynthesis; D003433:Crosses, Genetic; D015118:Eicosapentaenoic Acid / Q000096:biosynthesis; D044943:Fatty Acid Desaturases / Q000235:genetics / Q000378:metabolism*; D015525:Fatty Acids, Omega-3 / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D060847:Metabolic Engineering; D030821:Plants, Genetically Modified / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
chemical_list: D000214:Acyl Coenzyme A; D015525:Fatty Acids, Omega-3; D005231:Fatty Acids, Unsaturated; D016718:Arachidonic Acid; D015118:Eicosapentaenoic Acid; C022369:phospholipid desaturase; D044943:Fatty Acid Desaturases