title: Genome-Wide Association Study of Arabidopsis thaliana Identifies Determinants of Natural Variation in Seed Oil Composition.
abstract: The renewable source of highly reduced carbon provided by plant triacylglycerols (TAGs) fills an ever increasing demand for food, biodiesel, and industrial chemicals. Each of these uses requires different compositions of fatty acid proportions in seed oils. Identifying the genes responsible for variation in seed oil composition in nature provides targets for bioengineering fatty acid proportions optimized for various industrial and nutrition goals. Here, we characterized the seed oil composition of 391 world-wide, wild accessions of Arabidopsis thaliana, and performed a genome-wide association study (GWAS) of the 9 major fatty acids in the seed oil and 4 composite measures of the fatty acids. Four to 19 regions of interest were associated with the seed oil composition traits. Thirty-four of the genes in these regions are involved in lipid metabolism or transport, with 14 specific to fatty acid synthesis or breakdown. Eight of the genes encode transcription factors. We have identified genes significantly associated with variation in fatty acid proportions that can be used as a resource across the Brassicaceae. Two-thirds of the regions identified contain candidate genes that have never been implicated in lipid metabolism and represent potential new targets for bioengineering.
authors.affiliation: From the US Vegetable Laboratory, Agricultural Research Service, United States Department of Agriculture, Charleston, SC 29414 (Branham); Department of Biology, Washington University, St. Louis, MO 63130 (Wright); Integrative Biology Department, University of Texas at Austin, Austin, TX 78712 (Branham, Reba, and Linder). sandra.branham@ars.usda.gov.
authors.forename: Sandra E
authors.initials: SE
authors.lastname: Branham
authors.affiliation: From the US Vegetable Laboratory, Agricultural Research Service, United States Department of Agriculture, Charleston, SC 29414 (Branham); Department of Biology, Washington University, St. Louis, MO 63130 (Wright); Integrative Biology Department, University of Texas at Austin, Austin, TX 78712 (Branham, Reba, and Linder).
authors.forename: Sara J
authors.initials: SJ
authors.lastname: Wright
authors.affiliation: From the US Vegetable Laboratory, Agricultural Research Service, United States Department of Agriculture, Charleston, SC 29414 (Branham); Department of Biology, Washington University, St. Louis, MO 63130 (Wright); Integrative Biology Department, University of Texas at Austin, Austin, TX 78712 (Branham, Reba, and Linder).
authors.forename: Aaron
authors.initials: A
authors.lastname: Reba
authors.affiliation: From the US Vegetable Laboratory, Agricultural Research Service, United States Department of Agriculture, Charleston, SC 29414 (Branham); Department of Biology, Washington University, St. Louis, MO 63130 (Wright); Integrative Biology Department, University of Texas at Austin, Austin, TX 78712 (Branham, Reba, and Linder).
authors.forename: C Randal
authors.initials: CR
authors.lastname: Linder
mesh_terms: D017360:Arabidopsis / Q000737:chemistry / Q000235:genetics*; D002874:Chromosome Mapping; D005227:Fatty Acids / Q000737:chemistry*; D017343:Genes, Plant; D056726:Genetic Association Studies; D050356:Lipid Metabolism; D010938:Plant Oils / Q000737:chemistry*; D020641:Polymorphism, Single Nucleotide; D012639:Seeds / Q000737:chemistry
chemical_list: D005227:Fatty Acids; D010938:Plant Oils
keywords: Arabidopsis thaliana; fatty acids; genome-wide association mapping; lipid metabolism; seed oil composition; triacylglycerol