title: Enhanced seed oil production in canola by conditional expression of Brassica napus LEAFY COTYLEDON1 and LEC1-LIKE in developing seeds.
abstract: The seed oil content in oilseed crops is a major selection trait to breeders. In Arabidopsis (Arabidopsis thaliana), LEAFY COTYLEDON1 (LEC1) and LEC1-LIKE (L1L) are key regulators of fatty acid biosynthesis. Overexpression of AtLEC1 and its orthologs in canola (Brassica napus), BnLEC1 and BnL1L, causes an increased fatty acid level in transgenic Arabidopsis plants, which, however, also show severe developmental abnormalities. Here, we use truncated napin A promoters, which retain the seed-specific expression pattern but with a reduced expression level, to drive the expression of BnLEC1 and BnL1L in transgenic canola. Conditional expression of BnLEC1 and BnL1L increases the seed oil content by 2% to 20% and has no detrimental effects on major agronomic traits. In the transgenic canola, expression of a subset of genes involved in fatty acid biosynthesis and glycolysis is up-regulated in developing seeds. Moreover, the BnLEC1 transgene enhances the expression of several genes involved in Suc synthesis and transport in developing seeds and the silique wall. Consistently, the accumulation of Suc and Fru is increased in developing seeds of the transgenic rapeseed, suggesting the increased carbon flux to fatty acid biosynthesis. These results demonstrate that BnLEC1 and BnL1L are reliable targets for genetic improvement of rapeseed in seed oil production.
authors.affiliation: State Key Laboratory of Plant Genomics and National Plant Gene Research Center, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Helin
authors.initials: H
authors.lastname: Tan
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Yang
authors.forename: Fengxia
authors.initials: F
authors.lastname: Zhang
authors.forename: Xiu
authors.initials: X
authors.lastname: Zheng
authors.forename: Cunmin
authors.initials: C
authors.lastname: Qu
authors.forename: Jinye
authors.initials: J
authors.lastname: Mu
authors.forename: Fuyou
authors.initials: F
authors.lastname: Fu
authors.forename: Jiana
authors.initials: J
authors.lastname: Li
authors.forename: Rongzhan
authors.initials: R
authors.lastname: Guan
authors.forename: Hongsheng
authors.initials: H
authors.lastname: Zhang
authors.forename: Guodong
authors.initials: G
authors.lastname: Wang
authors.forename: Jianru
authors.initials: J
authors.lastname: Zuo
mesh_terms: D017360:Arabidopsis / Q000235:genetics; D029688:Brassica napus / Q000254:growth & development* / Q000378:metabolism*; D029741:Brassica rapa / Q000235:genetics; D050260:Carbohydrate Metabolism; D005227:Fatty Acids / Q000032:analysis / Q000096:biosynthesis; D005229:Fatty Acids, Monounsaturated / Q000378:metabolism*; D005632:Fructose / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D005947:Glucose / Q000378:metabolism; D006019:Glycolysis / Q000235:genetics; D008027:Light; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000235:genetics; D010940:Plant Proteins / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D000074262:Rapeseed Oil; D012639:Seeds / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D013395:Sucrose / Q000378:metabolism; D019076:Transgenes / Q000235:genetics
chemical_list: D005227:Fatty Acids; D005229:Fatty Acids, Monounsaturated; D010940:Plant Proteins; D000074262:Rapeseed Oil; D005632:Fructose; D013395:Sucrose; D005947:Glucose