Genetic basis for natural variation in seed vitamin E levels in Arabidopsis thaliana
Genetic basis for natural variation in seed vitamin E levels in Arabidopsis thaliana
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DOI：
10.1073/pnas.0606221103
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发表时间：
2006-12-05
影响因子：
11.1
通讯作者：
DellaPenna, Dean
中科院分区：
文献类型：
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作者：
Gilliland, Laura U.;Magallanes-Lundback, Maria;DellaPenna, Dean
维生素E是人类必需的营养物质，主要从食物中获取，特别是从植物种子中提取的油。编码植物维生素E合成相关步骤(VTE，1-5位点)的基因已经被分离出来，并用于生育酚途径工程，取得了不同程度的成功。作为对这些方法的补充，我们对两组拟南芥重组自交系进行了数量性状基因座分析，并鉴定了14个影响种子生育酚含量和组成的QVE(定量维生素E)基因座。五个QVE间隔包含可能是QVE候选基因的VTE基因座。有9个QVE区间不包含VTE基因座，因此发现了影响种子生育酚含量和组成的新基因座。与轮回亲本相比，几个含有维生素E水平增加的加入的近等基因系显著地提高了生育酚水平。精细定位已经将QVE7(一种生育酚数量性状基因座)缩小到包含两个基因的8.5kb区间。了解拟南芥QVE基因座的基础有助于深入了解维生素E在植物中的调节和/或代谢，并对通过分子标记辅助选择和代谢工程提高作物的营养含量具有明显的指导意义。
Vitamin E is an essential nutrient for humans and is obtained primarily from food, especially oil, derived from the seed of plants. Genes encoding the committed steps in vitamin E synthesis in plants (VTE, loci 1-5) have been isolated and used for tocopherol pathway engineering with various degrees of success. As a complement to such approaches we have used quantitative trait loci analysis with two sets of Arabidopsis thaliana recombinant inbred lines and have identified 14 QVE (quantitative vitamin E) loci affecting tocopherol content and composition in seeds. Five QVE intervals contain VTE loci that are likely QVE gene candidates. Nine QVE intervals do not contain VTE loci and therefore identify novel loci affecting seed tocopherol content and composition. Several near-isogenic lines containing introgressions of the accession with increased vitamin E levels were shown to confer significantly elevated tocopherol levels compared with the recurrent parent. Fine-mapping has narrowed QVE7 (a gamma-tocopherol quantitative trait loci) to an 8.5-kb interval encompassing two genes. Understanding the basis of the QVE loci in Arabidopsis promises to provide insight into the regulation and/or metabolism of vitamin E in plants and has clear ramifications for improving the nutritional content of crops through marker-assisted selection and metabolic engineering.