National Key Laboratory of Plant Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai, China.
Mol Plant. 2012 Jul;5(4):865-75. doi: 10.1093/mp/ssr100. Epub 2011 Dec 6.
Plant seed oil is important for human dietary consumption and industrial application. The oil trait is controlled by quantitative trait loci (QTLs), but no QTLs for fatty acid composition are known in rice, the monocot model plant. QTL analysis was performed using F(2) and F(2:3) progeny from a cross of an indica variety and a japonica variety. Gas chromatography-mass spectrometry (GC-MS) analysis revealed significant differences between parental lines in fatty acid composition of brown rice oil, and 29 associated QTLs in F(2) and/or F(2:3) populations were identified throughout the rice genome, except chromosomes 9 and 10. Eight QTLs were repeatedly identified in both populations across different environments. Five loci pleiotropically controlled different traits, contributing to complex interactions of oil with fatty acids and between fatty acids. Nine rice orthologs of Arabidopsis genes encoding key enzymes in lipid metabolism co-localized with 11 mapped QTLs. A strong QTL for oleic (18:1) and linoleic (18:2) acid were associated with a rice ortholog of a gene encoding acyl-CoA:diacylglycerol acyltransferase (DGAT), and another for palmitic acid (16:0) mapped similarly to the acyl-ACP thioesterase (FatB) gene ortholog. Our approach rapidly and efficiently identified candidate genes for mapped QTLs controlling fatty acid composition and oil concentration, providing information for improving rice grain quality by marker assisted selection.
植物种子油对人类饮食消费和工业应用都很重要。油的特性受数量性状位点（QTLs）控制，但在单子叶模式植物水稻中，还没有脂肪酸组成的 QTL 被发现。使用籼稻品种和粳稻品种的杂交 F2 和 F2:3 后代进行了 QTL 分析。气相色谱-质谱（GC-MS）分析显示，糙米油的脂肪酸组成在亲本系之间存在显著差异，在整个水稻基因组中鉴定出 29 个与 F2 和/或 F2:3 群体相关的 QTL，但第 9 和 10 号染色体除外。在不同环境下，两个群体中重复鉴定出 8 个 QTL。5 个位点在不同性状上表现出多效性，导致油与脂肪酸之间以及脂肪酸之间存在复杂的相互作用。拟南芥基因编码脂质代谢关键酶的 9 个水稻同源基因与 11 个定位的 QTL 共定位。油酸（18:1）和亚油酸（18:2）的强 QTL 与编码酰基辅酶 A：二酰基甘油酰基转移酶（DGAT）的水稻同源基因相关，另一个与编码酰基辅酶 A：ACP 硫酯酶（FatB）基因同源的棕榈酸（16:0）的 QTL 也被类似地定位。我们的方法快速有效地鉴定了控制脂肪酸组成和油浓度的映射 QTL 的候选基因，为通过标记辅助选择提高水稻籽粒品质提供了信息。
