从生存和营养的角度来看,植物的初级代谢产物非常重要。然而,油料作物中主要代谢产物的遗传基础仍不清楚。作为主要的油料作物之一,芝麻(SesamumindicumL.)是研究植物油脂代谢的潜在模型植物。因此,这项研究的目的是揭示与芝麻中初级代谢产物含量变化相关的遗传变异。我们使用气相色谱-质谱法对412种不同芝麻品种的主要代谢物进行了全面的代谢组学分析,并鉴定了总共45种代谢物,包括脂肪酸,单酰基甘油(MAGs),和氨基酸。全基因组关联研究揭示了433个与芝麻中主要代谢产物含量变化相关的重要单核苷酸多态性位点。通过整合不同的基因组分析,我们确定了MAG变异的10个关键候选致病基因,脂肪酸,天冬酰胺,和蔗糖含量。其中,SiDSEL与多个性状显著相关。SiCAC3和SiKASI与油酸和亚油酸含量的变化密切相关。SiCAC3、SiKASI、转基因拟南芥和酿酒酵母中的SiLTPI.25和SiLTPI.26表明SiCAC3是改善作物中不饱和脂肪酸水平的潜在靶基因。此外,我们发现,在芝麻中同时繁殖几种品质性状是可能的。我们的研究结果为提高芝麻种子质量和我们对油料作物初级代谢的理解提供了宝贵的遗传资源。
Plants\' primary metabolites are of great importance from the survival and nutritional perspectives. However, the genetic bases underlying the profiles of primary metabolites in oilseed crops remain largely unclear. As one of the main oilseed crops, sesame (Sesamum indicum L.) is a potential model plant for investigating oil metabolism in plants. Therefore, the objective of this
study is to disclose the genetic variants associated with variation in the content of primary metabolites in sesame. We performed a comprehensive metabolomics analysis of primary metabolites in 412 diverse sesame accessions using gas chromatography-mass spectrometry and identified a total of 45 metabolites, including fatty acids, monoacylglycerols (MAGs), and amino acids. Genome-wide association
study unveiled 433 significant single-nucleotide polymorphism loci associated with variation in primary metabolite contents in sesame. By integrating diverse genomic analyses, we identified 10 key candidate causative genes of variation in MAG, fatty acid, asparagine, and sucrose contents. Among them, SiDSEL was significantly associated with multiple traits. SiCAC3 and SiKASI were strongly associated with variation in oleic acid and linoleic acid contents. Overexpression of SiCAC3, SiKASI, SiLTPI.25, and SiLTPI.26 in transgenic Arabidopsis and Saccharomyces cerevisiae revealed that SiCAC3 is a potential target gene for improvement of unsaturated fatty acid levels in crops. Furthermore, we found that it may be possible to breed several quality traits in sesame simultaneously. Our results provide valuable genetic resources for improving sesame seed quality and our understanding of oilseed crops\' primary metabolism.