Key Laboratory of Resource Biology and Biotechnology in Western China (Ministry of Education), Institute of Life Science, Northwest University, Xi'an, 710069, People's Republic of China.
Mol Genet Genomics. 2013 Apr;288(3-4):131-9. doi: 10.1007/s00438-013-0736-x. Epub 2013 Mar 6.
Lotus corniculatus L. is used worldwide as a forage crop due to its abundance of secondary metabolites and its ability to grow in severe environments. Although the entire genome of L. corniculatus var. japonicus R. is being sequenced, the differences in morphology and production of secondary metabolites between these two related species have led us to investigate this variability at the genetic level, in particular the differences in flavonoid biosynthesis. Our goal is to use the resulting information to develop more valuable forage crops and medicinal materials. Here, we conducted Illumina/Solexa sequencing to profile the transcriptome of L. corniculatus. We produced 26,492,952 short reads that corresponded to 2.38 gigabytes of total nucleotides. These reads were then assembled into 45,698 unigenes, of which a large number associated with secondary metabolism were annotated. In addition, we identified 2,998 unigenes based on homology with L. japonicus transcription factors (TFs) and grouped them into 55 families. Meanwhile, a comparison of four tag-based digital gene expression libraries, built from the flowers, pods, leaves, and roots, revealed distinct patterns of spatial expression of candidate unigenes in flavonoid biosynthesis. Based on these results, we identified many key enzymes from L. corniculatus which were different from reference genes of L. japonicus, and five TFs that are potential enhancers in flavonoid biosynthesis. Our results provide initial genetics resources that will be valuable in efforts to manipulate the flavonoid metabolic pathway in plants.
莲菝葜（Lotus corniculatus L.）因其富含次生代谢产物且能在恶劣环境中生长而被全世界用作饲料作物。虽然正在对莲菝葜 var. japonicus R. 的整个基因组进行测序，但这两个相关物种在形态和次生代谢产物产生方面的差异促使我们在遗传水平上研究这种变异性，特别是在类黄酮生物合成方面的差异。我们的目标是利用由此产生的信息来开发更有价值的饲料作物和药用材料。在这里，我们进行了 Illumina/Solexa 测序以描绘莲菝葜的转录组。我们产生了 26,492,952 条短读序列，对应于 2.38 千兆碱基的总核苷酸。然后，将这些读段组装成 45,698 条非冗余基因，其中大量与次生代谢相关的基因被注释。此外，我们根据与莲菝葜转录因子（TFs）的同源性鉴定了 2,998 条非冗余基因，并将它们分为 55 个家族。同时，对来自花、荚、叶和根的四个基于标签的数字基因表达文库的比较显示，候选基因在类黄酮生物合成中的空间表达模式存在明显差异。基于这些结果，我们从莲菝葜中鉴定了许多与莲菝葜参考基因不同的关键酶，并鉴定了五个可能在类黄酮生物合成中起增强作用的 TF。我们的结果提供了初始遗传资源，将有助于在植物中操纵类黄酮代谢途径。
