de novo转录组学分析华南地区入侵植物五爪金龙代谢特征

Metabolic Characteristics of Invasive Plant Ipomoea cairica in South China by de novo Transcriptomics

摘要:

为探究华南地区严重入侵植物五爪金龙(Ipomoea cairica)生物入侵的分子机制,对五爪金龙及其近缘种七爪金龙(I. digitata)和裂叶牵牛(I. nil)进行de novo转录组测序和组装,得到56551条unigenes,其中56522条得到注释,7815条GO注释,15615条COG注释,180201条KEGG数据库注释。转录组分析结果表明,五爪金龙氮代谢通路关键酶基因的表达高于对照。次生代谢关键酶(PAL、4CL、CAD、查耳酮合酶、苯基丙乙烯酮异构酶、槲皮黄3-O-甲基转移酶等)基因在五爪金龙与七爪金龙及裂叶牵牛中均得到协同性的差异表达,而这些代谢通路指导的产物合成对五爪金龙的抗逆境能力、生长、化感作用等均起关键作用。关键基因的RT-qPCR验证结果与转录组结果具有一致性。因此,这从分子生物学层面上对解释五爪金龙在华南地区的入侵机制提供了新的证据。

Abstract:

To explore the molecular mechanisms of Ipomoea cairica invasiveness in south China, the de novo transcriptomes from I. cairica, and two related species, I. digitata and I. nil, were sequenced and assembled. There were 56551 all-unigenes obtained by assembling the reads, among them 56522 all-unigenes were annotated, including 7815, 15615, and 180201 all-unigenes in GO, COG and KEGG databases, respectively. Moreover, the activities of NR and GS in I. cairica, key enzyme in metabolic pathway for nitrogen, were greater than those in related species. In addition, the transcriptome data showed that the genes of key enzymes in secondary metabolism, such as pal, 4cl, cad, chs, and chi, had synergic differential expression in I. cairica, I. digitata and I. nil. The production synthesis from metabolic pathway could play a key role in stress-resistant, growth and allelopathy of I. cairica. The RT-qPCR verification results of key genes were similar to those from transcriptome. Therefore, the result of the present research might explain partly the successful invasiveness of I. cairica in South China at the level of molecular biology.