Guangxi Subtropical Crops Research Institute
Natural Science Foundation for Distinguished Young Scholars of Guangxi(2023GXNSFBA026222); Basic Scientific Research Business Special Project of Guangxi Agricultural science(Gui Nong Ke2023YM11); Basic Scientific Research Business Special Project of Guangxi Agricultural science(Gui Nong Ke2021YT152).
为探究热带睡莲花器官不同部位的花香代谢通路及参与萜类香气物质生物合成的差异表达基因。本研究借助转录组测序技术，以热带睡莲保罗蓝为研究对象，对其花器官的花瓣(PE)、雄蕊(ST)和雌蕊(PI) 3个部位进行转录组测序分析。研究结果显示，3个部位获得的Clean Data均大于6.30Gb，Q30碱基百分比均在90.09%及以上，GC含量为48.42-50.31%。3个部位差异表达基因分析结果显示，PE-vs-PI、ST-vs-PI和ST-vs-PE的差异表达基因数目分别为7853个、7501个和2526个，前两组的差异表达基因数量相近。GO分类和富集分析显示，3个比较组的差异表达基因主要参与了生物调节、细胞过程、代谢过程和刺激应答的生物学过程；KEGG分类和富集分析显示，PE-vs-PI的差异表达基因显著富集的KEGG通路最多，其次为ST-vs-PI，ST-vs-PE最少。从3个比较组共有的794个差异表达基因中筛选出98个参与萜类物质代谢差异表达基因，富集于4条萜类物质合成通路，且PE-vs-PI和ST-vs-PI的差异基因数目均高于ST-vs-PE。已知的金合欢醛和二萜贝壳杉烯合成关键基因HMGR和DXS在花瓣和雄蕊的表达量均高于雌蕊。从98个差异表达基因随机选取了6个基因进行qRT-PCR验证，基因表达变化趋势与转录组测序一致。研究结果为热带睡莲萜类香气物质生物合成分子机制提供了科学参考。
To investigate the floral aroma metabolism pathways and differentially expressed genes involved in the biosynthesis of terpenoid aroma compounds in different parts of tropical waterlily organs. The transcriptome sequencing technique was used to analyze the petal (PE), stamen (ST) and pistil (PI) of the flower organ of N. ‘Paul Stetson’. According to the results, the Clean Data obtained from the three sites were greater than 6.30Gb, all of the Q30 base percentage was higher than 90.09% , and the GC-content was 48.42~50.31%. The analysis results of DEGs in three site samples showed that the number of differentially expressed genes in PE vs PI, ST vs PI, and ST vs PE was 7853, 7501, and 2526, respectively. The number of DEGs in the first two groups was similar. GO classification and enrichment analysis showed that the DEGs of the three comparative groups were mainly involved in biological regulation, cellular processes, metabolic processes, and stimulus response biological processes; KEGG classification and enrichment analysis showed that the KEGG pathway with significantly enriched DEGs in PE vs PI was the most abundant, followed by ST vs PI, with ST vs PE being the least. 98 DEGs involved in the terpenoid metabolism were selected from 794 DEGs in three comparative groups, which were enriched in four terpenoid floral aroma synthesis pathways, and the number of DEGs in PE vs PI and ST vs PI was higher than that in ST vs PE. In petals and stamens, the genes responsible for synthesis of acacia aldehyde and diterpenoid kaurene, were expressed at higher levels than in pistils. A total of six genes were randomly selected from 98 DEGs for qRT-PCR verification, and ttranscriptome sequencing confirmed the trend of gene expression. The results provide a scientific reference for the molecular mechanism of terpenoid aroma compounds biosynthesis in tropical waterlilies.