乙烯诱导水仙成花相关代谢物和基因的筛选与分析

Screening of Metabolites and Genes Related to Floral Formation of Chinese Narcissus Induced by Ethylene

摘要:

为了解乙烯诱导水仙（Narcissus tazetta var.chinensis）成花的生理和分子机制，利用代谢组和转录组测序技术，筛选乙烯诱导水仙成花的差异表达代谢物和基因。结果表明，乙烯处理的侧芽检测到12个差异表达代谢物（DEM），包括7个上调，5个下调，其中，（±）7-表茉莉酸、多巴胺、亚精胺可能与乙烯诱导水仙成花正相关，而吲哚及其衍生物呈负相关。转录组共获得1 021个差异表达基因（DEG），包括615个上调，406个下调，在DEG中鉴定筛选了45个与乙烯信号传导和开花相关的差异表达基因。乙烯诱导水仙成花启动可能先激活水仙鳞茎内源植物激素（尤其乙烯）信号通路的变化，与开花促进基因FPF1和MADS15的上调表达密切相关。9个基因的qRT-PCR结果验证了RNA-Seq的正确性。这些差异表达的代谢物和基因在水仙成花启动过程中可能具有重要作用。

Abstract:

In order to understand the mechanism of the narcissus (Narcissus tazetta var. chinensis) floral induction, the differentially expressed metabolites and genes were screened from the outermost buds treated with exogenous ethylene by using metabolome and transcriptome sequencing techniques. The results showed that 12 differentially expressed metabolites (DEMs) were detected, including 7 up-regulated and 5 down-regulated DEMs. Among them, (±) 7-epigenJasmonic acid, dopamine and spermidine might be positively correlated with narcissus floral induction, while indole and its derivatives were negatively correlated. A total of 1 021 differentially expressed genes (DEGs) were identified in the transcriptome, including 615 up-regulated and 406 down-regulated DEGs. Forty-five differentially expressed genes related to ethylene signal transduction and flowering were identified in the DEGs. The changes of endogenous plant hormone (especially ethylene) signaling pathway in narcissus bulbs were activated firstly by exogenous ethylene, and the floral induction of narcissus via exogenous ethylene was closely related to the up-regulated expression of FPF1 and MADS15. Nine genes correlated with flowering were verified by qRT-PCR analysis and the expression profiles were consistent with the RNA-Seq results. Therefore, these DEMs and DEGs might have vital function on the narcissus floral induction, which might play an important role in the floral formation of narcissus induced exogenous ethylene.