茉莉酸信号调控薄荷腺毛发育及精油合成的分子机制研究

薄荷精油具有重要的经济价值，腺毛是精油合成的重要场所。薄荷一方面通过腺毛发育来增加精油合成的场所，另一方面通过调控合成基因来控制精油的合成，从而实现精油的积累。茉莉酸（JA）信号对植物腺毛发育和萜类合成具有重要的调控作用。申请人前期研究发现JA处理能够增加薄荷腺毛密度并提高精油含量，并且鉴定到两个受JA诱导的转录因子MhMIXTA和MhWRKY1，功能研究表明MhMIXTA转化薄荷能够增加腺毛的密度，而MhWRKY1能够增加精油的含量。因此我们推测：转录因子可能是连接JA信号和下游腺毛发育与精油合成的纽带。本研究拟开展的工作包括：筛选并验证MhMIXTA和MhWRKY1响应JA信号的上游调控因子；鉴定MhMIXTA调控的靶基因及对腺毛发育的影响；研究MhWRKY1与精油合成基因启动子的互作及对精油合成的影响。通过以上研究，探讨JA信号调控薄荷腺毛发育和精油合成的分子机制。

Essential oils of Mentha haplocalyx Briq. have important economic values and glandular trichome is an important place for the biosynthesis of essential oils. In M. haplocalyx, the development of glandular trichomes and the regulation of biosynthetic genes are the two most important factors for the accumulation of essential oils. Jasmonic acid (JA) signaling plays an important role in the regulation of plant trichome development and terpenoid biosynthesis. In the previous study, we found that JA treatment could increase the density of glandular trichome and essential oil contents in M. haplocalyx and two JA-induced transcription factor MhMIXTA and MhWRKY1, were identified. We also found that overexpression of MhMIXTA in M. haplocalyx could increase the density of trichome, while overexpression of MhWRKY1 could significantly increase the content of essential oils. Therefore, we speculate that JA signal regulates the development of glandular trichomes and affects the expression of essential oil biosynthetic genes by acting on related transcription factors, thereby regulating the accumulation of essential oil. In this study, we intend to screen and validate the upstream regulators of MhMIXTA and MhWRKY1 in response to JA signaling, dientify the target genes regulated by MhMIXTA and their effects on glandular trichome development, characterize the interaction between MhWRKY1 and promoters of biosynthetic genes and their effects on essential oil biosynthesis. Through the above studies, we hope to illustrate the molecular regulation mechanism of JA signal on the development of glandular trichome and the biosynthesis of essential oils in M. haplocalyx.