植物激素茉莉素调控花色素苷积累、表皮毛发育、雄蕊发育、对昆虫和病原菌的抗性等重要反应。茉莉素信号分子诱导SCFCOI1复合体识别并泛素化JAZ蛋白，进而调控茉莉素反应。目前还不清楚茉莉素调控花色素苷积累和表皮毛发育的信号传导机制。本论文通过酵母双杂交筛选JAZ互作蛋白，并采用生化、生理和遗传实验研究JAZ互作蛋白介导茉莉素诱导花色素苷积累和表皮毛发育的分子机理。首先，本论文以JAZ1为诱饵筛选到转录因子GL3和MYB75。酵母双杂交实验显示JAZ蛋白与WD-repeat/bHLH/MYB复合体的bHLH组分（TT8、GL3和EGL3）和MYB组分（MYB75和GL1）存在相互作用。pull-down实验、双分子荧光互补实验和荧光素酶互补实验证实JAZ蛋白与TT8、GL3、EGL3、MYB75和GL1在植物体内相互作用。瞬时表达实验显示JAZ1影响bHLH组分与MYB组分之间的相互作用，进而抑制WD-repeat/bHLH/MYB复合体的转录活性。施加茉莉素可以解除JAZ1对其互作的抑制作用，进而恢复该复合体的转录活性。这些研究表明JAZ通过与WD-repeat/bHLH/MYB复合体的bHLH组分和MYB组分互作抑制该复合体的转录活性。然后，本论文研究了WD-repeat/bHLH/MYB复合体如何调控茉莉素诱导的花色素苷积累。研究显示TT8、GL3和EGL3功能冗余地调控茉莉素诱导的花色素苷积累。WD-repeat蛋白TTG1是茉莉素诱导花色素苷积累所必需的。TT8、GL3、EGL3和MYB75在COI1的下游正调控茉莉素诱导的花色素苷积累。MYB75超表达可以恢复coi1和JAZ1Δ3A的花色素苷积累。这些结果表明WD-repeat/bHLH/MYB复合体介导茉莉素诱导的花色素苷积累。最后，本论文研究了WD-repeat/bHLH/MYB复合体如何调控茉莉素诱导的表皮毛发育。研究发现GL3和EGL3功能冗余地介导茉莉素诱导的表皮毛形成。TTG1和MYB转录因子GL1是茉莉素诱导的表皮毛产生所必需的。GL3和EGL3在COI1的下游正调控茉莉素诱导的表皮毛形成。这些研究表明WD-repeat/bHLH/MYB复合体介导茉莉素诱导的表皮毛发育。本论文揭示了茉莉素调控拟南芥花色素苷积累和表皮毛发育的信号传导机制。该研究有重要的科学意义和应用价值。关键词：茉莉素；花色素苷；表皮毛；JAZ；WD-repeat/bHLH/MYB

Jasmonic acid and its cyclopentanone derivatives are collectively known as Jasmonates (JAs). The plant hormone JA regulates anthocyanin accumulation, trichome initiation, stamen development, root growth, and defense to insect attack and pathogen infection, thereby assisting plant to grow and survive. Bioactive JA induces SCFCOI1 complex to recognize and ubiquitinate Jasmonate ZIM-domain (JAZ) proteins, then the ubiquitinated JAZ proteins will be degraded through the 26S proteasome. However, little is known about the signal transduction mechanism for JA in regulating anthocyanin accumulation and trichome initiation. In the thesis, we performed yeast two-hybrid (Y2H) screening to identify JAZ-interaction proteins, and designed biochemical, physiological and genetic experiments to explore their roles in mediating JA-regulated anthocyanin accumulation and trichome initiation.bHLH transcription factor GL3 and R2R3 MYB transcription factor MYB75 were identified to interact with JAZ1 in the Y2H screening. Further Y2H analysis showed that JAZ proteins interact with bHLH components (TT8, GL3 and EGL3) and MYB components (MYB75 and GL1) of the WD-repeat/bHLH/MYB complex. Pull-down assays, bimolecular fluorescence complementation (BiFC) assays and luciferase complementation imaging (LCI) assays displayed that JAZ proteins interact with TT8, GL3, EGL3, MYB75 and GL1 in planta. BiFC assays demonstrated that JAZ1 can affect the interaction of bHLH transcription factors (GL3 or TT8) with MYB transcription factors (GL1 or MYB75), and repress the transcriptional function of the WD-repeat/bHLH/MYB complex. Application of coronatine, a JA mimic, can deplete the JAZ1 repression on interaction of bHLH transcription factors (GL3 or TT8) with MYB transcription factors (GL1 or MYB75), and rescue the transcriptional activity of the WD-repeat/bHLH/MYB complex.Physiological and genetic studies showed that TT8, GL3 and EGL3 function redundantly to regulate JA-induced anthocyanin accumulation. WD-repeat protein TTG1 is also indispensable for JA-induced anthocyanin accumulation. TT8, GL3, EGL3 and MYB75 act downstream of COI1 to positively regulate JA-induced anthocyanin accumulation. Together with the biochemical evidence, we concluded that JAZ proteins interact with the WD-repeat/bHLH/MYB complex to positively mediate JA-induced anthocyanin accumulation.Genetic and developmental studies demonstrated that GL3 and EGL3 function redundantly to mediate JA-induced trichome initiation. WD-repeat protein TTG1 and MYB factor GL1 are essential for JA-induced trichome initiation. GL3 and EGL3 act downstream of COI1 to positive regulate JA-induced trichome initiation. Together with the biochemical results, we concluded that JAZ proteins interact with the WD-repeat/bHLH/MYB complex to mediate JA-induced trichome initiation.Key words: Jasmonates; anthocyanin; trichome; JAZ; WD-repeat/bHLH/MYB