茉莉酸甲酯诱导葡萄悬浮细胞防卫反应机制的研究

为明确茉莉酸甲酯(methyl jasmonate,Me JA)诱导葡萄果实抗病反应的机制,以‘巨峰’葡萄悬浮细胞为试材,将其继代培养一次后分别在含10μmol·L-1 Me JA的B5培养基和含100 nmol·L-1隐地蛋白的B5培养基中(模拟病原菌接种)振荡培养15 d,每3 d测定1次细胞质量及抗病相关指标。结果显示:单一Me JA处理未激活葡萄悬浮细胞内的防卫反应;而单一隐地蛋白处理则可立即显著诱导葡萄悬浮细胞内源H2O2迸发,提升vv NPR1.1、PR1和PR2表达水平和植保素含量;经Me JA处理的葡萄悬浮细胞在添加隐地蛋白后,其细胞内出现较单一隐地蛋白处理更为显著的H2O2迸发、PR基因表达和植保素合成现象,说明经Me JA处理的悬浮细胞只在病原激发子胁迫时才表达出较强的系统抗性。因此,Me JA诱导的葡萄悬浮细胞抗病反应可归因于Priming(植物敏化过程或防御准备过程)机制。此外,经Me JA诱导的Priming反应对葡萄悬浮细胞生长无显著影响,暗示其未抑制葡萄细胞生长和胞内物质积累。

An Investigation on the Mechanism Involved in Defense Response Induced by Methyl Jasmonate in Grape Cell Suspensions

AIM: To pan the active peptides which specifically bound to the first and second extracellular membrane loops of rat CC chemokine receptor 5 (CCR5). METHODS: The technique of phage display peptide library was used and binding ability of the peptides was identified. The amino acid sequences of the first and second extracellular loops of rat CCR5 were searched in the protein database and chemically synthesized corresponding linear peptides were used as targets in the biopanning. After 3 to 4 rounds of screening with Ph.D.^TM-7 Phage Display Peptide Library were performed, the specific phages were collected and primarily identified by ELISA. RESULTS: The sequences of the peptides displayed on the selected phages were GHWKVWL and HYIDFRW, both of them exhibited positive in phage binding ELISA and the binding to phages and targets were concentration dependent and saturable. CONCLUSION: Two antagonistic active peptides specifically binding to CCR5 were successfully obtained by the technique of phage display peptide library, and the binding ability to the first and second extracellular membrane loops of rat CCR5 were proved in vitro.