赤霉病菌中RNA沉默机制及其生物学功能的研究与利用

RNA沉默现象普遍存在于真菌、植物和动物等真核生物中，在抵御外源遗传因子、异染色质的形成、基因表达调控等方面发挥重要作用。目前人们对真菌RNA沉默机制的研究主要集中在粗糙脉孢霉，对其它真菌中RNA沉默机制研究很少。我们前期研究发现：小麦赤霉病菌中存在明显的RNA沉默现象，因此，本项目通过比较基因组学分析小麦赤霉病菌中RNA沉默途径，系统研究RNA沉默途径上各个元件的生物学功能及其相互关系。在此基础上，针对赤霉病菌细胞有丝分裂的多个关键基因，构建高效双链RNA（dsRNA）的沉默载体、并转入小麦中，进而筛选高抗赤霉病的小麦转基因材料。

RNA-silencing pathway serves as an important regulator for viral defense, transposon silencing, heterochromatin formation and gene expression in almost all eukaryotes including fungi, plants and animals. Mechanisms of RNA silencing in fungi have been mainly explored in Neurospora crassa, but information on RNA-silencing in other fungi is very limited. Our previous studies have shown that the phenomena of RNA silencing is very clear in Fusarium graminearum, the mainly causal agent of what head blight. Genome-wide search showed that F. graminearum contains nine homologous components of RNA-silencing pathways. Thus, biological functions of each component will be investigated in current study. Since the application of RNA silencing to engineer transgenic plants resistant to various insects and pathogens has led to valuable outcomes, in this study, several dsRNA silencing vectors based on several key genes involved in mitosis in F. graminearum cells will be constructed and transferred in wheat cells, then transgenic plants with highly resistant to F. graminearum will be screened and identified in this study.