DcVgR参与柑橘黄龙病菌提高柑橘木虱生殖力的分子机制

柑橘黄龙病是由韧皮部杆菌属细菌引起的一种毁灭性柑橘病害。柑橘木虱作为柑橘黄龙病的主要传播媒介，其强大的生殖力是黄龙病在田间快速流行和爆发的重要原因。我们前期研究发现带菌柑橘木虱卵巢发育提前，其卵黄原蛋白受体基因DcVgR在卵巢内的表达显著上调，柑橘黄龙病菌是通过什么途径引起DcVgR基因的上调进而调控柑橘木虱的生殖？其分子机制尚不明确。本项目从黄龙病菌提高柑橘木虱生殖力这一现象为切入点，采用FISH、qRT-PCR、Western blot、RNAi、miRNA测序等方法：①研究黄龙病菌在柑橘木虱卵巢中的分布动态及对卵巢发育的影响；②明确DcVgR基因的表达模式及在黄龙病菌调控柑橘木虱生殖中的作用；③从转录水平和转录后水平探索DcVgR参与黄龙病菌提高柑橘木虱生殖力的分子机制。本研究力求在理论上更好地理解媒介昆虫-植物病原物间的互作关系，在实践上为柑橘木虱和柑橘黄龙病的有效防控提供新思路。

Citrus Huanglongbing (HLB) is a devastating disease of citrus which caused by citrus greening disease pathogen, Candidatus Liberibacter asiaticus (Las). Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the mainly transmitting vector of HLB. The powerful fecundity of D. citri is the important factor for the rapid spread and outbreak of HLB in the field. Our previous studies found that the ovary of Las-positive D. citri developed earlier, and the expression level of vitellogenin receptor (DcVgR) gene was also significantly up-regulated in the ovary. How does Las improve DcVgR expression and then regulate the fecundity of D. citri? The molecular mechanism underlying is still unclear. In the present study, considering fecundity improvement of D. citri by Las as breakthrough point, we are going to use FISH, qRT-PCR, Western blot, RNAi, miRNA sequencing and other methods to ① investigate Las distribution dynamics in the ovary and the effect of Las on the ovary development of D. citri; ② analyze the expression patterns of DcVgR and the function of DcVgR in the fecundity improvement of D. citri mediated by Las; ③ explore the molecular mechanisms that DcVgR involved in the regulation of Las on D. citri reproduction at the transcriptional level and post-transcriptional level. The results of this study could not only help to understand the interaction of vector insect-plant bacterium in theory, but also provide a new idea for controlling D. citri and HLB in practice.