Xu Qiufang, Ni Haiping, Zhang Jinfeng, Lan Ying, Ren Chunmei, Zhou Yijun
Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, China; Scientific Observation and Experimental Station of Crop Pests in Nanjing, Ministry of Agriculture, Nanjing 210014, China.
Institute of Plant Protection, Jiangsu Academy of Agricultural Science, Nanjing 210014, China; College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
Gene. 2015 Nov 10;572(2):169-74. doi: 10.1016/j.gene.2015.07.008. Epub 2015 Jul 3.
Rice black-streaked dwarf virus (RBSDV) can infect a number of gramineous plants and cause severe crop yield losses in southeast Asian countries. The virus is transmitted by small brown planthopper (SBPH) in a persistent circulative manner. The interactions between RBSDV and its different hosts remain unknown. Besides, how the virus adjusts itself to infect different hosts is unclear. In the present study, the relative RNA levels of the thirteen RBSDV genes in rice, maize, wheat, and SBPH were measured by real-time quantitative PCR. P7-1 and P10 genes were predominantly expressed whereas P8 and P7-2 genes were expressed at low levels in plant hosts. Similar to the expression in rice, P7-1 was the most abundantly expressed gene and P8 was expressed at the lowest level in SBPH, indicating that RBSDV adopts the same strategy to infect distinct hosts. The high expression levels of the P7-1 gene in both plants and insect suggest that it can be used as the target gene for disease diagnostics. However, the expression levels of some genes varied from host to host. P5-1, P6 and P9-1, the components of the RBSDV viroplasm, are differentially expressed in different hosts. Moreover, western blot analysis showed that the quantity of the P9-1 protein was more abundant in SBPH than in plant hosts. These data indicate that the virus may adjust its own gene expression to replicate in different hosts. Analysis of time course of gene expression revealed that P7-1 stands out as the only gene highly expressed at the earliest time point and its expression precedes all others throughout infection from 8 to 24days post-inoculation. The high expression levels of the P7-1 gene suggest that it plays a significant role in RBSDV-host interactions.
水稻黑条矮缩病毒（RBSDV）可感染多种禾本科植物，并在东南亚国家导致严重的作物产量损失。该病毒由灰飞虱以持久循环的方式传播。RBSDV与其不同宿主之间的相互作用尚不清楚。此外，病毒如何自我调节以感染不同宿主也不明确。在本研究中，通过实时定量PCR测定了水稻、玉米、小麦和灰飞虱中13个RBSDV基因的相对RNA水平。P7-1和P10基因在植物宿主中主要表达，而P8和P7-2基因表达水平较低。与在水稻中的表达相似，P7-1是在灰飞虱中表达量最高的基因，P8表达量最低，这表明RBSDV采用相同的策略感染不同宿主。P7-1基因在植物和昆虫中均高表达，表明它可作为疾病诊断的靶基因。然而，一些基因的表达水平因宿主而异。RBSDV病毒质的组成成分P5-1、P6和P9-1在不同宿主中差异表达。此外，蛋白质免疫印迹分析表明，P9-1蛋白在灰飞虱中的含量比在植物宿主中更丰富。这些数据表明，病毒可能通过调节自身基因表达以在不同宿主中复制。基因表达时间进程分析表明，P7-1是唯一在最早时间点高表达的基因，其表达在接种后8至24天的整个感染过程中先于所有其他基因。P7-1基因的高表达水平表明它在RBSDV与宿主的相互作用中起重要作用。
