Genome-wide characterization of Rice Black Streaked Dwarf Virus-responsive genes in rice

Background: Rice black streaked dwarf virus (RBSDV) is an important pathogen disease in rice and gramineous planting regions all over the world. The major phenotypes of RBSDV infected rice were dwarf with dark green leaves, which generally resulted in seriously loss of yield. The RBSDV known so far is preoperatively transmitted to rice in a persistent manner by small brown planthopper (SBPH), instead of transmitting to offspring through ovary. Results: To identify RBSDV responsive genes and to explore and clarify the molecular mechanisms involved in plant-virus interaction, digital gene expression profile (DGE) analysis was performed by high-throughput sequencing using wild-type (WT) and RBSDV infected rice leaves (IRL) as materials. A total of 165,975 and 165,940 unique tags were obtained in IRL and WT libraries, respectively. In comparison with the control, 896 differentially expressed genes (DEGs) were obtained, of which 500 DEGs were up regulated and 396 DEGs were down regulated. Functional analysis showed that DEGs mainly classified into10 groups, including metabolism, stress pathogen and defense, signal transduction, Transporter, transcription and post-transcription, cell structure and division etc. To further validate reliability and authenticity of the data, 10 DEGs were randomly picked and Real-time RT-PCR was carried out, and the expression trends of 7 genes were in line with the RNA-seq results. By searching the RBSDV related miRNA database of rice, 10 targeted genes of 6 significantly changed miRNAs were also identified in these DEGs. Conclusions: The data derived from RNA-seq were valid and credible. Through this research, a series of candidate RBSDV-responsive genes were obtained, and special signal transduction and metabolism pathways were built and pulled out in rice. This study provided further insight into the molecular mechanisms during compatible and incompatible interactions between viruses and their host plants.