Comparative transcriptome profiling of a resistant vs. susceptible Vigna mungo cultivar in response to Mungbean yellow mosaic India virus infection reveals new insight into MYMIV resistance

Mungbean yellow mosaic India virus (MYMIV), causal agent of the yellow mosaic disease (YMD) in leguminous crops, causes enormous fall in productivity of economically important legumes worldwide. Vigna mungo is severely affected by YMD. In this study, the transcriptional modifications in V. mungo during MYMIV resistance as well as susceptibility were studied and 145 and 109 differentially expressed transcripts were identified in resistant and susceptible plants, respectively through suppression subtractive hybridization. Selected transcripts were validated through RT-qPCR. In incompatible interaction, significant induced expression of genes present in jasmonic acid signalling pathway was observed. Moreover, in incompatible interaction the generation of physical barrier upon virus invasion and maintenance of reactive oxygen species homeostasis was also evidenced. In compatible interaction, the virus succeeded to manipulate the host machinery resulting in significant decrease in defense related gene expression leading to manifestation of disease symptoms. We have generated two hypothetical models of incompatible and compatible interactions based on the possible biological and molecular function of differentially expressed transcripts obtained from resistant and susceptible plants following MYMIV infection. Knowledge gained from these models will help in deciphering the mechanism of MYMIV resistance not only in V. mungo but also in other plant-pathogen interaction study.