Molecular events triggered by Mungbean yellow mosaic India virus infection in blackgram (Vigna mungo (L.) hepper)

Abstract

Blackgram, one of the most nutritious legume is under constant threat of viral pathogen Mungbean yellow mosaic India virus (MYMIV) causing yield losses of 85–100%. Despite the advances in omics studies, the molecular mechanism associated with viral proliferation and counter resistance thereof, is still not thoroughly understood. The current investigation deciphered transcriptomic dynamics in MYMIV resistant (Mash114) and susceptible blackgram (KUG253) genotypes, in continuation with our previous study on tagging of MYMIV resistance. A total of 10,768 and 19,013 genes were expressed differentially in MYMIV inoculated resistant and susceptible cultivars, respectively. These differentially expressed genes (DEGs) predominantly related to defence mechanism such as protein phosphatise inhibitor, signalling receptor activity, abscisic acid binding, hydrolase activity, and glutathione transferase activity. The genes involved in photosynthesis and ribosomal genes were predominant DEGs among the disease recognition and resistance related DEGs. Beside this hormone induced defence pathway i.e., abscisic acid mediated signaling pathway was enriched by DEGs and could be the plausible mechanism for conferring resistance against MYMIV through restriction of virus by callose deposition at plasmodesmata. Here we identified the four major DEGs i.e. thaumatin like protein, serine threonine protein kinase, putative DNA (cytosine 5) – methyl transferase and chlorophyll a-b binding protein of LHCII type 1-like with putative role in disease resistance against MYMIV, seated in vicinity of previously tagged MYMIV resistance locus on chromosome 6. Chlorophyll a-b binding protein of LHCII type 1-like DEG was aiding viral proliferation in KUG253 with upregulation in susceptible and downregulation in resistant inocultated plants, as compared to its constant expression in uninoculated plants.