Velvet Bean Severe Mosaic Begomovirus DNA: A Encoded RNA Silencing Suppressor Proteins
Genus Begomovirus of Geminiviridae family has widest host range in plants. It can be monopartite or bipartite. These are further grouped into old world (monopartite/bipartite) and new world (bipartite) based on their genome. In the defence and counter defence strategies of plants and viruses, the latter evolved some proteins which can suppress the RNA silencing and these viral proteins are known as RSS (RNA silencing suppressors). Number of viral proteins are identified as RSS. Mucuna pruriens commonly known as velvet bean or magic bean also owing to its medicinal properties due to which its widely used in medicines for curing diseases like Parkinson’s disease, bite of snake and in case of liver dysfunction. Velvet bean severe mosaic virus (VbSMV) infecting Mucuna pruriens has been identified. In the study suppressor proteins were identified using Agrobacterium co-infiltration assay using Nicotiana benthamiana. Three genes AV2, AV1 and AC2 showed suppressor activity, though only AV2 showed strong suppressor activity as compared to AV1 and AC2 genes.