Abstract

Sri Lankan cassava mosaic virus is a begomovirus which belongs to the family Geminiviradae of plant viruses and it is one of the most important constraints to the productivity of cassava crop in India. Understanding the molecular interactions of SLCMV with the host plants and the study of genetic requirements of the virus for establishing infection in the hosts are essential for programming a successful resistance strategy. In view of this, the role of two complementary sense genes, AC2 and AC4 of SLCMV genome was analyzed by mutation. The mutational analysis revealed the involvement of AC2 protein in accumulation of viral ssDNA. When supplemented with WT AC2 protein transiently, the mutant clone could accumulate viral ssDNA which confirmed that AC2 protein functions in replication of viral DNA. Localization of WT and mutant protein was studied. The AC4 protein was found to be located to cell periphery while AC2 was localized to the nucleus. To understand the movement of SLCMV in host tissues, recombinant agroinfectious SLCMV clones expressing GFP were constructed. Susceptibility of A. thaliana to agroinfectious clones of SLCMV was exploited to understand the host genetic factors in antiviral RNA silencing against SLCMV.