In Planta Interaction and Transreplication of Distinct Begomoviruses and their Associated Components

摘要

The studies described here were intended to examine the transreplication and interactions abilities of a widespread ToLCNDV, and an emerging begomovirus PeLCV associated with its cognate betasatellite TbLCuB. PeLCV, a monopartite begomovirus, has been characterized from many important crops, vegetables and weeds along with its associated TbLCuB. The DNA-B of bipartite ToLCNDV genome has been successfully transreplicated by the DNA-A of different bipartite begomoviruses, albeit with low frequency. Whether PeLCV can transreplicate DNA-B of ToLCNDV is unknown. To unravel this notion, both these viruses were inoculated to the model Nicotiana benthamiana plants in all possible combinations and the in planta existence of viral components were verified by PCR and Southern blot hybridization. The results demonstrated that PeLCV transreplicated and maintained ToLCNDV DNA-B. Whereas, ToLCNDV DNA-A could not transreplicate TbLCuB. Analyses of Rep proteins structure of ToLCNDV and PeLCV revealed a structural resemblance, whereas putative iteron-binding sequences of PeLCV were compatible with the Rep-binding iterons of ToLCNDV-B. The results suggested that PeLCV and ToLCNDV DNA-B can interact synergistically and can be disastrous under field conditions.