Interaction Between Translation Initiation Factor eIF4E in Banana and the VPg Protein of Banana Bract Mosaic Virus Reveals Potential Targets for Genome Editing

Plant viruses need host factors to complete their life cycle. The eukaryotic translation initiation factor 4E (eIF4E) and its isoforms are the host factors essential for infection by plant viruses in the genus Potyvirus. The present study describes the characterization of eIF4E gene in banana cultivar Nendran, and its interaction with the viral genome-linked protein (VPg) of banana bract mosaic virus (BBrMV). The in-silico analysis of 853 bp coding mRNA region of eIF4E revealed the presence of five exons. The deduced amino acid sequence had 99.58% identity with the predicted protein sequence of the eIF4E-1 in Musa acuminata subspecies malaccensis. Expression profiling of eIF4E gene in banana cultivar Nendran using qRT-PCR revealed up to 16.9-fold up-regulation of the gene in response to BBrMV infection, indicating its role in disease development. The three-dimensional models of the eIF4E and VPg proteins were generated to deduce the precise interaction between the two proteins. Using the online server ZDOCK, ten interaction complexes were obtained. In nine out of the ten complexes, the maximum number of residues of the eIF4E interacted with the Tyrosine-63rd residue of VPg. The corresponding nucleotides were identified as the potential targets for editing the host eIF4E gene to impart potyvirus resistance.