Second generation of pepino mosaic virus vectors: improved stability in tomato and a wide range of reporter genes

New PepMV vectors expressing the fluorescent proteins (FPs) GFP, DsRed and mCherry. The FPs were expressed as a CP fusion through the foot and mouth disease virus 2A catalytic peptide sequence. a Schematic representation (not to scale) of the PepMV genome and modified variants PepGFP2a, PepGFPm1, PepGFPm2, carrying the GFP gene. The nucleotides marked in red correspond to synonymous mutations introduced in the corresponding vector versions to avoid sequence duplications. b Schematic representation (not to scale) of the PepMV genome variants PepDsRed and PepmCherry carrying the DsRed and mCherry genes. RdRp: RNA dependent RNA polymerase; TGB1, TGB2 and TGB3: Triple gene block proteins 1–3; CP: Coat protein; SGP: CP subgenomic promote