Localization of eIF4E amino acids differing between virus-susceptible and virus-resistant genotypes of pepper ( Capsicum spp., pvr2 ), tomato ( Lycopersicon spp., pot1) , lettuce ( Lactuca spp., mo1 ), pea ( Pisum sativum , sbm1 ), melon ( Cucumis melo , nsv ) and barley ( Hordeum vulgare , rym ) in the predicted amino acid sequences (protein alignment of the susceptible genotypes). Black boxes indicate amino acids differing between susceptible and resistant genotypes. The two protein regions with clustering of amino acid substitutions are highlighted in pink and blue. In red are the mutations detected by TILLING in our PS population, in green, the mutations detected in the Charentais population. The conserved tryptophan residues reported to be required for cap-binding activity are underlined in the Pisum sequence .