SummaryFrom the characterization of the recessive resistance gene, sbm1, in pea we have identified the eukaryotic translation initiation factor, eIF4E, as a susceptibility factor required for infection with the Potyvirus, Pea seedborne mosaic virus. A functional analysis of the mode of action of the product of the dominant allele revealed a novel function for eIF4E in its support for virus movement from cell-to-cell, in addition to its probable support for viral RNA translation, and hence replication. Different resistance specificities in two independent pea lines were explained by different mutations in eIF4E. On the modelled structure of eIF4E the coding changes were in both cases lying in and around the structural pocket involved in binding the 5¢-m 7 G cap of eukaryotic mRNAs.Protein expression and cap-binding analysis showed that eIF4E encoded by a resistant plant could not bind to m 7 G-Sepharose, a result which may point to functional redundancy between eIF4E and the paralogous eIF(iso)4E in resistant peas. These observations, together with related findings for other potyvirus recessive resistances, provide a more complete picture of the potyvirus life cycle.

Two virus resistance loci on linkage groups II and VI have provided the only sources of natural resistance against Pea seed-borne mosaic virus (PSbMV, Potyviridae) in the important crop plant Pisum sativum L. A combination of parallel approaches was used to collate linked markers, particularly for sbm-1 resistance on linkage group VI. We have identified sequences derived from the genes for the eukaryotic translation initiation factors eIF4E and eIF(iso)4E as being very tightly linked to the resistance gene clusters on linkage groups VI and II, respectively. In particular, no recombinants between sbm-1 and eIF4E were found amongst 500 individuals of an F2 cross between the BC4 resistant line (JI1405) and its recurrent susceptible parent 'Scout'. In a different mapping population, the gene eIF(iso)4E was also shown to be linked to sbm-2 on linkage group II. A parallel cDNA-AFLP comparison of pairs of resistant and susceptible lines also identified an expressed tag marker just 0.7 cM from sbm-1. eIF4E and eIF(iso)4E have been associated with resistance to related viruses in other hosts. This correlation strengthens the use of our markers as valuable tools to assist in breeding multiple virus resistances into peas, and identifies potential targets for resistance gene identification in pea.

High-efficiency narrowband emission is always in the central role of organic optoelectronic display applications. However, the development of organic afterglow materials with sufficient color purity and high quantum efficiency for hyperafterglow is still great challenging due to the large structural relaxation and severe non-radiative decay of triplet excitons. Here we demonstrate a simple yet efficient strategy to achieve hyperafterglow emission through sensitizing and stabilizing isolated fluorescence chromophores by integrating multi-resonance fluorescence chromophores into afterglow host in a single-component copolymer. Bright multicolor hyperafterglow with maximum photoluminescent efficiencies of 88.9%, minimum full-width at half-maximums (FWHMs) of 38 nm and ultralong lifetimes of 1.64 s under ambient conditions are achieved. With this facilely designed polymer, a large-area hyperafterglow display panel was fabricated. By virtue of narrow emission band and high luminescent efficiency, the hyperafterglow presents a significant technological advance in developing highly efficient organic afterglow materials and extends the domain to new applications.