Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2008
Publication Date: 7/1/2008
Citation: Cavatorta, J., Perez, K., Jahn, M., Gray, S.M. 2008. Molecular evolutionary analysis of resistance gene eIF4E and creation of novel resistance alleles in potato. Phytopathology. 98:S33. Interpretive Summary:
Technical Abstract: Resistance to viruses has long been an important breeding objective for researchers working with a number of different crops. As molecular techniques have identified the genes underlying virus resistance it has become increasingly apparent that the eukaryotic translation Initiation Factor 4E (eIF4E), a protein involved in recruiting RNA to the ribosomal complex, is a common resistance mechanism in a diversity of plant taxa against a number of virus families. Potato Virus Y (PVY) is the most important viral disease of potato. Resistance at the eIF4E locus has provided resistance to PVY and other Potyviruses in a number of species including potato relatives such as pepper and tomato. The work of our lab involves the transgenic expression of these resistance genes from pepper to confer virus resistance in other species. My particular area of research has involved a molecular evolution study of the eIF4E gene. By analyzing differences in the rates of synonymous and nonsynonymous amino acid substitutions I have found that several sites of the eIF4E gene are predicted to have undergone strong positive selection and that these sites correspond significantly with codons known to be involved in virus resistance. In addition, I have generated site-directed mutagenesis of the susceptible potato gene to create a potato allele predicted to confer resistance to PVY. I have tested that these novel alleles disrupt the interaction between eIF4E and viral pathogenicity determinants and I am currently expressing these modified potato alleles in potatoes to try and engineer resistance using DNA sequences obtained from within the species. The end goal of this study is to develop a virus resistance potato cultivar with improved consumer acceptance over previous cultivars that have utilized pathogen-derived resistance.