Development of alternative Potyviridae resistance mechanisms through modification of the eIF4E translation initiation complex

Plant viruses are a large problem in crop production and can cause severe reduction in yield as well as increases in production costs when employing preventative measures such as pesticides. In addition to this they often show little or no visible symptoms. Previously at least one gene conferring broad-spectrum virus resistance to TuMV (Potyviridae) within horticultural brassica crops was identified. The gene, eIF(iso)4E, functions as part of a complex of proteins that work together in the cap recognition and binding during mRNA translation. It is thought that the Potyviridae is able to interact with this complex order to utilise the host's cellular machinery and infect the plant. It is thought that a mutated copy of the gene is able to confer resistance to the virus, as it is no longer able to recognise the viral protein bound to the viral RNA genome during cap binding. It has been shown that there are multiple copies of eIF4E as well as isoform (eIF(iso)4E) within the brassica genome, however new access to a complete genome sequence will allow for the exploration to find if more copies are present. In addition to this, double mutants of eIF(iso)4G1 and eIF(iso)4G2, which code for other proteins from this complex have also showed resistance to TuMV (Nicaise et al., 2007). This project aims to explore weather other members of the complex can confer resistance as well as to better understand the already identified genes. In addition use the information learned to create CRISPR knockouts in Brassica, conferring broad-spectrum resistance to Potyviridae.