Molecular isolation and functional characterization of host factors required in the virus infection cycle for disease control in plants.

Abstract

Abstract Plant viral infection results in a multi-billion dollar economic loss worldwide each year. The use of genetic resistance is the most effective and sustainable approach to the control of plant viral diseases. However, owing to the lack of natural resistance genes, a single devastating viral pathogen often becomes a significant limiting factor in crop production. All plant viruses have a small viral genome that encodes a limited number of viral proteins. They must depend on host gene products (host factors) to complete their life cycle. Mutation, silencing or down-regulation of host factor gene(s) may lead to recessively inherited resistance to viruses. This is a major driving force for the molecular identification and functional characterization of host factors essential in virus infections. Potyviruses represent over 30% of all known plant viruses and constitute the largest plant virus group. Many agriculturally important viruses are potyviruses. In the last decade, several potyviral host factor genes including the well-known eIF4E or eIF(iso)4E gene have been molecularly identified. In this review, I will summarize research progress in molecular understanding of potyviral infection processes, and discuss manipulation of the identified host factors against potyviruses.