VIGS technology: an attractive tool for functional genomics studies in legumes
Résumé
Legume species are among the most important crops worldwide. In recent years, six legume genomes have been completely sequenced, and there is now an urgent need for reverse-genetics tools to validate genes affecting yield and product quality. As most legumes are recalcitrant to stable genetic transformation, virus-induced gene silencing (VIGS) appears to be a powerful alternative technology for determining the function of unknown genes. VIGS technology is based on the property of plant viruses to trigger a defence mechanism related to post-transcriptional gene silencing (PTGS). Infection by a recombinant virus carrying a fragment of a plant target gene will induce homology-dependent silencing of the endogenous target gene. Several VIGS systems have been developed for legume species since 2004, including those based on Bean pod mottle virus, Pea early browning virus, and Apple latent spherical virus, and used in reverse-genetics studies of a wide variety of plant biological processes. In this work, we give an overview of the VIGS systems available for legumes, and present their successful applications in functional genomics studies. We also discuss the limitations of these VIGS systems and the future challenges to be faced in order to use VIGS to its full potential in legume species.