Host factors required for plant susceptibility to viruses: targets to improve plant resistance to viruses

• Published in: 2010; EMBO WORKSHOP 2010, Fenestrelle, ITA, 2010-06-12-2010-06-16, 1 p
• Main Authors: Caranta, Carole, Ouibrahim, Laurence, Lacombe, Séverine, Robaglia, Christophe, Gallois, Jean-Luc
• Format: Conference Proceeding
• Language: English
• Published: 2010
• Subjects: Agricultural sciences; cycle infectieux; cycle viral; gène de résistance; interaction plante virus; pathologie végétale; protéine virale; résistance des plantes aux virus; Sciences agricoles; sensibilité des plantes; virologie végétale; virus; virus à arn

Because of their small genome encoding generally less thari a dozen proteins the viralinfectious cycle completely relies on the use of cellular factors. The completion of theviral cycle is therefore the result of a complex interplay between virus-encoded andhost-encoded factors. ln this scheme, absence or mis-adequacy of a single host factor(also called susceptibility factors) led to plants fully or partially resistant to viruses. lnthe plant natural diversity, these non-functional versions of host factors required for theviral cycle were demonstrated to correspond to recessive resistance genes. ln recentyear, one of the results that has enabled plant virology to make a step forward is theidentification of components of the translation initiation complex as essential hostfactors required for RNA virus infection. Although translation initiation factors weredemonstrated to be highly conserved determinants of plant resistance to viruses, severaldata indicate that the molecular basis underlying translation initiation factors-mediatedresistance are highly variable. ln parallel, several recessive resistance genes againstviruses were identified and demonstrated to be distinct from translation initiationfactors. These genes are therefore very good candidates for the discovery of newsusceptibility factors. Recent results on (i) the specificity in the use of translationinitiation factors by RNA viruses and on (ii) the identification of new host susceptibilityfactors, will illustrate this to ic.