Strategies for engineering virus resistance in transgenic plants

Abstract

Transgenic virus-resistant plants were first produced in 1986 by genetically engineering tobacco plants to express the coat protein of tobacco mosaic virus . The introduction of coat protein transgenes has since proved to be an extremely effective and generally applicable approach to engineering virus resistance in crop plants . Extensive field trials with transgenic, virus-resistant tobacco, tomato, potato and cucumber lines have confirmed not only the durability of the resistance under natural conditions but the ease with which virus-resistant lines retaining the original cultivar traits can be recovered .A number of alternative anti-viral strategies based on transgenes from a surprisingly wide variety of sources have also been developed . These include the use of viral genes coding for proteins involved in the replication cycle and in systemic transport of viruses within the plant, the use of interfering viral RNA sequences, and the use of transgenes derived from plant and animal sources . In the latter category, the use of mammalian antibodies to confer disease resistance in plants is a particularly exciting new development . Considerable progress has also been made towards the molecular cloning of natural anti-viral resistance genes in plants .

Advances in Agricultural Biotechnology

“…Most of the disease-resistant crops commercialized confer resistance against viruses [21]. Using gene encoding the viral coat protein of tobacco mosaic virus (TMV), the first disease-resistant plant was found, which was resistant to TMV infection [27]. Similarly, transgenic papaya conferring resistance to Papaya Ringspot Virus (PRSV) has been developed through a "pathogenderived resistance mechanism", where the 'prsv cp' gene is introduced by microparticle bombardment into papaya [28].…”

Biotechnology in the developing world: a case for increased investments in orphan crops

“…Since these reports were released, many types of sequences from both RNA and DNA plant viruses have been expressed in a diverse set of crops resulting in resistance to a wide array of pathogens (Kavanagh and Spillane, 1995;Pappu et al, 1995). More recently, scientists have turned their attention to resistance resulting from expression of genes from other sources, including mammalian antibodies (Ziegler et al, 2000), anti-viral compounds (Smirnov et al, 1997), and sequences that act to silence viral genes or silence host genes necessary for viral infection (Baulcombe, 1999;Dutilleul and Laine, 2001).…”