Making a friend from a foe: expressing a GroEL gene from the whitefly Bemisia tabaci in the phloem of tomato plants confers resistance to tomato yellow leaf curl virus

Abstract

Some (perhaps all) plant viruses transmitted in a circulative manner by their insect vectors avoid destruction in the haemolymph by interacting with GroEL homologues, ensuring transmission. We have previously shown that the phloem-limited begomovirus tomato yellow leaf curl virus (TYLCV) interacts in vivo and in vitro with GroEL produced by the whitefly vector Bemisia tabaci. In this study, we have exploited this phenomenon to generate transgenic tomato plants expressing the whitefly GroEL in their phloem. We postulated that following inoculation, TYLCV particles will be trapped by GroEL in the plant phloem, thereby inhibiting virus replication and movement, thereby rendering the plants resistant. A whitefly GroEL gene was cloned in an Agrobacterium vector under the control of an Arabidopsis phloem-specific promoter, which was used to transform two tomato genotypes. During three consecutive generations, plants expressing GroEL exhibited mild or no disease symptoms upon whitefly-mediated inoculation of TYLCV. In vitro assays indicated that the sap of resistant plants contained GroEL-TYLCV complexes. Infected resistant plants served as virus source for whitefly-mediated transmission as effectively as infected non-transgenic tomato. Non-transgenic susceptible tomato plants grafted on resistant GroEL-transgenic scions remained susceptible, although GroEL translocated into the grafted plant and GroEL-TYLCV complexes were detected in the grafted tissues.

Bacterial symbionts in insects or the story of communities affecting communities

“…However, it seems clear that the bacteria are likely to have significant epidemiological consequences and also effects on organisms that interact with the plant. Incidentally, there are attempts to express these proteins in transgenic plants to trap viruses and avoid pathogenesis [60,61].…”

Application of molecular antiviral compounds: novel approach for durable resistance against geminiviruses

“…In a study, it was revealed that, these GroEL expressed in the plant phloem trapped the TYLCV particles. Further, it was demonstrated that whitefly derived-GroEL expressing tomato plants have provided moderate resistance to TYLCV [2,3].…”

“…Moreover, due to equal affinity of the antiviral Endosymbiotic bacterial GroEL proteins TYLCV particles will be trapped by GroEL in the plant phloem TYLCV Tomato [2,3] Recombinant antibodies Antibody fragments corresponding to the target viral proteins hinder the necessary viral infection.…”

Transient expression of siRNA targeted against the TYLCV AV1, AC1 and AC3 genes for high resistance in tomato

“…Recent studies have introduced and expressed foreign genes that affect the infection cycle to endow plant resistance (Brunetti et al, 1997). Truncated, entire, or mutated genes of TYLCV (Bendahmane and Gronenborn, 1997;Kunik et al, 1994;Yang et al, 2004) or other foreign genes have been targeted for the viral host (Akad et al, 2007;Edelbaum et al, 2009). This approach enhances resistance to TYLCV at some extent.…”