Starting points
In the never ending battle between plant and herbivory insects researchers search for ways to make plants less attractive. Like Dutch researchers show, this starts with the analysis of how insects manages to dodge the plant defence systems.
Herbivory insects excrete with their saliva proteins that slow down the plant defence reaction. Just enough so it does not bother them any longer. Doing so they need to bind to specific plant proteins, and disrupt their working. When it is known which plant proteins this are, then a plant breeder can ensure that the interaction can no longer take place.
This got the researchers to study which saliva proteins of the abundant whitefly bind to proteins of tomato plants. They found these saliva proteins in the food of the insects. Four of the identified proteins the researchers decided to further analyse further. One of those, G4, strongly reduced the defence response of the plant.
Identifying the binding partners of G4 gives plant breeders the starting points to create whitefly resistant plants
The big question was now: how does G4 this? To discover how the researchers studied which plant proteins bind to G4. First they went in search of candidate proteins, using a yeast screening assay. With the used assay yeast cells stay alive when G4 binds to the plant proteins. The final result: six candidate proteins.
This was followed by a check-up if these candidates also bind to G4 in plants. Two candidates actually did this. Moreover, microscope analysis showed that the two left over candidate proteins and G4 locate at the same locations in the cell. G4 appears to influence plant defence by binding to these two plant proteins.
But is a plant whitefly resistant in the absence of these proteins? To answer this question the researchers created plants without one of the candidate proteins. Surprisingly it turned out that this plant attract actually more whiteflies. But only to feed on, they were not laying eggs.
This study is giving plant breeders new starting points in their challenge of making plants whitefly resistant. Although, some more research into why G4 is binding specifically to those candidates and why these candidates are needed for plant defence is still needed.
Literature
Naalden D, Dermauw W, Ilias A, Baggerman G, Mastop M, Silven J, van Kleeff PJM, Dangol S, Gaertner NF, Roseboom W, Kwaaitaal M, Kramer G, van der Burg H, Vontas J, Van Leeuwen T, Kant M, Schuurink R. (2023) Interaction of whitefly effector G4 with tomato proteins impacts whitefly performance. Mol Plant Microbe Interact. https://doi.org/10.1094/MPMI-04-23-0045-R
Plant en Zo 