Whitefly effector G4 interacts with tomato proteins of which MIPDB141 affects whitefly performance

Abstract

AbstractThe phloem-feeding insectBemisia tabaciis an important pest, responsible for the transmission of several crop-threatening virus species. While feeding, the insect secretes a cocktail of effectors to modulate defense responses. Here, we present a set of proteins that was identified in artificial diet on whichB. tabaciwas salivating. We studied whether these candidate effectors can play a role in plant immune suppression. Effector G4 was the most robust suppressor of the flg22-induced ROS response when transiently expressed inNicotiana benthamiana. In addition, G4 was able to supress ROS inSolanum lycopersicum(tomato) andCapsicum annuum(pepper). Fused to a fluorescence tag, G4 localized in the cytoplasm inN. benthamiana. A yeast two-hybrid screen combined with a luciferase bimolecular complementation and co-localization assays resulted in the identification of two target proteins in tomato: REF-like stress related protein 1 (RSP1) and meloidogyne-induced giant cell protein DB141 (MIPDB141). Silencing ofMIPDB141in tomato, using virus-induced gene silencing, reduced whitefly fecundity up to 40% demonstrating that the protein is involved in susceptibility toB. tabaci. Together our data demonstrate that effector G4 impairs tomato immunity to whiteflies by interfering with the ROS production and via a direct interaction with tomato susceptibility protein MIPDB141.