|Title||The potato Rx1 immune receptor interacting protein Ri-7 potentiates both Rx1 dependent and independent defenses against PVX|
|Author(s)||Sukarta, O.C.A.; Slootweg, E.J.; Boeren, J.A.; Roosien, J.; Pomp, H.; Bakker, J.; Smant, G.; Goverse, A.|
|Event||Wageningen Indonesia Scientific Expose (WISE) 2017, Wageningen, 2017-03-08/2017-03-09|
Laboratory of Nematology
|Publication type||Poster (scientific)|
The Rx1 immune receptor, introgressed from the wild potato cultivar Solanum andigena, confers resistance against Potato Virus X (PVX) (Bendahmane et al., 1999). However, the underlying mechanisms of Rx1-mediated resistance are not fully understood, prompting the need to identify signaling components of Rx1-immunity. In a recent Co-IP/MS-analysis, we identified Ri-7 as a candidate interactor of Rx1 in Nicotiana benthamiana. The current research aims to determine the functional role for the interaction of Ri-7 with Rx1. We hypothesize that Ri-7 forms a complex with Rx1 to regulate immunity against PVX.
To functionally characterize Ri-7, a combination of reverse genetics and advanced microscopy techniques was performed in the model plant specie Nicotiana benthamiana. This included transient overexpression and silencing assays as well as in vivo imaging by confocal laser scanning microscopy.
Interestingly, transient overexpression of Ri-7 was demonstrated to enhance both Rx1-dependant and independent defenses against PVX (as demonstrated by PVX virulence assays). Additional expression analysis by qRT-PCR indicates that Ri-7 regulates defense gene expressions upon PVX infection and resistance by Rx1. More strikingly, we demonstrate that Ri-7 could also enhance defense responses by other structurally similar immune receptors. Collectively, our data pinpoint the integral role of Ri-7 as a central hub in defense signaling.
Keywords: Plant immunity, immune receptors, Rx1, PVX
Bendahmane, A., Kanyuka, K., and Baulcombe, D.C. (1999). The Rx gene from potato controls separate virus resistance and cell death responses. Plant Cell 11, 781.