The potato resistance protein Rx1 can recognize Potato Virus X and iniate an efficient defense response tohat limit the virus spreading through the plant.
Little is known about the mechanism by which Rx1 activates this defense response. In this study we found that Rx1 is present in the nucleus and the cytoplasm of the plant cell and that it needs to be present both subcellular compartments for full functionality. The N-terminal coiled-coil (CC) domain is required for accumulation of Rx1 in the nucleus, whereas the leucin-rich repeat (LRR) domain promoted the localization in the cytoplasm. Our results support a model in which interdomain interactions and folding states determine the nucleo-cytoplasmic distribution of Rx1.