RRS1 and infection: For the clarity of this report, we refer to RRS1-R (Ws-2), the allele conferring PopP2 recognition, as RRS1. Importantly, as a result of the conservation of immune signaling in plants, transgenic tomato expressing RPS4 and RRS1 from Arabidopsis are resistant to infection by R. solanacearum RS1002 strain that carries popP2 (Narusaka et al., 2013).