Interaction dynamics between the potato late blight resistance protein RB and pathogen effectors
Y. LIN (1), D. Halterman (2) (1) University of Wisconsin-Madison, U.S.A.; (2) USDA, U.S.A.

In potato, great yield and economic losses are caused by potato late blight every year. Potato late blight, caused by the oomycete pathogen Phytophthora infestans, can effectively be controlled by R protein mediated durable resistance. One of the R genes, RB which was cloned from the diploid wild potato species Solanum bulbocastanum, can specifically recognize a multigene family of effectors IPI-O and contributes to resistance to most P. infestans clonal lineages. This recognition has been shown to be mediated through direct protein-protein interaction. Most IPI-O proteins (e.g. IPI-O1, IPI-O2) can trigger a resistance response in potato with RB. While an IPI-O family member, IPI-O4, is not able to elude RB detection, but can also block recognition of IPI-O1. To better understand the mechanism of recognition/suppression, we are currently studying the interaction proteomics of RB and IPI-O proteins. RB with a double tag HA-Biotin (TAP-tag) along with IPI-O1/4 with a MYC tag were transiently expressed in Nicotiana benthamiana individually or cooperatively. After immunoprecipitation (IP) of RB protein using streptavidin labeled magnetic beads, the biotin tag has been cleaved from the recombined RB-HA-Biotin protein and isolated secondarily by HA tag to increase purity. Isolated proteins are identified using mass spectrometry. Our results will be very helpful in identifying members of the RB protein complex.

Abstract Number: P17-531
Session Type: Poster