Investigations into the localization and function of Sr35, a wheat CC-NBS-LRR protein that confers resistance to race TTKSK (Ug99) of Puccinia graminis f. sp. tritici
S. BOLUS (1), G. Coaker (1), J. Dubcovsky (1) (1) University of California, Davis, U.S.A.

Wheat stem rust is caused by the obligate fungal pathogen Puccinia graminis f. sp. tritici. Since 1999, TTKSK (Ug99) and related races of wheat stem rust have threatened global food security. Among the few genes conferring resistance to these new virulent races, Sr35 encodes a typical CC-NBS-LRR protein. We characterized Sr35 in the model plant Nicotiana benthamiana. Overexpression of Sr35 in N. benthamiana triggers cell death. However, placement of a GFP fluorescent tag on the N-terminus eliminates the ability of Sr35 to trigger cell death in N. benthamiana suggesting that the N-terminus is critical for signaling.  Nonetheless, overexpression of the CC domain alone was not sufficient to trigger cell death, a result that differs from MLA10 in barley. Results will be presented on Sr35's subcellular localization in both the signaling active and inactive constructs. Future research will focus on identifying Sr35 signaling components in wheat.

Abstract Number: P17-497
Session Type: Poster