Integrating host-pathogen signaling networks during barley-powdery mildew interactions
J. ELMORE (1), P. Surana (2), W. Xu (2), M. Hunt (2), G. Fuerst (1), A. Chapman (2), M. Liu (2), D. Nettleton (2), J. Walley (2), R. Wise (1) (1) USDA-ARS/Iowa State University, U.S.A.; (2) Iowa State University, U.S.A.

Barley powdery mildew disease is caused by Blumeria graminis f. sp. hordei (Bgh). The 130-Mb Bgh genome encodes ~540 candidate secreted effector proteins (CSEPs) that are employed by the pathogen to manipulate host cell physiology during infection; the majority remain uncharacterized. RNA-sequencing was used to profile barley line CI 16151 (Mla6) and derived immune system mutants (mla6, rar3, bln1, mla6/bln1) inoculated with Bgh isolate 5874 (AVRa6) over the first 48 hours of infection. Two major waves of CSEP expression were identified: the first wave coincides with fungal penetration and the second wave occurs during establishment of haustoria. Bgh CSEP repertoires expressed at different stages of infection and within different immune system mutants are predicted to target distinct host pathways. To understand the roles of these CSEPs during infection, we have undertaken a yeast two-hybrid screen using next-generation sequencing to identify and rank potentially interacting proteins. In addition, quantitative proteomics using isobaric peptide labeling was performed to identify temporal protein networks during resistance and susceptibility signaling. We will present a multilayer network approach that integrates RNA expression, protein abundance dynamics, and protein-protein interaction data to predict critical nodes in the barley immune system. Results from this study will be used to characterize the barley proteins and pathways that control host resistance and susceptibility.

Abstract Number: C6-5, P14-425
Session Type: Concurrent