Interactions of Arabidopsis SRFR1, a negative regulator of effector-triggered immunity, with transcription factors and transcriptional co-repressors
C. GARNER (1), C. Rogan (2), S. Kim (1), S. Bhattacharjee (3) (1) University of Missouri, U.S.A.; (2) University of Missouri, U.S.A.; (3) Regional Centre for Biotechnology, India

Regulation of the plant immune system is important for controlling specificity and amplitude of responses to pathogens, and in preventing autoimmunity. Failure to control these processes can result in a reduction in fitness. In previous work, we reported that SRFR1, a negative regulator of effector-triggered immunity, interacted with several members of the TCP family of transcription factors. We also showed that a tcp8 tcp14 tcp15 triple mutant was compromised in effector-triggered immunity. Given SRFR1’s role as a negative regulator, and the susceptible phenotype of the SRFR1-interacting tcp mutants, we hypothesized that the function of the SRFR1-TCP interaction is to repress TCP mediated defense gene expression until the proper immune stimulus has been received. To test this hypothesis further we have been exploring interactions between SRFR1 and TCP with members of the TOPLESS family of co-repressors. Data indicate that in the Col-0 background a genetic interaction exists between SRFR1 and two members of the TOPLESS family, TPR2 and TPR3, demonstrated by a reduction in shoot weight and an increase in PR1 and PR2 expression in srfr1 tpr2 and srfr1 tpr2 tpr3 mutants. In addition, using bimolecular fluorescence complementation we have so far detected an interaction between TPR2 and two of the SRFR1-interacting TCPs, TCP8 and TCP14. Progress towards establishing a nuclear SRFR1 protein interaction network will be presented.

Abstract Number: P17-527
Session Type: Poster