Genetic Dissecting Innate Immune Signaling Networks in Arabidopsis

Abstract

The plant innate immune system is built on a great number of processes, many of which are uncharacterized, or incompletely identified. Infection of Arabidopsis thaliana with bac- terium Pseudomonas syringae pv. tomato DC3000 carrying effector proteins AvrRpm1 and AvrRpt2, is known to elicit effector-triggered immune response (ETI) via interaction with host-cell receptor proteins RPM1 and RPS2, respectively. Recognition of pathogen- associated molecular patterns (PAMPs), and pathogen effector proteins initiate a variety of biochemical signaling events ultimately resulting in physiological changes favoring the host’s self-preservation. To better characterize those signaling pathways, we examined in- duced expression levels of immune gene transcription factor (TF) WRKY46 in mutagenized transgenic pWRKY46-LUC (WRKY46 TF fused with luciferase reporter) A. thaliana model organisms. Here, we show that the WRKY46 TF is induced by inoculation and putative subsequent elicitation of PTI and/or ETI within mutagenized plants by unknown mech- anisms. Genetic dissection of the pathways leading to such responses will permit future characterization of the underlying mechanisms and sequencing of the associated host genes.