Emerging role for RNA‐based regulation in plant immunity

Abstract

I.II.III.IV.V.VI.VII.References Summary Infection by phytopathogenic bacteria triggers massive changes in plant gene expression, which are thought to be mostly a result of transcriptional reprogramming. However, evidence is accumulating that plants additionally use post‐transcriptional regulation of immune‐responsive mRNAs as a strategic weapon to shape the defense‐related transcriptome. Cellular RNA‐binding proteins regulate RNA stability, splicing or mRNA export of immune‐response transcripts. In particular, mutants defective in alternative splicing of resistance genes exhibit compromised disease resistance. Furthermore, detection of bacterial pathogens induces the differential expression of small non‐coding RNAs including microRNAs that impact the host defense transcriptome. Phytopathogenic bacteria in turn have evolved effector proteins to inhibit biogenesis and/or activity of cellular microRNAs. Whereas RNA silencing has long been known as an antiviral defense response, recent findings also reveal a major role of this process in antibacterial defense. Here we review the function of RNA‐binding proteins and small RNA‐directed post‐transcriptional regulation in antibacterial defense. We mainly focus on studies that used the model system Arabidopsis thaliana and also discuss selected examples from other plants.

The Polyadenylation Factor Subunit CLEAVAGE AND POLYADENYLATION SPECIFICITY FACTOR30: A Key Factor of Programmed Cell Death and a Regulator of Immunity in Arabidopsis

“…In the context of the recent emerging role of RNAbased regulation in plant immunity, several aspects of nuclear RNA processing recently have been implicated in the response of plants to various stresses (Staiger et al, 2013). Here, we showed that oxt6 and mips1 oxt6 mutants were more susceptible than wild-type control plants to the virulent bacterium Pst.…”

Alternative Splicing at the Intersection of Biological Timing, Development, and Stress Responses

“…They serve to survey virulence factors produced by the pathogens or their action in the plant cell and accordingly trigger defense responses. Aberrant high R gene expression is associated with fitness costs for the plant, and regulation at the RNA level via AS and small interfering RNAs appears to control R transcript levels ( Figure 4) Mastrangelo et al, 2012;Staiger et al, 2013).…”

Plant defense responses against viral and bacterial pathogen infections. Focus on RNA-binding proteins (RBPs)

“…RBPs have been implicated at each level of RNA processing [4]. Cellular RNA-binding proteins perform diverse roles in cells, such as regulating RNA stability, splicing or mRNA export of immune-response transcripts [41]. Apart from the aforementioned cellular functions, RBPs are also a class of proteins which help plants to respond rapidly to environmental changes by being involved in a wide range of post-transcriptional regulatory events [48].…”

“…These reactions end up shaping the defense-related transcriptome which helps in plant defense against bacteria and viruses [41].…”