[WRKY33A positively regulates disease resistance in soybean ()].

The WRKY transcription factor gene family is a plant-specific transcription factor that plays important roles defense responses. Studies in model plant demonstrated that WRKYs function downstream of mitogen activated-protein kinase (MAPK) signaling cascade and participate in defense responses through activating the expression of defense-related genes. However, the roles of WRKYs in defense responses have not been previously investigated in paleopolyploidy soybean.

[Silencing genes leads to reduced disease resistance in soybean].

The WRKYs are a group of plant-specific transcription factors that play important roles in defense responses. In this study, we silenced 2 homologous genes using a bean pod mosaic virus (BPMV) vector carrying a single fragment from the conserved region of the genes. Silencing did not result in morphological changes.

Soybean SAUL1, a Bona Fide U-Box E3 Ligase, Negatively Regulates Immunity Likely through Repressing the Activation of MPK3.

E3 ubiquitin ligases play important roles in plant immunity, but their role in soybean has not been investigated previously. Here, we used (BPMV)-mediated virus-induced gene silencing (VIGS) to investigate the function of SAUL1 (Senescence-Associated E3 Ubiquitin Ligase 1) homologs in soybean. When two closely related homologs were silenced simultaneously, the soybean plants displayed autoimmune phenotypes, which were significantly alleviated by high temperature, suggesting that SAUL1a/1b might be guarded by an R protein.

Silencing in Soybean Results in Activated Defense Responses.

Receptor-like kinases (RLKs) are a large group of pattern recognition receptors (PRRs) and play a critical role in recognizing pathogens, transducing defense signals, and mediating the activation of immune defense responses. Although extensively studied in the model plant Arabidopsis, studies of RLKs in crops, including soybean, are limited. When a () homolog (referred to as hereafter) was silenced by the BPMV ()-induced gene silencing (BPMV-VIGS), it resulted in phenotypes that were reminiscent of constitutively activated defense responses, including a significantly stunted stature with observable cell death on the leaves of the silenced plants.

Silencing GmFLS2 enhances the susceptibility of soybean to bacterial pathogen through attenuating the activation of GmMAPK signaling pathway.

The plasma membrane (PM)-localized receptor-like kinases (RLKs) play important roles in pathogen defense. One of the first cloned RLKs is the Arabidopsis receptor kinase FLAGELLIN SENSING 2 (FLS2), which specifically recognizes a conserved 22 amino acid N-terminal sequence of Pseudomonas syringae pv．tomato DC3000 (Pst) flagellin protein (flg22). Although extensively studied in Arabidopsis, the functions of RLKs in crop plants remain largely uninvestigated.

Heterotrimeric G protein signaling in plant immunity.

In animals, heterotrimeric guanine nucleotide-binding proteins (G proteins) transduce signals perceived by numerous G protein-coupled receptors (GPCRs). However, no canonical GPCRs with guanine nucleotide exchange factor (GEF) activity are present in plant genomes. Accumulated evidence indicates that, instead of GPCRs, the receptor-like kinases (RLKs) function upstream of G proteins in plants.