Microbial communities inhabiting plants have emerged as crucial factors in regulating plant health and defense against disease-causing pathogens. T...

MultiSearch Tag Explorer - Search and discover topics.

Albugo infection reduces the diversity of microbial community in the phyllosphere of A. thaliana To investigate the diversity and compositional dynamics of the phyllosphere microbiome in relation to leaf infection by the obligate biotrophic pathogen Albugo (Oomycota phylum), we obtained the microbiome data from an A. thaliana collection, on which we have previously performed amplicon sequencing and described the microbiome9. Shoot samples (n = 351) were collected from six sites near Tübingen, Germany (48.52° N, 9.06° E, Fig. 1a), over six years (2014–2019). Microbiome data were obtained from epiphytic and endophytic leaf fractions using amplicon sequencing, and the host genotype was determined using whole genome sequencing (Fig. 1b)9. Here, we further analyzed endophytic microbiome due to their tight association with the host25. Since Albugo was the major pathogen in A. thaliana leaves at the time of sampling, samples were categorized as infected with observable symptoms or uninfected without observable symptoms based on the presence of characteristic white blisters on leaves (Supplementary Table 1). We first conducted diversity analysis to compare the leaf-associated microbial communities between infected and uninfected plants. Alpha diversity (within-sample diversity, measured by Shannon’s index) demonstrated that, on average, bacterial and nonfungal eukaryotic (NFEuk) communities in infected plants...

White blister is a foliar disease that may be found in the garden on a limited range of ornamentals, vegetables and weeds. It can reduce plant vigour, and sometimes also causes distorted growth.

Plant nucleotide-binding leucine-rich repeat (NLR) immune receptors typically confer resistance through recognition of specific pathogen effectors. The Arabidopsis NLR WRR4A defies this paradigm by recognizing multiple sequence-divergent effectors from Albugo candida, conferring resistance to multiple pathogen races. Despite minimal sequence similarity, these effectors share a conserved N-terminal ferredoxin-like fold. Through cryo-EM structure determination of two WRR4A resistosomes bound to sequence-distinct effectors, combined with AlphaFold modelling, we reveal a shape-based recognition mechanism: WRR4A engages structurally conserved backbone features of the effectors in a mostly side chain-independent manner, enabling recognition of diverse effectors with similar three-dimensional architectures. These insights guided successful engineering of WRR4A to acquire novel recognition specificity. In addition, analysis of the monomeric WRR4A resting state reveals a distinct domain architecture characteristic of C-JID–containing TIR-NLRs and informs their activation mechanism. This work provides insights into NLR-mediated broad-spectrum recognition and the potential for structure-informed engineering of improved crop resistance.