Volatiles of two growth‐inhibiting rhizobacteria commonly engage AtWRKY18 function

Abstract

SUMMARYInteractions with the (a)biotic environment play key roles in a plant's fitness and vitality. In addition to direct surface-to-surface contact, volatile chemicals can also affect the physiology of organism. Volatiles of Serratia plymuthica and Stenotrophomonas maltophilia significantly inhibited growth and induced H 2 O 2 production in Arabidopsis in dual culture. Within 1 day, transcriptional changes were observed by promoter-GUS assays using a stress-inducible W-box-containing 4xGST1 construct. Expression studies performed at 6, 12 and 24 h revealed altered transcript levels for 889 genes and 655 genes in response to Se. plymuthica or St. maltophilia volatiles, respectively. Expression of 162 genes was altered in both treatments. Meta-analysis revealed that specifically volatile-responsive genes were significantly overlapping with those affected by abiotic stress. We use the term mVAMP (microbial volatile-associated molecular pattern) to describe these volatile-specific responses. Genes responsive to both treatments were enriched for W-box motifs in their promoters, and were significantly enriched for transcription factors (ERF2, ZAT10, MYB73 and WRKY18). The susceptibility of wrky18 mutant lines to volatiles was significantly delayed, suggesting an indispensable role for WRKY18 in bacterial volatile responses.

Overexpression of an Arabidopsis cysteine-rich receptor-like protein kinase, CRK5, enhances abscisic acid sensitivity and confers drought tolerance

“…Studies in plant response to pathogens showed that WRKY60 may function through interaction with WRKY18 and WRKY40 to promote or decrease their binding affinities to the promoters of their target genes (Xu et al , 2006; Shen et al , 2007; Wenke et al , 2012). Consistently, in this study, we showed that WRKY18, WRKY40 and WRKY60 transcription factors cooperatively repress CRK5 gene expression (Figs 10–12).…”

The Arabidopsis GAGA-Binding Factor BASIC PENTACYSTEINE6 Recruits the POLYCOMB-REPRESSIVE COMPLEX1 Component LIKE HETEROCHROMATIN PROTEIN1 to GAGA DNA Motifs

“…Two replicates per genotype were used for ATH1 GeneChip (Affymetrix) analyses. Sample preparation, copy RNA synthesis, and quality controls were performed as described before (Wenke et al, 2012). The Affymetrix CEL files were imported into GeneSpring GX software version 7.3 (Agilent Technologies).…”

The Enzyme-Like Domain of Arabidopsis Nuclear β-Amylases Is Critical for DNA Sequence Recognition and Transcriptional Activation

“…Two biological replicates per genotype were grown for the microarray analyses. Sample preparation for ATH1 GeneChips was performed exactly as described previously (Wenke et al, 2012).…”