Journal: Molecular Plant

Article Title: The IBI1 Receptor of β-Aminobutyric Acid Interacts with VOZ Transcription Factors to Regulate Abscisic Acid Signaling and Callose-Associated Defense

doi: 10.1016/j.molp.2020.07.010

Figure Lengend Snippet: Global Transcriptome Analysis of Wild-Type Arabidopsis (Col-0) and the BABA Receptor Mutant ibi1-1 . Three-week-old plants were soil-drenched with water or BABA (10 mg/l) and challenged with conidiospores of Hyaloperonospora arabidopsidis ( Hpa ) 2 days later. Replicate shoot samples for RNA extraction and analysis of callose deposition were collected at 2 dpi. Samples for the analysis of Hpa colonization were collected at 5 dpi. (A) Quantification of the effectiveness of callose depositions in arresting Hpa colonization at the epidermal cell layer. Hpa -induced callose was analyzed in aniline blue/calcofluor-stained leaves by epifluorescence microscopy. Shown are percentages of callose-arrested and non-arrested conidiospores (see Supplemental Figure 7 for details). Different letters indicate statistically significant differences in class distribution between samples (Fisher's exact tests + FDR; p < 0.05; n = 110–130 conidiospores). (B) BABA-induced resistance (BABA-IR) against Hpa . Pathogen colonization was determined by microscopy analysis of trypan blue-stained leaves. Leaves were assigned to different Hpa colonization classes (I: no growth; II: hyphal growth; III: hyphal growth + conidiophores; IV: extensive hyphal growth + conidiophores + oospores; see Supplemental Figure 6 for details). Different letters indicate statistically significant differences in class distribution between samples (Fisher's exact tests + FDR; p < 0.05; n = 25–30 leaves). (C) Principal component analysis (PCA) of relative gene expression values (Arabidopsis Gene ST 1.1 array). Biologically replicated samples ( n = 3) from Col-0 (blue) and ibi1-1 (red) are highlighted within the same PCA plot for each of the four experimental conditions (water + mock, BABA + mock, water + Hpa , and BABA + Hpa ). (D) Numbers of differentially expressed genes (DEGs) between Col-0 and ibi1-1 under the four different (pre-)treatment conditions (linear model + FDR; q < 0.01). Red bars indicate downregulated DEGs in ibi1-1 ; green bars indicate upregulated DEGs in ibi1-1 .

Article Snippet: RNA hybridization to Arabidopsis Gene ST 1.1 arrays (median 22 probes/gene, Affymetrix, #901913) was performed at the Nottingham Arabidopsis Stock Center.

Techniques: Mutagenesis, RNA Extraction, Staining, Epifluorescence Microscopy, Microscopy, Expressing