Assay for transposase-accessible chromatin using sequencing (ATAC-Seq) of Barley CI 16151 and fast-neutron-derived, immune-compromised mutants infected with the powdery mildew fungus (Blumeria hordei (Bh); isolate 5874)

MLA (mildew locus a), is an immune receptor that interacts with several transcription factors (TFs), and thus, represents a model to explore regulatory architecture during defense. To characterize chromatin accessibility of barley during powdery mildew infection, a series of isogenic mutant genotypes and timepoints were subjected to ATAC sequencing.

We designed our study around two diverse genes in host immunity, mildew locus a (Mla6), a nucleotide binding leucine-rich repeat (NLR) immune receptor, and the Blufensin1 (Bln1) basal defense regulator, which influence immunity in a resistance (R)-gene dependent and R-gene independent manner, respectively. In addition to the CI 16151 resistant progenitor (Mla6, Bln1), three mutants were utilized: the susceptible mla6-m18982, the resistant bln1-m19089, and the susceptible double mutant (mla6+bln1)-m19028 (Chapman et al., 2021; Velásquez-Zapata et al., 2024).