Regulatory DNA elements in the primed systemic immunity of Arabidopsis thaliana
E. REIMER-MICHALSKI (1), S. Baum (1), A. Bolger (2), B. Usadel (2), V. Benes (3), U. Conrath (1) (1) Department of Plant Physiology, RWTH Aachen University, Germany; (2) Department of Botany and Molecular Genetics, RWTH Aachen University, Germany; (3) Genomics Core Facility, EMBO Laboratories, Germany

The plant immune system comprises various forms of inducible systemic immune responses. Systemic immunity develops after root colonization by beneficial microorganisms, chemical treatment, or upon foliar infection by microbes, which all can prime plants for a faster and/or stronger immune response for subsequent stress encounter. In Arabidopsis, defense priming is frequently associated with elevated levels of pattern-recognition receptors, accumulation of dormant signaling components, and alterations in chromatin state, especially histone modifications. The latter are known to loosen the interaction of nucleosomes, slack the ionic interaction of histone and DNA, and provide docking sites for regulatory proteins. This then results in the destabilization of chromatin structure, nucleosome extrusion, and promoter/gene loading with specific transcriptional regulators that prime the appropriate locus for enhanced transcription. Promoter/gene loading correlates with the formation of so-called ´open chromatin´. We developed the powerful formaldehyde-assisted isolation of regulatory elements (FAIRE) technique for leaves of Arabidopsis. We performed a FAIRE sequencing approach to provide a genome-wide map of open chromatin in the primed Arabidopsis defense response. This approach identified numerous known and unknown loci, as well as regulatory DNA elements, associated with the primed systemic immune response thus providing a platform for the understanding of systemic plant immunity.

Abstract Number: C15-3, P18-699
Session Type: Concurrent