Does chromatin remodeling mark systemic acquired resistance?
The recognition of plant pathogens activates local defense responses and triggers a long-lasting systemic acquired resistance (SAR) response. Activation of SAR requires the hormone salicylic acid (SA), which induces SA-responsive gene expression. Recent data link changes in gene expression to chromatin remodeling, such as histone modifications and histone replacement. Here, we propose a model in which recruitment of chromatin-modifying complexes to SA-responsive loci controls their basal and SA-induced expression. Basal repression of these loci requires the post-translational modifier SUMO (SMALL UBIQUITIN-LIKE MODIFIER). This is of particular relevance because SUMO conjugation has been shown to control the activity, assembly and disassembly of chromatin-modifying complexes to transcription complexes. Chromatin remodeling could be instrumental for priming of SA-responsive loci to enable their enhanced reactivation upon subsequent pathogen attack.
van den Burg
Harrold A
HA
Laboratory of Phytopathology, Wageningen University, Binnenhaven 5, 6709 PD Wageningen, The Netherlands.
Takken
Frank L W
FL
D042002:Chromatin Assembly and Disassembly / Q000235:genetics / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000502:physiology; D007113:Immunity, Innate / Q000502:physiology*; D020156:Salicylic Acid / Q000494:pharmacology
D020156:Salicylic Acid