Abstract

Plants have evolved efficient defence systems against pathogens that often rely on specific transcriptional responses. Priming is part of the defence syndrome, by establishing a hypersensitive state of defence genes such as after a first encounter with a pathogen. Because activation of defence responses has a fitness cost, priming must be tightly controlled to prevent spurious activation of defence. However, mechanisms that repress defence gene priming are poorly understood. Here, we show that the histone chaperone CAF-1 is required to establish a repressed chromatin state at defence genes. Absence of CAF-1 results in spurious activation of a salicylic acid-dependent pathogen defence response in plants grown under non-sterile conditions. Chromatin at defence response genes in CAF-1 mutants under non-inductive (sterile) conditions is marked by low nucleosome occupancy and high H3K4me3 at transcription start sites, resembling chromatin in primed wild-type plants. We conclude that CAF-1-mediated chromatin assembly prevents the establishment of a primed state that may under standard non-sterile growth conditions result in spurious activation of SA-dependent defence responses and consequential reduction of plant vigour.

Published in

Nature Plants
2015, Volume: 1, number: 9, article number: 15127
Publisher: NATURE PUBLISHING GROUP

SLU Authors

• Mozgova, Iva

  • Department of Plant Biology, Swedish University of Agricultural Sciences
    

• Liu, Qinsong

  • Department of Plant Biology, Swedish University of Agricultural Sciences
    

• Hofius, Daniel

  • Department of Plant Biology, Swedish University of Agricultural Sciences
    

• Hennig, Lars

  • Department of Plant Biology, Swedish University of Agricultural Sciences
    

Associated SLU-program

SLU Plant Protection Network


UKÄ Subject classification

Plant Biotechnology
Developmental Biology


Publication identifier

DOI: https://doi.org/10.1038/NPLANTS.2015.127

Permanent link to this page (URI)

https://res.slu.se/id/publ/72371