Chromatin assembly factor CAF-1 represses priming of plant defence response genes.
Nat Plants
; 1: 15127, 2015 Sep 01.
Article
em En
| MEDLINE
| ID: mdl-27250680
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.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Nat Plants
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Suécia