Study : Salicylic acid inhibits transcriptional repression activities of its receptors to promote defense gene expression

Identification

Name

Salicylic acid inhibits transcriptional repression activities of its receptors to promote defense gene expression

Identifier

dXJuOkVWQS9zdHVkeS9QUkpOQTQzNDMxMw==

Source

Data link

Link to this study on EBI European Nucleotide Archive

Description

Salicylic acid (SA) is a plant defense hormone required for immunity. Arabidopsis NPR1 and NPR3/NPR4 were previously shown to bind SA and proposed as SA receptors. However, unlike NPR1, loss of NPR3/NPR4 does not block SA-induced defense gene expression. Here we report that NPR3/NPR4 function as transcriptional repressors and SA inhibits their activities to promote the expression of key immune regulators. npr4-4D, a newly identified gain-of-function allele that renders NPR4 unable to bind SA, constitutively represses SA-induced immune responses. In contrast, the equivalent mutation in NPR1 abolishes its function in promoting SA-induced defense gene expression. Further analysis revealed that npr4-4D and npr1-1 have additive effect on blocking SA-induced defense gene expression, suggesting that NPR4 and NPR1 function in parallel to regulate SA-induced immune responses. Our study reveals the molecular functions of SA receptors NPR3/NPR4 and uncovers a brand new mechanism of SA perception. Overall design: RNA-seq analysis of WT, npr1-1, npr4-4D, and npr1-1 npr4-4D arabidopsis seedlings untreated or treated with SA. 4 genotypes and 2 conditions, each with 2 biological replicates resulting in a total of 16 samples.

Data files

Genotype

Accession number	Name	Taxon