Emergence of isochorismate-based salicylic acid biosynthesis within Brassicales.

ABSTRACT: Salicylic acid (SA) is a major defense phytohormone. In Arabidopsis thaliana, the isochorismate (IC) pathway is the primary route for pathogen-induced SA biosynthesis. First, the IC synthase (ICS) catalyzes the isomerization of chorismate to IC in chloroplasts. Second, the chloroplast-localized MATE transporter EDS5 appears to transport IC from chloroplasts to the cytosol. Cytosolic IC is then further converted to SA via the GH3 amino acid-conjugating enzyme PBS3. While this pathway is genetically well-characterized in A. thaliana, its evolutionary origin and conservation remain controversial. In this study, through comprehensive phylogenetic, structural, and functional analyses, we demonstrate that the IC pathway emerged within the Brassicales order in a time span between th

SUBMITTER: Hong K 

PROVIDER: S-EPMC12305054 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature