Repeated rearrangement of the GSL‐AOP locus contributed to spatio‐temporal variation in defense chemistry in Arabidopsis

Abstract

Plants coordinate metabolic and developmental processes with the help of genetically variable, interconnected regulatory networks. The GSL-AOP locus in Arabidopsis thaliana encodes enzymes involved in the biosynthesis of glucosinolate defense compounds and has been attributed regulatory functions e.g. in flowering time control. To correlate genetic and phenotypic variation linked to GSL-AOP, we conducted a phylogenetic analysis across 1135 accessions and found that the available short-read sequencing data does not fully resolve the structural diversity in the locus. We analyzed a selection of 74 accessions for glucosinolate profiles and flowering time under different conditions and acquired long-read sequence information for glucosinolate and flowering time loci. Especially in the Caucasus region, structural variation in GSL-AOP was associated with conditional, tissue-specific glucosinolate profiles. Variation in FLC among the Caucasian accessions correlated with variation in the flowering time response to vernalization, suggesting that local adaptation has shaped defense and development in an orchestrated manner.