Single-cell proteomic analysis of glucosinolate-rich S-cells in Arabidopsis thaliana

► We developed a method for plant single cell proteomic analysis. ► Glucosinolate-rich S-cells contain a distinctive set of enzymes and thus are metabolically active. ► S-cells contain enzymes from a methionine (precursor of glucosinolates) biosynthetic pathway. ► The majority of proteins found in S-cells are involved in membrane function and cellular organisation. ► Peptides belonging to myrosinases TGG1 and TGG2 were found in single S-cell samples.