AO — Capsicum annuum

Summary

T459_30356 (AO, CaASO, CaAO, CaMCO1) on pepper chromosome 12 encodes a copper-containing L-ascorbate oxidase, a member of the multicopper oxidase family with cupredoxin domains, and exhibits L-ascorbate oxidase and p-diphenol:oxygen oxidoreductase activities. The gene is associated with ascorbate catabolism, lignin breakdown, carotenoid and phenylpropanoid anabolism, sucrose metabolism, fruit development and ripening, and responses to hydrogen peroxide, stress, virus, jasmonic acid, and iron. It is linked to downregulation of antiviral responses and upregulation of defense responses to insects, as well as ABA signaling and homeostasis. The product localizes to the apoplast, plasmodesma, and extracellular space. Associations include respiration rate, ascorbic acid content and biosynthesis, and iron transport. Studies of related genes in other species link the family to traits including drought tolerance, chlorophyll content, oxidative stress response, and spider mite susceptibility.