AO — Beta vulgaris subsp. vulgaris

Summary

BvAO (BVRB_6G135520) on sugar beet chromosome 6 encodes a copper-containing oxidase of the L-ascorbate oxidase family, with L-ascorbate oxidase activity, p-diphenol:oxygen oxidoreductase activity, copper binding and redox activity. The product is localised to the apoplast, plasmodesmata and extracellular space. In sugar beet, BvAO is associated with ascorbate catabolism, lignin breakdown, cell wall modification, flavonoid and ATP anabolism, lipid metabolism, and responses to hydrogen peroxide, salt, jasmonic acid, iron, virus and insects. It is linked to downregulation of antiviral response and upregulation of defense response to insect, as well as to respiration rate, salinity tolerance and iron transport. Studies of related genes in other species connect the family to traits including drought tolerance, chlorophyll content, quantum yield, shoot and root biomass, leaf area, flavonoid and sugar content, and spider mite resistance.