AAT — Beta vulgaris subsp. vulgaris

Summary

BvAAT (BVRB_5G126250) encodes a bifunctional aspartate aminotransferase and glutamate/aspartate-prephenate aminotransferase, belonging to the AspAT/PAT-like family with pyridoxal phosphate-dependent transaminase domains. The enzyme exhibits multiple aminotransferase activities, including LL-diaminopimelate, nicotianamine, and 1-aminocyclopropane-1-carboxylate synthase activity. In sugar beet, BvAAT is associated with amino acid metabolism, particularly L-phenylalanine anabolism, tyrosine breakdown, and ethylene anabolism. It is linked to systemic acquired resistance via salicylic acid-mediated signaling, embryo development ending in seed dormancy, and genetic transfer processes. The protein localizes to the amyloplast membrane and chloroplast stroma. BvAAT is associated with aromatic amino acid biosynthesis and parthenocarpic fruit development. Studies of related genes in other species link the family to nitrogen metabolism, protein stability, and traits including carotenoid and chlorophyll content, as well as root morphology.