GAD — Sorghum bicolor

Summary

SORBI_3007G152800, designated SbGAD1 on sorghum chromosome 7, encodes a glutamate decarboxylase (EC 4.1.1.15) that also exhibits sphinganine-1-phosphate aldolase activity, binds pyridoxal phosphate and calmodulin, and belongs to the pyridoxal-phosphate-dependent decarboxylase family. The gene is associated with glutamate and sphingolipid breakdown, glutamate and carboxylic acid metabolism, and GABA formation, and its product localises to the cytosol, endoplasmic reticulum and ER membrane. SbGAD1 has been linked to grain filling period, photosynthetic rate, grain yield and drought tolerance. Studies of the rice relative OsGAD1 connect the family to root, seed and shoot phenotypes, and broader sequence-similarity evidence links the family to traits including grain length, germination rate, cold tolerance, salinity tolerance, submergence response, and nitrate uptake.