P5CS — Oryza sativa Indica Group

Summary

BGIOSGA017932 (symbol P5CS, preferred name OiP5CS) on chromosome 5 of Indica rice encodes a bifunctional enzyme with glutamate 5-kinase and glutamylphosphate reductase activities (EC 2.7.2.11 and 1.2.1.41), conferring D1-pyrroline-5-carboxylate synthetase activity. The gene is associated with L-proline biosynthesis, the ascorbate-glutathione cycle, and responses to desiccation, oxidative stress, abscisic acid, and hyperosmotic salinity. It has been linked to salt and drought stress, ABA, and oxidative stress in rice. Associations also include grain yield, grain weight, amylose content, leaf chlorophyll content, photosynthetic rate, root length, and seed germination. The encoded protein localises to the cytoplasm, mitochondria, Golgi complex, and plasmodesmata. Studies of related genes in other species connect it to osmotic stress tolerance, root elongation under low water potential, and heat tolerance.