CKX1 — Oryza sativa Indica Group

Summary

BGIOSGA007802 (CKX1) on chromosome 2 of Indica rice encodes a protein with cytokinin dehydrogenase activity (EC 1.5.99.12) that contains FAD-binding and cytokinin-binding domains. The gene is associated with cytokinin breakdown and metabolism, meristem and inflorescence development, and stomatal complex morphogenesis. It has been linked to grain yield, grain number, thousand grain weight, panicle and spikelet traits, plant height, leaf morphology, photosynthesis, and stress responses including salt and drought tolerance. Associations also include root system architecture, root development, adventitious root initiation, meristem size, leaf senescence, and abscisic acid responses. The protein is predicted to localise to plastids, chloroplast envelope, ER, vacuole, and nucleus. Studies of related genes in other species link the CKX family to root growth, flowering, salinity tolerance, disease resistance, and cytokinin level regulation.