Abstract
NADH-GOGAT1 was mainly detected in the vascular bundles of developing organs suggesting an important role in reutilization of Gln, which is transported from source organs. In root, the NADH-GOGAT1 inducibly accumulated in two cell-layers of root surface by NH4+ supply, indicating a role in the primary assimilation of NH4+. In this work, a knock-out mutant by Tos17 insertion for OsNADH-GOGAT1 (nadh-gogat1) was isolated and characterized.
When seedlings of wild-type (WT) and nadh-gogat1 were hydroponically grown with 5 mM NH4+, root length of the nadh-gogat1 was reduced significantly. Although NH4+ uptake was identical, free ammonium ions highly accumulated in the nadh-gogat1 roots associated with the decrease in Glu, Asn and Asp. Since the phenotype appeared only in the roots at the seedling stage, hormonome analysis is currently investigated. In field condition, stem length, the number of panicle and dry weight of the mutant were decreased compared with WT.