Abstract
Rice plants have three homologous genes for cytosolic GS (GS1). In GS1 family, OsGS1;1 has the critical role for normal growth and grain filling in rice. However, in terms of regulatory relationships among nitrogen assimilation, growth, and changes of metabolic networks, the function of OsGS1;1 is not completely understood. To address this issue, metabolite and transcript profiling was conducted using OsGS1;1-knockout mutant. The metabolite profiles of the mutants showed the imbalance of sugars and amino acids in leaf blade, whereas those in roots displayed unique pattern. Metabolite-correlation analysis could capture the newly appeared metabolic networks in the mutant triggered from incomplete assimilation of ammonia. The integrated analysis using the results from metabolite correlations and microarrays can be revealed the distinct and important role of OsGS1;1 in both shoots and roots, in which it maintains the appropriate levels of metabolites for normal growth under continuous ammonium supply.
