Affects Nitrogen Metabolism by Sucrose Transport Signaling in Rice ( L.).

Carbon and nitrogen antagonistically regulate multiple developmental processes. However, the molecular mechanism affecting nitrogen metabolism by sucrose transport remains poorly defined. Previously, we noted that () mediated sucrose transport by binding to the promoter regions of (), , and . Here, we note that promotes nitrogen uptake and then maintains the ratio of fresh weight to dry weight in seedling plants and the effective leaf blade at flowering stages. Mutants of the sucrose transporter gene displayed a phenotype similar to that of . By microarray analysis and qRT-PCR in mutant plants, affected the transcription level of amino acid metabolism-related genes. We further found that mainly amino acid contents were reduced in flag leaves but increased in seeds. Both sugar and organic nitrogen changes caused the ratio of fresh weight to dry weight to decrease in mutant seedling plants and mature leaves, which might result in vigorous reduced metabolic activity and become less susceptible to stress. These results demonstrated that affected nitrogen metabolism by sugar distribution in rice, which provided new insight that coordinated with C and N balance to maintain plant growth activity.