Nitrate and ammonium are two major nitrogen (N) sources for higher plants, but they differ in utilization and signaling. MicroRNAs (miRNAs) play an essential role in N signal transduction; however, knowledge remains limited about the regulatory role of miRNAs responsive to different N sources, especially in crop plants. To get global overview on miRNAs involved in N response in rice, we performed high-throughput small RNA-sequencing under different nitrate and ammonium treatments. The results demonstrated that only 16 and 11 miRNAs were significantly induced by nitrate and ammonium under short-term treatment, respectively. However, 60 differentially expressed miRNAs were found between nitrate and ammonium under long-term cultivation. These results suggested that miRNA response greatly differentiates between nitrate and ammonium treatments. Furthermore, 44 miRNAs were found to be differentially expressed between high- and low-N conditions. Our study reveals comprehensive expression profiling of miRNAs responsive to different N sources and different N treatments, which advances our understanding on the regulation of different N signaling and homeostasis mediated by miRNAs.
Keywords: Ammonium; MicroRNA; Nitrate; Nitrogen; Rice.
Copyright © 2016 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.