IC4R018-RNA-Seq-2015-25447912

Project Title

• RNA-Seq analysis of differentially expressed genes in rice under varied nitrogen supplies

The Background of This Project

• Ammonium (NH4 +) and nitrate (NO3 −) are the two main forms of inorganic nitrogen (N) available for plant growth (Chen et al., 1998). In general, ammonium is the preferred nitrogen source for many plant species over nitrate because of its lower energy demand for metabolism.It's reported that ammonium ion is not only the primary nitrogen nutrient for rice growth and development in paddies of tropical Asia(Yu, 1985) but also the chief limiting factor for rice production.
• The Oryza sativa ammonium transporter,OsAMT1;1, more constitutive expression in shoots and roots, was a prominent member of the OsAMT1 gene family that involved in NH4 + transport in rice plants (Sonoda et al., 2003a). Meanwhile, NH4 + uptake had been reported to be subjected to negative feedback, supposedly from nitrogen metabolites (Lee and Rudge, 1986; Morgan and Jackson,1988; Sonoda et al., 2003b); the early intermediates of nitrogen metabolism such as glutamine might control the expression of ammonium transporter genes in rice and serve as indicators of both the environmental and the cytosolic nitrogen status in rice.
• With the rapid development of bioengineering and molecular biological technologies, transgenic approaches have broadly been applied to enhance nitrogen uptake and assimilation in rice by the overexpression of novel transgenes. Gene expression, the NH4 + permeability as well as the uptake rate in overexpressed OsAMT1;1 lines were much higher than wild type (WT), meanwhile, higher NH4 + contents also promoted higher expression levels of genes in the nitrogen assimilation pathway, resulting in greater nitrogen assimilates, chlorophyll, starch, sugars, and grain yield in transgenic lines than in the WT under both suboptimal and optimal nitrogen conditions, these results implicated that OsAMT1;1 had the potential to improve nitrogen use efficiency and grain yield in rice (Ranathunge et al., 2014).
• Following the discovery of the major role of the enzyme couple glutamine synthetase (GS) and glutamate synthase (GOGAT) in ammonium assimilation in higher plants (Good et al., 2004; Miflin and Lea, 1976),several laboratories had focused on understanding the mechanisms controlling the regulation of this pathway in plants including rice (Cai et al.,2009; Harrison et al., 2000; Kusano et al., 2011).

Labs working on this Project

• State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
• University of Chinese Academy of Sciences, Beijing 100049, China
• Institute of Horticulture, Jiangsu Academy of Agricultural Sciences, Nanjing 210008, China

Corresponding Author

• Shun-ying Yang: yhsu@issas.ac.cn