Sensing and Uptake of Nitrogen in Rice Plant: A Molecular View

doi:10.1016/j.rsci.2018.12.007

Abstract

Abstract:

As a main feature of plant autotrophy, assimilation of inorganic nitrogen (N) is not only of fundamental interest to the crop, but also a crucial factor in crop productivity. N is the main plant mineral nutrient needed for chlorophyll production and other plant cell components (proteins, nucleic acids and amino acids). I highlighted the novel aspects of N responsive sensors, transporters and signaling molecules recently identified in the monocot rice plant, and discussed their potential roles in N sensing and transporting. Furthermore, over the last couple of years, N sensing has been shown to be affected by different external factors, which act as local signals to trigger systemic signaling coordinated by long-distance transport or mobile signals in plant body. Understanding of this complex regulatory network provides a foundation mechanism for the development of novel strategies to increase the acquisition and transportation efficiency of nitrogen under varying N conditions for rice production.

Key words: rice, nitrate signaling, gene function

Saiful Islam Md. Sensing and Uptake of Nitrogen in Rice Plant: A Molecular View[J]. Rice Science, 2019, 26(6): 343-355.

Figures/Tables 4

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Gene	Gene locus	Function	Spatial expression	Transcriptional regulation by N	Effect on plant development	Reference
OsAMT1.1	LOC_Os04g43070	Dual-affinity NH₄⁺ transporter, root-to-shoot transporter	Root epidermis and vascular tissues, root-shoot junction, vascular bundle, and leaf mesophyll cells	Induced by NH₄⁺ and repressed by N starvation	Promote root growth and grain yield	Ranathunge et al, 2014; Li et al, 2016; Sonoda et al, 2003b
OsAMT1.2	LOC_Os02g40710	NH₄⁺ transporter	Vascular tissues, endodermis and pericycle in primary root tip	Induced by NH₄⁺ and repressed by N starvation	Unknown	Sonoda et al, 2003a, b
OsAMT1.3	LOC_Os02g40730	NH₄⁺ transporter	Root vascular tissue and lateral root primordia	Repressed by NH₄⁺ and induced by N starvation	Promote root elongation	Sonoda et al, 2003a, b; Ferreira et al, 2015
OsAMT2.1	LOC_Os05g39240	Low-affinity NH₄⁺ transporter	Root, shoot, leaf blade and sheath	Irresponsive to N supply	Unknown	Suenaga et al, 2003
OsAMT2.2	LOC_Os01g61510	NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsAMT2.3	LOC_Os01g61550	NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsAMT3.1	LOC_Os01g65000	Putative NH₄⁺ transporter	Unknown	Induced by N starvation	Unknown	Suenaga et al, 2003
OsAMT3.2	LOC_Os03g62200	Putative NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsAMT3.3	LOC_Os02g34580	Putative NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsAMT4	LOC_Os03g53780	Putative NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsNRT1.1b	LOC_Os10g40600	Dual-affinity NO₃^- transporter	Root epidermis, hairs and vascular tissues, and leaf sheath, leaf blade and culm	Induced by NO₃^-	Grain yield increase	Hu et al, 2015
OsNPF2.4	LOC_Os03g48180	Low-affinity NO₃^- transporter, root-to-shoot transporter	Root epidermis, xylem parenchyma, and phloem companion cells and leaf phloem	Induced by high NO₃^- supply	Promote root growth and biomass, and grain yield	Xia et al, 2015
OsNRT2.1	LOC_Os02g02170	High-affinity NO₃^- transporter	Abundantly expressed in most cell types in root, but weakly expressed in shoot	Induced by NO₃^-and repressed by NH₄⁺	Unknown	Feng et al, 2011
OsNRT2.2	LOC_Os02g02190	High-affinity NO₃ transporter	Abundantly expressed in most cell types in roots, but weakly expressed in shoot	Induced by NO₃^- and repressed by NH₄⁺	Unknown	Feng et al, 2011
OsNRT2.3a	LOC_Os01g50820	High-affinity NO₃^-transporter, transport nitrate from root to shoot, not root nitrate uptake	Vascular tissues at root and root-shoot junction	Induced by NO₃^- and repressed by NH₄⁺	Promote root growth and biomass	Feng et al, 2011; Tang et al, 2012
OsNRT2.3b	LOC_Os01g50820	High-affinity NO₃^- transporter, sensing cytosolic pH changes	Vascular tissue, mainly in phloem in both root and shoot	Irresponsive to N supply	Improved grain yield and nitrogen use efficiency	Feng et al, 2011
OsNRT2.4	LOC_Os01g36720	Putative high-affinity NO₃^-transporter	Lateral root primordia and shoot vascular tissues	Induced by NO₃^-and repressed by NH₄⁺	Unknown	Feng et al, 2011
OsNAR2.1	LOC_Os02g38230	Partner proteins of OsNRT2.1, OsNRT2.2 and OsNRT2.3a	Epidermis and vascular tissue in root and shoot	Induced by NO₃^- and repressed by NH₄⁺	Promote root and shoot growth	Feng et al, 2011; Yan et al, 2011
OsNAR2.2	LOC_Os04g40410	Putative partner protein of OsNRT2s	Unknown	Induced by high NO₃^- and NH₄⁺	Unknown	Yan et al, 2011

Gene	Gene locus	Function	Spatial expression	Transcriptional regulation by N	Effect on plant development	Reference
OsAMT1.1	LOC_Os04g43070	Dual-affinity NH₄⁺ transporter, root-to-shoot transporter	Root epidermis and vascular tissues, root-shoot junction, vascular bundle, and leaf mesophyll cells	Induced by NH₄⁺ and repressed by N starvation	Promote root growth and grain yield	Ranathunge et al, 2014; Li et al, 2016; Sonoda et al, 2003b
OsAMT1.2	LOC_Os02g40710	NH₄⁺ transporter	Vascular tissues, endodermis and pericycle in primary root tip	Induced by NH₄⁺ and repressed by N starvation	Unknown	Sonoda et al, 2003a, b
OsAMT1.3	LOC_Os02g40730	NH₄⁺ transporter	Root vascular tissue and lateral root primordia	Repressed by NH₄⁺ and induced by N starvation	Promote root elongation	Sonoda et al, 2003a, b; Ferreira et al, 2015
OsAMT2.1	LOC_Os05g39240	Low-affinity NH₄⁺ transporter	Root, shoot, leaf blade and sheath	Irresponsive to N supply	Unknown	Suenaga et al, 2003
OsAMT2.2	LOC_Os01g61510	NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsAMT2.3	LOC_Os01g61550	NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsAMT3.1	LOC_Os01g65000	Putative NH₄⁺ transporter	Unknown	Induced by N starvation	Unknown	Suenaga et al, 2003
OsAMT3.2	LOC_Os03g62200	Putative NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsAMT3.3	LOC_Os02g34580	Putative NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsAMT4	LOC_Os03g53780	Putative NH₄⁺ transporter	Unknown	Unknown	Unknown	Suenaga et al, 2003
OsNRT1.1b	LOC_Os10g40600	Dual-affinity NO₃^- transporter	Root epidermis, hairs and vascular tissues, and leaf sheath, leaf blade and culm	Induced by NO₃^-	Grain yield increase	Hu et al, 2015
OsNPF2.4	LOC_Os03g48180	Low-affinity NO₃^- transporter, root-to-shoot transporter	Root epidermis, xylem parenchyma, and phloem companion cells and leaf phloem	Induced by high NO₃^- supply	Promote root growth and biomass, and grain yield	Xia et al, 2015
OsNRT2.1	LOC_Os02g02170	High-affinity NO₃^- transporter	Abundantly expressed in most cell types in root, but weakly expressed in shoot	Induced by NO₃^-and repressed by NH₄⁺	Unknown	Feng et al, 2011
OsNRT2.2	LOC_Os02g02190	High-affinity NO₃ transporter	Abundantly expressed in most cell types in roots, but weakly expressed in shoot	Induced by NO₃^- and repressed by NH₄⁺	Unknown	Feng et al, 2011
OsNRT2.3a	LOC_Os01g50820	High-affinity NO₃^-transporter, transport nitrate from root to shoot, not root nitrate uptake	Vascular tissues at root and root-shoot junction	Induced by NO₃^- and repressed by NH₄⁺	Promote root growth and biomass	Feng et al, 2011; Tang et al, 2012
OsNRT2.3b	LOC_Os01g50820	High-affinity NO₃^- transporter, sensing cytosolic pH changes	Vascular tissue, mainly in phloem in both root and shoot	Irresponsive to N supply	Improved grain yield and nitrogen use efficiency	Feng et al, 2011
OsNRT2.4	LOC_Os01g36720	Putative high-affinity NO₃^-transporter	Lateral root primordia and shoot vascular tissues	Induced by NO₃^-and repressed by NH₄⁺	Unknown	Feng et al, 2011
OsNAR2.1	LOC_Os02g38230	Partner proteins of OsNRT2.1, OsNRT2.2 and OsNRT2.3a	Epidermis and vascular tissue in root and shoot	Induced by NO₃^- and repressed by NH₄⁺	Promote root and shoot growth	Feng et al, 2011; Yan et al, 2011
OsNAR2.2	LOC_Os04g40410	Putative partner protein of OsNRT2s	Unknown	Induced by high NO₃^- and NH₄⁺	Unknown	Yan et al, 2011