Research Advances in Elucidating the Function and Molecular Mechanism of the Nitrate Transporter 2 (NRT2) Proteins in Plants

doi:10.11983/CBB22134

Abstract

Abstract: Nitrogen, the essential macronutrient in plants, plays a critical role in regulating plant growth and development, especially for crops production. To gain high crop yield, a large amount N fertilizer is usually applied to the planting field. However, the excessive use of chemical fertilizers has aggravated the agricultural non-point source pollution (NSP). Increasing crop yield under reduced fertilizer consumption can be achieved by increasing nitrogen use efficiency (NUE), which is crucial for promoting sustainable agriculture and for achieving agriculture and food security. In response to nitrogen-deficiency condition under natural environments, high-affinity nitrate transporter 2 (NRT2) proteins have evolved in plants. Among them, NRT2.1 subfamily acts as the main component of nitrate uptake in roots under conditions of nitrate deficiency. Here we summarize the latest progresses of the function and molecular mechanism of the NRT2 proteins, particularly of the NRT2.1 subfamily in Arabidopsis and several important crops and discuss the future directions of NRT2 research. This review aims to provide an important basis for the subsequent exploration of the potential of NRT2 proteins in increasing crop yield and the underlying molecular mechanisms.

Key words: nitrogen, Nitrate Transporter 2, gene function, molecular mechanism

Huang Huimei, Gao Yongkang, Tai Yuying, Liu Chao, Qu Dejie, Tang Ruiheng, Wang Youning. Research Advances in Elucidating the Function and Molecular Mechanism of the Nitrate Transporter 2 (NRT2) Proteins in Plants[J]. Chinese Bulletin of Botany, 2023, 58(5): 783-798.

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URL: https://www.chinbullbotany.com/EN/10.11983/CBB22134

https://www.chinbullbotany.com/EN/Y2023/V58/I5/783

Figures/Tables 4

References 86

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基因名	位点	基因空间表达		低氮响应	功能	参考文献
基因名	位点	组织定位	亚细胞定位	低氮响应	功能	参考文献
拟南芥(Arabidopsis thaliana)
AtNRT2.1	AT1G08090	主根	细胞膜	诱导	介导高亲和硝酸盐吸收	Orsel et al., 2004; Little et al., 2005; Li et al., 2007
AtNRT2.2	AT1G08100	根	细胞膜	诱导	介导高亲和硝酸盐吸收	Orsel et al., 2004; Li et al., 2007
AtNRT2.3	AT5G60780	根	-	无	-	Okamoto et al., 2003
AtNRT2.4	AT5G60770	主根、侧根及茎的韧皮部	细胞膜	诱导	在极低浓度硝酸盐下介导NO₃^-吸收及转运	Kiba et al., 2012
AtNRT2.5	AT1G12940	主根和侧根的根毛区及韧皮部	细胞膜	抑制	氮饥饿下介导NO₃^-吸收及转运	Okamoto et al., 2003; Lezhneva et al., 2014
AtNRT2.6	AT3G45060	在所有组织中均表达, 在根和叶中高表达	细胞膜	无	响应病原菌侵染	Dechorgnat et al., 2012
AtNRT2.7	AT5G14570	种子	液泡膜	无	种子胚中的NO₃^-积累	Chopin et al., 2007
水稻(Oryza sativa)
OsNRT2.1	LOC_Os02g02190	主根和侧根	细胞膜	诱导	介导高亲和硝酸盐吸收	Feng et al., 2011; Naz et al., 2019
OsNRT2.2	LOC_Os02g02170	主根和侧根	细胞膜	诱导	介导高亲和硝酸盐吸收	Feng et al., 2011
OsNRT2.4	LOC_Os01g36720	侧根原基基部和茎	细胞膜	诱导	双亲和硝酸盐转运, 介导硝酸盐从源到库的再分配	Feng et al., 2011; Wei et al., 2018
OsNRT2.5/O-sNRT2.3a	LOC_Os01g50820	根部中柱木质部薄壁细胞	细胞膜	诱导	在极低浓度硝酸盐下介导NO₃^-从根部向地上部的长距离运输	Tang et al., 2012
OsNRT2.3b	LOC_Os01g50820	茎和叶的韧皮部, 在根中有微弱表达	细胞膜	无	介导NO₃^-转运, 感知韧皮部细胞的胞质pH值以平衡NO₃^?和NH₄⁺吸收	Feng et al., 2011; Ta- ng et al., 2012; Fan et al., 2016; Feng et al., 2017
玉米(Zea mays)
ZmNRT2.1	GRMZM2G010280_P01	根部皮层细胞	-	诱导	-	Trevisan et al., 2008
ZmNRT2.2	GRMZM2G010251_P01	皮层、中柱及侧根原基	-	诱导	-	Trevisan et al., 2008
ZmNRT2.3	GRMZM2G163866_P01	-	-	-	-	Plett et al., 2010
ZmNRT2.5	GRMZM2G455124_P01	在根、叶、穗轴、雄穗和苞叶中高表达	-	诱导	-	Fujita et al., 1995; Sabermanesh et al., 2017; Dechorgnat et al., 2019

基因名	位点	基因空间表达		低氮响应	功能	参考文献
基因名	位点	组织定位	亚细胞定位	低氮响应	功能	参考文献
拟南芥(Arabidopsis thaliana)
AtNRT2.1	AT1G08090	主根	细胞膜	诱导	介导高亲和硝酸盐吸收	Orsel et al., 2004; Little et al., 2005; Li et al., 2007
AtNRT2.2	AT1G08100	根	细胞膜	诱导	介导高亲和硝酸盐吸收	Orsel et al., 2004; Li et al., 2007
AtNRT2.3	AT5G60780	根	-	无	-	Okamoto et al., 2003
AtNRT2.4	AT5G60770	主根、侧根及茎的韧皮部	细胞膜	诱导	在极低浓度硝酸盐下介导NO₃^-吸收及转运	Kiba et al., 2012
AtNRT2.5	AT1G12940	主根和侧根的根毛区及韧皮部	细胞膜	抑制	氮饥饿下介导NO₃^-吸收及转运	Okamoto et al., 2003; Lezhneva et al., 2014
AtNRT2.6	AT3G45060	在所有组织中均表达, 在根和叶中高表达	细胞膜	无	响应病原菌侵染	Dechorgnat et al., 2012
AtNRT2.7	AT5G14570	种子	液泡膜	无	种子胚中的NO₃^-积累	Chopin et al., 2007
水稻(Oryza sativa)
OsNRT2.1	LOC_Os02g02190	主根和侧根	细胞膜	诱导	介导高亲和硝酸盐吸收	Feng et al., 2011; Naz et al., 2019
OsNRT2.2	LOC_Os02g02170	主根和侧根	细胞膜	诱导	介导高亲和硝酸盐吸收	Feng et al., 2011
OsNRT2.4	LOC_Os01g36720	侧根原基基部和茎	细胞膜	诱导	双亲和硝酸盐转运, 介导硝酸盐从源到库的再分配	Feng et al., 2011; Wei et al., 2018
OsNRT2.5/O-sNRT2.3a	LOC_Os01g50820	根部中柱木质部薄壁细胞	细胞膜	诱导	在极低浓度硝酸盐下介导NO₃^-从根部向地上部的长距离运输	Tang et al., 2012
OsNRT2.3b	LOC_Os01g50820	茎和叶的韧皮部, 在根中有微弱表达	细胞膜	无	介导NO₃^-转运, 感知韧皮部细胞的胞质pH值以平衡NO₃^?和NH₄⁺吸收	Feng et al., 2011; Ta- ng et al., 2012; Fan et al., 2016; Feng et al., 2017
玉米(Zea mays)
ZmNRT2.1	GRMZM2G010280_P01	根部皮层细胞	-	诱导	-	Trevisan et al., 2008
ZmNRT2.2	GRMZM2G010251_P01	皮层、中柱及侧根原基	-	诱导	-	Trevisan et al., 2008
ZmNRT2.3	GRMZM2G163866_P01	-	-	-	-	Plett et al., 2010
ZmNRT2.5	GRMZM2G455124_P01	在根、叶、穗轴、雄穗和苞叶中高表达	-	诱导	-	Fujita et al., 1995; Sabermanesh et al., 2017; Dechorgnat et al., 2019

转录因子	转录因子蛋白家族	靶基因(NRT)	结合元件/位点	参考文献
初级硝酸盐信号途径
NLP6	RWP-RK	NRT1.1/NPF6.3和NRT2.1	NRE	Konishi and Yanagisawa, 2013
NLP7	RWP-RK	NRT1.1/NPF6.3、NRT2.1和NRT2.2	NRE	Yu et al., 2016
LjNLP1	RWP-RK	LjNRT2.1	NRE	Marchive et al., 2013
NIGT1	NIGT	NRT2.1	GAATC	Maeda et al., 2018
TGA1/TGA4	bZIP	NRT2.1和NRT2.2	TGACG	Alvarez et al., 2014
LBD37/38/39	ASL/LBD	NRT2.1和NRT2.2	GCGGCG	Rubin et al., 2009
系统性硝酸盐信号通路
TCP20	TCP	NRT1.1/NPF6.3和NRT2.1	GCCCR	Guan et al., 2014
HY5	bZIP	NRT2.1	C/G box	Chen et al., 2016b

转录因子	转录因子蛋白家族	靶基因(NRT)	结合元件/位点	参考文献
初级硝酸盐信号途径
NLP6	RWP-RK	NRT1.1/NPF6.3和NRT2.1	NRE	Konishi and Yanagisawa, 2013
NLP7	RWP-RK	NRT1.1/NPF6.3、NRT2.1和NRT2.2	NRE	Yu et al., 2016
LjNLP1	RWP-RK	LjNRT2.1	NRE	Marchive et al., 2013
NIGT1	NIGT	NRT2.1	GAATC	Maeda et al., 2018
TGA1/TGA4	bZIP	NRT2.1和NRT2.2	TGACG	Alvarez et al., 2014
LBD37/38/39	ASL/LBD	NRT2.1和NRT2.2	GCGGCG	Rubin et al., 2009
系统性硝酸盐信号通路
TCP20	TCP	NRT1.1/NPF6.3和NRT2.1	GCCCR	Guan et al., 2014
HY5	bZIP	NRT2.1	C/G box	Chen et al., 2016b