College of Agronomy and Biotechnology, Southwest University, Chongqing 400716, China.
Academy of Agricultural Sciences, Southwest University, Chongqing 400716, China.
Int J Mol Sci. 2022 Apr 29;23(9):4965. doi: 10.3390/ijms23094965.
Nitrate transporter 2 (NRT2) plays an essential role in Nitrogen (N) uptake, transport, utilization, and stress resistance. In this study, the NRT2 gene family in two sequenced ecotypes were identified, including 31 genes in 'Zhongshuang11' () and 19 in 'Darmor-' (). The candidate genes were divided into three groups (Group I-III) based on phylogenetic analyses, supported by a conserved intron-exon structure in each group. Collinearity analysis revealed that the large expansion of attributed to allopolyploidization of ancestors and , and small-scale duplication events in . Transcription factor (TF) binding site prediction, -element analysis, and microRNA prediction suggested that the expressions of are regulated by multiple factors, and the regulatory pattern is relatively conserved in each group and is tightly connected between groups. Expression assay showed the diverse and differentiated spatial-temporal expression profiles of in Group I, but conserved patterns were observed in Group II/III; and the low nitrogen (LN) stress up-regulated expression profiles were presented in Group I-III, based on RNA-seq data. RT-qPCR analyses confirmed that and in Group II were highly up-regulated under LN stress in roots. Our results offer valid information and candidates for further functional studies.
硝酸盐转运蛋白 2 (NRT2) 在氮 (N) 的吸收、转运、利用和抗逆性方面发挥着重要作用。在这项研究中，从两个已测序的生态型中鉴定出了 NRT2 基因家族，包括'中双 11'()中的 31 个基因和'Darmor-'()中的 19 个基因。候选基因根据系统发育分析分为三组（I-III 组），每组都有保守的内含子-外显子结构支持。共线性分析表明，'的大量扩张归因于祖先和的异源多倍化，而在中发生了小规模的重复事件。转录因子（TF）结合位点预测、顺式作用元件分析和 microRNA 预测表明，的表达受到多种因素的调控，并且在每组内的调控模式相对保守，在组间紧密相连。表达分析表明，I 组中的表现出多样且分化的时空表达模式，但在 II/III 组中观察到保守模式；根据 RNA-seq 数据，I-III 组在低氮 (LN) 胁迫下呈现上调表达模式。RT-qPCR 分析证实，II 组中的和在 LN 胁迫下在根中高度上调。我们的结果为进一步的功能研究提供了有效的信息和候选基因。
