中文摘要：

以拟南芥（Arabidopsis thaliana）和莱茵衣藻（Chlamydomonas reinhardttii）高亲和性硝酸根转运蛋白（NRT2s）为对照,对毛果杨（Populus trichocarpa）NRT2s家族成员进行序列比对、系统发育分析、基因结构分析、理化性质预测、疏水性与跨膜区预测、结构域检测等生物信息学分析。结果表明：毛果杨基因组包含6个NRT2s家族成员并可分为3个亚家族。其中PtNRT2.1、PtNRT2.2和PtNRT2.3属于亚家族I;PtNRT2.4和PtNRT2.5属于亚家族II;PtNRT2.6属于亚家族III。亚家族I保守程度最高,亚家族II和III可能由亚家族I进化而来。所有的NRT2s都具有高度相似的结构域、功能区和基因结构,在不同物种中的进化较为保守。不同的NRT2s成员定位于不同的亚细胞结构中,其具体功能可能存在差异,并共同参与调控杨树的硝态氮平衡。

英文摘要：

Based on gene sequences of putative high affinity nitrate transporters （NRT2s） in Populus tricho- carpa, gene structures, physicochemical parameters, hydrophobicity, subcellular localization, transmern- brahe regions and conserved domains were predicted with bioin{ormatics methods using NRT2s in Arabi- dopsis thaliana （AtNRT2s） and Chlamydornonas reinhardttii （CreNRT2s） as comparison. In P. tricho- carpa there were 6 NRT2s family members named as PtNRT2. 1, PtNRT2.2, PtNRT2. S, PtNRT2.4, PtNRT2.5 and PtNRT2.6, which could be divided into 3 subfamilies according to their highly conserved sequences and functional domains. PtNRT2.1, PtNRT2.2, and PtNRT2.3 could be in subfamily Ⅰ, while PtNRT2.4, PtNRT2.5 in subfamily Ⅱ and PtNRT2.6 in subfamily Ⅲ. Although PtNRT2s had similar a- mino acid sequences, they showed variations in subcellular localization. These data indicated that PtNRT2s probably play different roles in nitrate balance in P. trichocarpa.