以扭果花旗杆(Dontostemon elegans Maxim.)为研究材料，克隆了前期转录组分析获得的盐胁迫下高表达的水通道蛋白(AQP)基因，命名为DePIP1;1，GenBank登录号OM864582。利用生物信息学方法分析该基因及蛋白序列，并进行表达模式分析；为进一步研究该基因抗逆分子调控机制，构建了过表达重组载体pCAMBIA1300-GFP∷DePIP1;1并遗传转化拟南芥〔Arabidopsis thaliana (Linn.) Heynh.〕，验证了转基因拟南芥的抗盐胁迫能力。结果表明：DePIP1;1基因cDNA全长864 bp，编码287个氨基酸；DePIP1;1蛋白的理论等电点为pI 9.14，相对分子质量为30 685.71，亲水性平均系数为0.384，无信号肽，定位于细胞膜，共有6个跨膜结构域，符合AQP家族典型结构特征。DePIP1;1蛋白的二级结构含49.48%无规卷曲、33.80% α螺旋和16.72%延伸链，三级结构预测结果显示该蛋白存在同型四聚体结构。系统进化树分析结果表明：DePIP1;1蛋白与盐芥〔Eutrema salsugineum (Pall.) Al-Shehbaz et Warwick〕和拟南芥PIP1;1蛋白的同源性较高。基因表达模式分析结果表明：DePIP1;1基因在花瓣、叶、雌雄蕊、茎和根中均有表达，其中，在茎中表达量最高，在根中表达量最低；在干旱（250 mmol·L^-1甘露醇）、盐（150 mmol·L^-1 NaCl）和冷（4 ℃）胁迫及10 μmol·L^-1脱落酸处理下，扭果花旗杆茎和叶中DePIP1;1基因表达上调明显，根中DePIP1;1基因仅对干旱和盐胁迫有轻微响应。在100和200 mmol·L^-1NaCl胁迫下，过表达DePIP1;1拟南芥株系的根长、侧根数、叶片数均高于野生型；在200 mmol·L^-1NaCl胁迫下，过表达DePIP1;1拟南芥株系的总叶绿素含量显著高于野生型；而过表达DePIP1;1拟南芥株系和野生型的相对含水量差异不明显。综上所述，DePIP1;1基因表达具有组织特异性，并受逆境和激素诱导；过表达DePIP1;1可提高拟南芥的抗盐性。

Taking Dontostemon elegans Maxim. as research material, an aquaporin (AQP) gene highly expressed under salt stress, which was previously identified in transcriptome analysis, was cloned and named as DePIP1;1, with the GenBank accession number of OM864582. The gene and protein sequences were analyzed by using bioinformatics methods, followed by expression pattern analysis; to further investigate the molecular regulatory mechanism of this gene in stress resistance, an overexpression recombinant vector pCAMBIA1300-GFP∷DePIP1;1 was constructed and genetically transformed into Arabidopsis thaliana (Linn.) Heynh., and the salt stress resistance ability in transgenic A. thaliana was verified. The results show that the full-length of cDNA of DePIP1;1 gene is 864 bp, encoding 287 amino acids; the theoretical isoelectric point of DePIP1;1 protein is pI 9.14, with a relative molecular mass of 30 685.71 and a hydrophilicity average coefficient of 0.384, without signal peptide, and it is localized on the plasma membrane and contains six transmembrane domains, conforming to typical structural characteristics of the AQP family. The secondary structure of DePIP1;1 protein consists of 49.48% random coils, 33.80% αhelixes, and 16.72% extended strands, and the tertiary structure prediction result shows that there is a homotetrameric structure in this protein. The phylogenetic tree analysis result indicates that DePIP1;1 protein shares relatively high homology with PIP1;1 proteins in Eutrema salsugineum (Pall.) Al-Shehbaz et Warwick and A. thaliana. The expression pattern analysis result reveals that DePIP1;1 is expressed in petals, leaves, stamens and pistils, stems, and roots, among which, the expression level is the highest in stems and the lowest in roots; under drought (250 mmol·L^-1 mannitol), salt (150 mmol·L^-1 NaCl), and cold (4 ℃) stresses as well as 10 μmol·L^-1 abscisic acid treatment, the expression of DePIP1;1 gene is evidently upregulated in stems and leaves of D. elegans, while DePIP1;1 gene in roots shows only slight responses to drought and salt stresses. Under 100 and 200 mmol·L^-1 NaCl stresses, DePIP1;1-overexpression A. thaliana lines exhibit greater root length, lateral root number, and leaf number than wild type; under 200 mmol·L^-1 NaCl stress, the total chlorophyll content in DePIP1;1-overexpression A. thaliana lines is significantly higher than that in wild type; while there is no obvious difference in relative water content between DePIP1;1-overexpression A. thaliana lines and wild type. In conclusion, the expression of DePIP1;1 gene  is tissue-specific, and is induced by adversity and hormones; overexpression of DePIP1;1 can enhance salt resistance of A. thaliana.