《植物生理学报》 2016, 52(6): 868-876

杜梨质膜水孔蛋白基因PbPIP1的克隆与表达分析

冉昆^*, 孙晓莉^*, 张勇, 王宏伟, 魏树伟, 王少敏^**

山东省果树研究所, 山东泰安271000

通信作者：冉；E-mail: sdipwsm@163.com

摘　要：

采用RT-PCR和RACE技术从杜梨(Pyrus betulifolia)根系中克隆得到1个质膜内在蛋白(plasma membrane intrinsic proteins, PIPs)类的水孔蛋白基因全长cDNA序列, 命名为PbPIP1。该基因全长为1 297 bp, 包含1个870 bp的完整开放阅读框, 编码289个氨基酸。氨基酸序列分析表明, PbPIP1含有水孔蛋白家族高度保守的2个天冬酰胺-哺氨酸-丙氨酸基序(Asn-Pro-Ala, NPA)基序和6个跨膜区, 并具有高等植物特有的PIPs高度保守序列。聚类分析表明该基因编码蛋白属于PIP1亚家族。基因表达分析结果表明, PbPIP1在杜梨根、茎、叶中均有表达, 在根中表达量最高, 茎中最少。20% PEG处理时, 该基因在杜梨根系中的表达水平随胁迫时间的延长先上升后降低; 但在4°C低温、100 mmol•L^-1 NaCl处理时该基因的表达水平差异不明显。这说明PbPIP1可能主要在杜梨根系中发挥作用, 其表达丰度可能与杜梨的抗旱性密切相关。

关键词：杜梨; 水孔蛋白; 克隆; 表达分析

收稿：2015-12-04   修定：2016-04-06

资助：山东省自然科学基金(ZR2015YL075)、山东省农业科学院青年科研基金(2015YQN41)、山东省良种工程项目(梨优质矮化、多抗功能基因挖掘与种质创新利用 2014)、现代农业产业技术体系(CARS-29-31)和山东省果树研究所所长科研基金(2013KY03)。

Cloning and expression analysis of a plasma membrane aquaporion gene PbPIP1 in Pyrus betulifolia

RAN Kun^*, SUN Xiao-Li^*, ZHANG Yong, WANG Hong-Wei, WEI Shu-Wei, WANG Shao-Min^**

Shandong Institute of Pomology, Shandong, Taian 271000, China

Corresponding author: RAN Kun; E-mail: sdipwsm@163.com

Abstract:

A plasma membrane intrinsic proteins (PIPs) gene, designated PbPIP1, was cloned from the root of Pyrus betulifolia by RT-PCR and RACE methods. The full cDNA sequence of PbPIP1 was 1 297 bp, containing a complete open reading frame of 870 bp and encoding a putative protein with 289 amino acids. Bioinformatics analysis demonstrated that PbPIP1 exhibited two highly conserved NPA (Asn-Pro-Ala) motifs and a typical structure with six transmembrane domains, as well as the highly conserved sequence of higher plant specific PIPs. Phylogenetic analysis showed that PbPIP1 was belonged to PIP1 family. Gene expression analysis results showed that PbPIP1 was expressed in roots, stems and leaves, and the expression level was the highest in roots, and the lowest in stems. Under 20% PEG treatment for 72 hours, the expression level of PbPIP1 in the root of P. betulifolia was changed with time extension, which was firstly raised and then dropped. However, the expression level of PbPIP1 under 4°C temperature or 100 mmol•L^-1 NaCl treatment had no significant changes. These results indicated that PbPIP1 might play a role mainly in the root, and the expression abundance was closely related to drought resistance of P. betulifolia.

Key words: Pyrus betulifolia; aquaporin; clone; expression