资源植物好好芭干旱应答基因PIP1功能及调控机理研究

Jojoba is a desert plant, a special industrial oil crop rising in the 1980s, having a very high economic value, very strong stress resistances,and it is an important genetic resources plant as well. My laboratory has been engaged in genetic research on Jojoba, particularly in recent years,succeeded in using Suppression Subtractive Hybridization to detect more than 300 ESTs of drought-induced express genes, and through network data analysis and RACE technology, a few coding sequences of genes were cloned, including the full length cDNA of ScPIP1 gene. PIP1 is an important gene involved in water metabolism and plant tolerances to abiostress, fortunately study of Jojoba PIP1(ScPIP1) has not yet been reported. This research forcus at studying the function of ScPIP1: the identfication of its subfamily by transformants analysis of mutant of Arabidopsis thaliana PIP1(AtPIP1),and evaluates its drought resistance via observation of phenotype variation, determination of physiological and biochemical changes, comparative analysis of ScPIP1 transgenic lines and wild type Arabidopsis thaliana. We are going to clarify the function and regulation mechanisms of ScPIP1 by analyzing its expression model on tissue specificity, subcellular localization and mRNA expression pattern of Jojoba both under normal and abiostress conditions, especially through cloning the promoter of ScPIP1 and the research on cis acting elements of it. Finally,we can evaluate truly the potential application and role of ScPIP1 in drought and salt tolerances.

好好芭是沙漠植物，是20世纪80年代崛起的特种工业油料作物，具有很高的经济价值，也具有很强的抗逆性，是重要遗传资源植物。本实验室多年来一直从事资源植物的遗传研究，特别近年来成功地利用消减杂交技术分离检测出300多个抗旱诱导表达基因的ESTs序列，通过网络数据分析和RACE技术克隆了一些基因的编码序列，包括PIP1基因cDNA全长。PIP1是重要的水分代谢基因，与植物抗逆性相关，但好好芭PIP1的研究尚未见报道。本研究旨在通过拟南芥突变体的ScPIP1转基因分析验证基因功能，利用PIP1转基因植物与野生型的表型和生理生化比对分析进行其抗旱功能的研究与评价；通过PIP1基因组织特异性表达分析和亚细胞定位，以及植物体PIP1 mRNA表达模式的分析；特别是通过ScPIP1的启动子克隆和顺式调控元件的研究；阐明ScPIP1基因功能与调控机制，对好好芭PIP1在植物抗旱、抗盐的作用作出评价。

好好芭是沙漠植物，有很强的抗逆性，特别是抗旱、耐高温性极强，是重要遗传资源植物，也是20世纪80年代崛起的特种油料作物，具有很高的经济价值。本项目采用RACE技术克隆了好好芭PIP1基因cDNA全长。PIP1是非常重要的一类水通道蛋白，资源植物好好芭PIP1的研究尚未见报道。对克隆到的基因编码产物进行氨基酸序列同源性分析，显示它与冰叶日中花的水通道蛋白有93%序列同源性。通过转基因拟南芥植株的抗旱性和抗盐性试验证明，过表达ScPIP1可提高拟南芥的抗旱性和抗盐性。我们发现ScPIP1对非生物胁迫的响应与减少膜损伤和增加脯氨酸的积累调节渗透性相关。同时发现拟南芥PIP1双突变体与野生型相比抗旱性和抗盐性都减弱。启动子特征分析证实，克隆出的PIP1启动子具有与干旱相关的MBS元件、响应茉莉酸甲酯相关的CGTCA-motif元件和TGACG-motif元件，及响应水杨酸相关的TCA-element元件、响应低温相关的LTR元件以及几个响应光诱导元件等。项目完成预期任务和目标，共发表学术论文12篇，申请发明专利4项，其中两项已获得授权。培养博士生4名，硕士生4名。