芹菜水孔蛋白基因AgPIP2;1的克隆及其对非生物胁迫的响应

为了研究芹菜质膜内在蛋白基因的序列特征及其在非生物胁迫条件下的表达特性,探讨其抗逆功能,以芹菜品种六合黄心芹为试验材料,通过RT-PCR技术克隆AgPIP2;1基因,通过生物信息学软件分析其核苷酸和氨基酸序列特征,并采用荧光定量PCR技术检测其在不同组织的表达及其对非生物胁迫的响应。结果表明,AgPIP2;1基因含有1个861 bp的开放阅读框,编码286个氨基酸,其编码的蛋白属于PIP2类蛋白。氨基酸序列分析显示,AgPIP2;1含有高度保守的NPA基序以及高等植物PIP蛋白的保守序列,与其他物种PIP2类蛋白具有较高的同源性,与胡萝卜DcPIP2;1的氨基酸序列同源性达到97.90%。在亲缘关系上与大豆GmPIP2;1、胡萝卜DcPIP2;1和绿豆VrPIP2;1较为接近。实时荧光定量PCR技术分析表明,AgPIP2;1基因在芹菜根、叶柄和叶片中均有表达,其中在叶片中的表达量最高,在根中的表达量最低,呈现比较明显的组织特异性。此外,AgPIP2;1基因受到高温、低温、干旱和盐等非生物胁迫的诱导,说明该基因可能参与芹菜抵御非生物胁迫的过程。本研究为进一步了解AgPIP2;1基因的功能及其在非生物胁迫中的作用奠定了基础。

Cloning of an Aquaporin Gene AgPIP2;1 From Celery and Its Response to Abiotic Stresses

To understand the sequence characteristics of the plasma membrane intrinsic protein (PIP) and its function in abiotic stress resistance, AgPIP2;1 gene was cloned from celery variety ‘Liuhe Huangxinqin’ by RT-PCR. The characteristics of the nucleotides and amino acids of the gene were analyzed by bioinformatics software, and its expression in different tissues and response to abiotic stress were detected by real-time quantitative PCR. The results showed that the gene contained an open reading frame of 861 bp, encoding 286 amino acids. The encoded protein belonged to PIP2 class. Amino acid sequence analysis showed that AgPIP2;1 had two highly conserved NPA motifs and conserved domains unique to PIP family in higher plants. AgPIP2;1 had high homology with PIP2 proteins from other species, and showed 97.90% homology with DcPIP2;1 in carrot. It is close to soybean GmPIP2;1, carrot DcPIP2;1, and Mung bean VrPIP2;1. Real-time quantitative PCR analysis showed that AgPIP2;1 gene was expressed in celery roots, petioles, and leaves, and exhibited the highest expression in the leaves and the lowest in the roots, showing obvious tissue specificity. In addition, the gene was induced by abiotic stresses such as high temperature, low temperature, drought, and salt, indicating that the gene may be involved in celery resistance against abiotic stresses. This study lay a foundation for further understand the function of AgPIP2;1 gene and its role in abiotic stress.