龙眼水通道蛋白基因(DLPIP1)的克隆与表达分析

应用蛋白质组学研究低温胁迫下龙眼叶片蛋白质组变化时,发现PIP1蛋白在龙眼低温胁迫中上调表达。应用RACE技术克隆龙眼水通道蛋白基因全长cDNA,命名为DLPIP1,基因登陆号为JN572691,长度为1 132 bp,包括1个900 bp的开放阅读框,编码299个氨基酸序列,同源性分析表明,DLPIP1在21个不同植物中的一致性为90%~93%。应用生物信息学软件对DLPIP1氨基酸序列分析表明,含有7个跨膜区,有2个NPA单元,其氨基酸残基与MIP家族蛋白保守区序列完全一致。氨基酸序列比对发现,该序列与其他物种PIP质膜水通道蛋白氨基酸序列有很高的同源性。利用实时荧光定量技术对DLPIP1在低温胁迫下不同组织表达谱分析表明,DLPIP1在龙眼根、茎、叶中都有表达,在根中的表达量最高,其次是茎和叶。DLPIP1在低温胁迫时,随着低温胁迫时间的延长而发生变化。这说明DLPIP1蛋白在龙眼低温逆境过程中起作用。

Cloning and expression of longan aquaporin(DLPIP1)gene

The protein expressions under low temperature stress were studied using proteomics method.The results showed that the expression of DLPIP1 protein was up-regulated.The full length of DLPIP1 cDNA obtained by RT-PCR was 1 132 bp with a 900 bp open read frame which encoded a putative DLPIP1 protein with 299 amino acids.Comparison of the amino acid sequence homology among DLPIP1 proteins from 21 different species indicated that DLPIP1 protein had a range of 90% to 93% identity with homologues of other plants.Bioinformatics analysis demonstrated that DLPIP1 exhibited a typical structure with seven membrane-spanning domains and an internal symmetry showing two highly conserved NPA motifs and possessing the MIP family signal consensus sequence.The DLPIP1 amino acids showed high identity with the PIP plasmalemma subfamily of other 21 plant species by homology comparison analysis.Quantitative real-time PCR results showed that the DLPIP1 expressed in root,stem and leaf,while the amount of expressions were different in different organs.The mRNA of DLPIP1 was the most abundant in root,the least in leaf and stem.Furthermore,the mRNA of DLPIP1 changed with time extension under low temperature stress.These results suggested that DLPIP1 might be involved in function of chilling stress.