猕猴桃POD基因的克隆和表达分析

Cloning and Expression Analysis of POD Genes in Kiwifruit

摘要:

为了解猕猴桃POD基因的表达调控功能，采用RT-PCR技术从‘米良1号’猕猴桃（Actinidia deliciosa ‘Miliang-1’）克隆了2个POD家族成员基因（AdPOD27和AdPOD64）。结果表明，AdPOD27和AdPOD64开放阅读框分别为984和957 bp，预测分别编码327和318个氨基酸，GenBank登录号分别为MF774100和MF774101。AdPOD27和AdPOD64为亲水性碱性蛋白，属于植物亚铁红素依赖Ⅲ型POD超家族成员，含有信号肽、跨膜螺旋结构和磷酸化位点，亚细胞定位预测分别定位于线粒体和细胞外。qRT-PCR结果表明，AdPOD27在脱落酸（ABA）和4℃处理时表达量急剧上升，而AdPOD64只在ABA处理时表达量显著提高。此外，AdPOD27表达量与POD活性、AdPOD64表达量均存在显著相关性。因此，AdPOD27和AdPOD64可能在猕猴桃果实软化、低温响应和ABA诱导等过程中发挥重要的调控功能。

Abstract:

To understand the regulation function of peroxidase genes in kiwifruit, two members of POD gene family (AdPOD27 and AdPOD64) were cloned from Actinidia deliciosa ‘Miliang-1’ by using reverse transcription PCR, the bioinformations of AdPOD27 and AdPOD64 were analyzed, and the correlation between their expression and POD activity were also studied. The results showed that the length of open read frame of AdPOD27 and AdPOD64 was 984 and 957 bp, encoding 327 and 318 amino acids, respectively, which GenBank accession No.were MF774100 and MF774101. AdPOD27 and AdPOD64 were hydrophilic and alkaline proteins belonging to class Ⅲ of the plant heme-dependent peroxidase superfamily. The two proteins had signal peptide, transmembrane structure and phosphorylation sites. AdPOD27 and AdPOD64 located in mitochondrion and extracellular region, respectively. qRT-PCR analysis showed that the expression of AdPOD27 was up-regulated greatly treated with abscisic acid (ABA) and under 4℃, while AdPOD64 expression only enhanced treated with ABA. Moreover, the AdPOD27 expression had significant correlations with POD activity and AdPOD64 expression. Therefore, AdPOD27 and AdPOD64 would be involved in fruit softening, low temperature response and ABA induction of A. deliciosa.