羊踯躅八氢番茄红素脱氢酶基因的克隆及表达分析

Cloning and Expression Analysis of PDS Gene from Rhododendron molle

旨在研究羊踯躅八氢番茄红素脱氢酶基因的功能,为其花瓣着色的分子机理研究提供一定的理论依据。以羊踯躅瓣为材料,采用RT-PCR和RACE方法从花瓣cDNA中克隆获得到2098 bp的八氢番茄红素脱氢酶基因cDNA序列,命名为RmPDS。序列分析表明,RmPDS基因包含一个长度为1743 bp编码580个氨基酸的开放阅读框。利用NCBI分析该基因的氨基酸序列,Blast序列分析结果显示RmPDS与其他植物PDS蛋白氨基酸的相似性达到87.80%。用MEGA软件构建系统进化树,结果显示羊踯躅PDS与茶树PDS蛋白的亲缘关系最近。荧光定量PCR检测结果表明RmPDS基因在羊踯躅花蕾期和膨大期表达量较低,在初花期表达量最高,盛花期表达量有所降低。RmPDS基因参与羊踯躅花色的形成,研究结果为进一步探究该基因在花色形成中的作用机制奠定基础,同时也为构建杜鹃VIGS体系提供报告基因。

We aim to study the function of PDS gene in Rhododendron molle, and provide a theoretical basis for studying the molecular mechanism of petal coloring. R. molle was used as material, a PDS gene was cloned from R. molle cDNA using RT-PCR and RACE methods. The full-length cDNA sequence of the PDS gene is 2098 bp, named RmPDS. The sequence analysis showed that the RmPDS contained a 1743 bp open reading frame encoding 580 amino acids. The homologous alignment showed that it shared 87.80% of amino acid identities with PDS from the other plant plants using NCBI blast tool. The phylogenetic tree constructed by MEGA software indicated that the genetic relationship between R. molle and Camellia sinensis was the most intimate. The results of real-time fluorescence quantitative PCR showed that the RmPDS gene expression level was lower in the bud stage and expansion stage, and reached to the highest level in the early flowering stage,but decreased in the blooming stage. RmPDS was involved in the formation of R. molle flower color. This study may provide references for further research on the molecular mechanism of RmPDS involved in the formation of R. molle flower color. Meanwhile, the study provides a reporter gene for the construction of the VIGS system in Rhododendorn.