杜鹃红山茶ACO1的克隆及其表达分析研究

根据山茶（Camellia japonica）同源序列设计特异性引物,利用同源克隆和3°,5°-RACE技术,从杜鹃红山茶（C. azalea）花芽组织中克隆出ACC氧化酶（ACC-oxidase, ACO）基因,命名为CaACO1,基因全长1232 bp,开放阅读框963 bp,编码320个氨基酸。实时荧光定量PCR分析发现,ACO1在杜鹃红山茶不同组织中均得到表达,其中茎尖ACO1表达量最低,其次花芽、叶芽、根尖,表达量较高的是真叶和花器官,随着叶片成熟和花器官发育ACO1表达量均逐渐增加。结果表明,该基因可能参与杜鹃红山茶叶片发育,并且与花器官衰老密切相关。ACO1在参试的8个山茶品种花器官发育过程中的表达模式基本一致,但不同品种间的表达量存在差异。相关性分析发现ACO1表达量与花型、花色、花径和花瓣数4个形态指标均无显著相关性。

Cloning and Expression Analysis of ACO1 from Camellia azalea

On the basic of homologous sequences of Camellia japonica, an ACC-oxidase (ACO) gene was cloned from the floral bud of C. azalea by the 3°,5°-RACE technology named CaACO1. The full-length cDNA of CaACO1 was 1232 bp, containing a 963 bp ORF which encoding 320 amino acids. Expression of ACO1 in the four development periods of the floral organ in C. azalea were analyzed by fluorescent quantitative real-time PCR. ACO1 was expressed in twelve samples differently, where the expression level of ACO1 in shoot tip was the lowest, medium in flower bud, leaf bud and root tip, the highest in true leaves and flower, which indicated that ACO1 may be involved in the leaf development of C. azalea and associated with flower senescence. The trends of expressions of ACO1 were almost the same as in the four development periods of the eight camellias, but the expression levels were different. Correlation analysis found that the expression of ACO1 was not significantly correlated with four morphological indexes of flower type, flower color, flower diameter and petal number.