光皮桦ACC氧化酶基因BlACO的克隆和表达分析

ACC（1-aminocyclopropane-1-carboxylic acid）氧化酶（ACO）是植物乙烯合成过程中的关键限速酶,对乙烯的合成具有重要的调控作用。以光皮桦茎叶组织提取的RNA为模板,据已报道的ACO同源序列设计简并引物,通过RT-PCR扩增获得部分基因片段,结合5＇,3＇RACE方法从光皮桦中扩增出1个ACO的全长cDNA序列。该基因cDNA全长1262bp,具有一个957bp的完整开放阅读框架,编码含318个氨基酸的蛋白。与其他植物中的ACO基因进行同源性比对的结果显示,BlACO蛋白与欧洲白桦的同源性最高,达到97%。该基因在光皮桦的雄花和雌花中表达量较高,而在茎中的表达量较低。

Cloning and Expression Analysis of ACC Oxidase Gene BlACO in Betula luminifera H.Winkl.

1-aminocyclopropane-1-carboxylic acid oxidase （ACO） is an important rate-limiting enzyme and plays a critical role in regulation of the ethylene biosynthesis. The BlACO gene was cloned by RT-PCR and 5＇,3＇ RACE methods,using mRNA template from stem and leaf of Betula luminifera,and the designed primers according to the homologous sequences of ACO from other species. Sequence analysis showed that BlACO cDNA was 1 262 bp length and contained a single open reading frame encoding a protein of 318 amino acids. The results of homology comparison showed that BlACO protein shared a 97% homology with Betula pendula. The expression of BlACO gene was higher in male flower and female flower of Betula luminifera,and lower in stem.