柿果实ACC氧化酶cDNA的克隆及其序列分析

Cloning and Sequence Analysis of cDNA Encoding ACC Oxidase from Persimmon Fruit

以柿 (DiospyroskakiThunb .)果实为材料 ,根据其它植物ACC氧化酶 (1 aminocyclopropane 1 carboxylicacidoxidase ,ACO)氨基酸保守区 ,设计 1组简并引物 ,通过RT PCR法扩增出 2个约 80 0bp大小的cDNA片段。将其克隆至pGEM T载体上 ,对这 2个重组克隆进行序列测定 ,DK ACO1由 834个碱基组成 ,编码 2 5 9个氨基酸 ;DK ACO2为836个碱基 ,编码 2 6 0个氨基酸。它们均具有其它植物ACC氧化酶中存在的保守区 ,且在多肽水平上的同源性很高 ,与番茄LE ACO1的同源性DK ACO1是 86 .2 % ,DK ACO2是 82 .5 % ;与甜瓜CM ACO1的同源性DK ACO1是82 .6 % ,DK ACO2为 81.1%。

The cDNA encoding ACC oxidase in persimmon ( Diospyros kaki Thunb.) fruit was cloned and its sequence was analyzed. According to the conserved acid sequence for ACC oxidase in other plant, we designed a group of oligonucleotide primers. Using RT PCR method, two cDNA fragments about 800 base pair were amplified and then cloned into pGEM T vector. The sequence determination was performed on the two fragments, the result suggested that DK ACO1 was composed of 834 base pair and encoded 259 amino acid. DK ACO2 was composed of 836 base pair encoding 260 base pair. Each of the cloned cDNA fragment in persimmon fruit had the same conserved amino acid sequences for ACC oxidase as that in other plants, and they had higly homology at polypetide level. Their homology percentage of DK ACO1, DK ACO2 were 86.2% , 82.5% respectively comparing with LE ACO1 from tomato fruit. While comparing with CM ACO1 from melon, their homology percentage of DK ACO1, DK ACO2 were 82.6%, 81% respectively.