龙眼漆酶基因(DlLac)的克隆及表达分析

摘要

以‘石硖’龙眼为试材,采用RT-PCR结合RACE技术成功克隆一个龙眼漆酶基因全长cDNA序列,命名为DlLac,NCBI登录号为KY051551.DlLac基因序列全长1898 bp,编码576个氨基酸,NCBI比对结果显示其与荔枝漆酶氨基酸序列同源性最高,高达94％;进化树结果显示龙眼漆酶氨基酸序列与荔枝漆酶氨基酸序列具有高度同源性.氨基酸保守序列结果表明龙眼漆酶氨基酸序列含有漆酶的3个典型保守结构域,分别为:Cu-oxidase-3、Cu-oxidase和Cu-oxidase-2.结合龙眼果实在常温、低温贮藏条件下,果皮褐变与DlLac的表达关系,推测DlLac的上调表达可能对龙眼果皮褐变起促进作用.%In the present study,laccase gene cDNA was cloned and sequenced from ‘ shixia’ longan cultivar using RT-PCR and RACE,which was named as DlLac.The NCBI numbers were KY051551.The DlLac gene consists of 1898 bp encoding a polypeptide of 576 amino acids.DlLac gene had the highest homology with the Litchi chinensis (94％)through the NCBI blastn.Amino acids of laccase gene sequence had 3 highly conservative domain structure:Cu-oxidase-3,Cu-oxidase and Cu-oxidase-2.During the normal and cold storage,combining the relationship of pericarp browning and DlLac expression,it suggested that the laccase gene in pericarp may contribute to the postharvest longan pericarp browning.