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利用RACE 技术从忽地笑(Lycoris aurea (L'Hér.) Herb.)花葶中克隆获得细胞色素P450 酶98A 亚家族蛋白编码基因LaCYP98A.该基因cDNA 全长1 794 bp,开放阅读框为1 518 bp,编码含有505 个氨基酸残基的LaCYP98A 蛋白.LaCYP98A 具有细胞色素P450 酶特征性的亚铁血红素结合结构域和半胱氨酸残基组成的活性中心.LaCYP98A 与拟南芥、大豆等其他植物CYP98A 氨基酸序列的一致性在60％以上,且具有CYP450 的所有特征模序.LaCYP98A 定位于植物细胞的内质网,其N- 端29 个氨基酸对于其亚细胞定位具有重要的作用.利用pET 表达系统,通过截掉其N- 端内质网定位区域,可以实现LaCYP98A 在大肠杆菌中的诱导表达.本研究为LaCYP98A 的功能鉴定和植物细胞色素P450 的原核表达及其催化的次级代谢产物的异源合成奠定了基础.“,”In this study,a gene encoding cytochrome P450 98A subfamily was cloned from the scape of Lycoris aurea (L'Hér.) Herb.,which was named as LaCYP98A.The full-length cDNA of LaCYP98A is 1794 bp with a 1518 bp open reading frame,encoding a deduced polypeptide of 505 amino acids.LaCYP98A protein contains cytochrome P450 typical active center domains consisting of heme-binding motif and cysteine.LaCYP98A shares more than 60％ identity with CYP98A from Arabidopsis thaliana,Glycine max and other plants,and owns all the motifs of CYP450.LaCYP98A protein was located in the endoplasmic reticulum,and the N-terminal 29 amino acids was of importance to the subcellular localization of LaCYP98A.Based on the pET expression system,LaCYP98A was successfully expressed in Escherichia coli via truncating N-terminal localization region.In this study,molecular cloning and expression analysis of Lycoris aurea CYP98A were investigated to facilitate further research in functional characterization and prokaryotic expression of plant CYP450 as well as plant secondary metabolites biosynthesis in E.coli.