目的在对长柄石杉Huperzia serrata、闽浙马尾杉Phlegariurus minchegensis、华南马尾杉Phlegariurus austrosinicus和有柄马尾杉Phlegariurus petiolatus 4种石杉科植物的L-赖氨酸脱羧酶(L-lysine decarboxylase,LDC)基因编码区进行克隆的基础上,对长柄石杉的LDC基因全长序列进行分析并预测其蛋白结构。方法采用RT-PCR技术,以石杉科植物叶片提取的总RNA为模板克隆得到LDC基因编码区序列,通过BLAST比对和MEGA5.0软件对克隆的序列进行分析。采用RACE技术获得石杉科广布种长柄石杉的LDC基因全长序列,并对其蛋白的二级结构及三维结构进行预测分析。结果克隆的4种石杉科植物LDC基因序列与数据库中被注释为编码LDC的基因序列保持高度的相似性,长柄石杉LDC蛋白与NCBI中的蛇足石杉LDC氨基酸序列相似度很高,与蕨类植物江南卷柏的同源性也较高。长柄石杉LDC基因编码区全长为1 266 bp,编码403个氨基酸,Gen Bank登录号KF040056。结论克隆得到4种石杉科植物的LDC基因,分析了长柄石杉LDC基因的全长序列并预测其蛋白结构,为进一步阐明石杉科植物石杉碱甲生物合成途径奠定基础。 Objective To investigate the effects of L-lysine decarboxylase (LDC) on four species of Huperzia serrata, Phlegariurus minchegensis from Fujian and Zhejiang, Phlegariurus austrosinicus from Southern China and Phlegariurus petiolatus, ) Gene was cloned based on the full-length LDC gene sequence analysis and prediction of its protein structure. Methods The coding region of LDC gene was cloned by RT-PCR using the total RNA extracted from the leaves of Huperziaceae as a template. The sequence of the cloned gene was analyzed by BLAST and MEGA5.0 software. The RACE technique was used to obtain the full-length sequence of LDC gene from the genus Huperziaceae, and its secondary structure and three-dimensional structure were predicted. Results The sequences of the LDC genes of the four species of Huperziaceae cloned were highly similar to the sequences of the genes encoding LDCs in the database. The LDC protein of Haematophagoides pallens was highly similar to the LDC amino acid sequence of Huperzia serrata in NCBI, It has higher homology with fern Gangnam Selaginella. The coding region of LDC gene of Haliotis discus hannai was 1 266 bp in length, encoding 403 amino acids. The GenBank accession number was KF040056. Conclusion The LDC gene of four species of Huperziaceae was cloned and the full-length sequence of LDC gene was predicted and its protein structure was predicted. This study laid the foundation for further elucidation of Huperzine A biosynthesis pathway.