百脉根S-腺苷甲硫氨酸脱羧酶基因克隆与表达分析  

Cloning and Expression Analysis of S-adenosylmethionine Decarboxylase Gene from Lotus corniculatus L.

作　　者：路玉兰[1] 孙艳香[1] 冯雪[1] 赵学良[1] 

机构地区：[1]廊坊师范学院生命科学学院遗传与育种研究所,河北廊坊065000

出　　处：《华北农学报》2013年第2期78-85,共8页Acta Agriculturae Boreali-Sinica

基　　金：廊坊师范学院博士专项基金资助项目(LSZB200903)

摘　　要：S-腺苷甲硫氨酸脱羧酶(SAMDC;EC 4.1.1.50)是多胺合成过程中的限速酶。以日本百脉根EST序列为基础,通过设计特异引物进行RT-PCR扩增,获得了S-腺苷甲硫氨酸脱羧酶编码cDNA,命名为LcSAMDC1。LcSAMDC1基因组序列全长2 626 bp,存在3个内含子;cDNA序列全长1 799 bp,存在3个植物SAMDC基因特征性ORF,其中tORF编码2个氨基酸残基,sORF编码55个氨基酸残基,mORF编码354个氨基酸残基;mORF编码产物推断的分子量为38.6 kDa,具有2个高度保守的功能结构域(酶原剪切位点和PEST结构域);半定量RT-PCR分析显示,LcSAM-DC1在幼叶和根中具有高水平的表达,在茎中表达水平较低,而在成熟叶片中不表达。S-adenosylmethionine decarboxylase（SAMDC;EC 4.1.1.50）is a key rate-limiting enzyme located in the polyamine biosynthesis pathway.According to the sequence information of EST from Lotus corniculatus var.japonicus Regel,a cDNA of SAMDC was cloned from Lotus corniculatus,and named LcSAMDC1.The full-length genome sequence of LcSAMDC1 was 2 626 bp,including 3 introns.The full-length cDNA sequence of LcSAMDC1 was 1 799 bp,with 3 characteristic ORFs,which were tORF,sORF and mORF,coding 2,55,354 amino acid residues respectively.The deducted protein of mORF was with 38.6 kDa molecular weight,and had two highly conserved function domains（proenzyme cleavage site and PEST domain）.Semi-quantitative RT-PCR analysis showed that,the expression of LcSAMDC1 was higher in young leaves and roots than in stems,but failed to be detected in mature leaves.

关 键 词：百脉根 多胺 S-腺苷甲硫氨酸脱羧酶 LcSAMDC1 

分 类 号：Q78[生物学—分子生物学]