摘要
以荔枝品种妃子笑果实的cDNA为模板 ,设计膨大素的简并引物 ,进行RT PCR。得到的扩增产物经纯化后与pGEM T Easy载体连接 ,转化大肠杆菌。任意挑选阳性克隆 ,进行序列分析 ,得到 2个序列不同的膨大素基因片段 ,分别命名为Lc Exp1和Lc Exp2。这 2个基因片段中均存在膨大素基因的保守区域 ,即 8个半胱氨酸残基和 3个色氨酸残基。Lc Exp1和Lc Exp2分别编码 177和 179个氨基酸 ,2者间的碱基同源性为 71.6% ,氨基酸同源性为76.3 %。在氨基酸水平上 ,Lc Exp1与Fa Exp2、Pp Exp1的同源性分别为 92 .7%和 92 .1% ,而Lc Exp2与Fa Exp2、Pp Exp1的同源性仅为 77.4%和 76.3 %。
Using PCR degenerate primers designed with reference t o the conserved amino acid sequences of known expansins to amplify cDNA fragment s in litchi fruits by RT-PCR, two different cDNA fragments, named Lc-Exp1 and Lc-Exp2, were c loned. Lc-Exp1 and Lc-Exp2 was respectively composed of 531 bp and 537 bp, encoding 177 and 17 9 amino acids, respectively. Eight cysteine residues and 3 tryptophan residues, which are supposed to be the characteristics of expansins, are conserved in both Lc-Exp1 and Lc-Exp2. In addition, the homology between two expansins is 71.6% at nucleot ide acid sequence level and 76.3% at amino acid sequence level. The homology be tween Lc-Exp1 and Fa-Exp2 and Pp-Exp1 is 92.7% and 92.1%, b ut that of Lc-Exp2 and Fa-Exp2 and Pp-Exp1 is only 77.4% and 76.3% at amino acid sequence level, respectively.
出处
《中国农业科学》
CAS
CSCD
北大核心
2003年第12期1525-1529,共5页
Scientia Agricultura Sinica
基金
教育部留学回国人员基金资助项目(2 0 0 34 0 6)
关键词
荔枝
果实
膨大素基因
克隆
序列分析
Litchi chinensis Sonn.
Expansin
cDNA cloning
Sequence analysis
