柿果实扩张蛋白基因cDNA克隆及原核表达

以‘富平尖柿’（Diospyros kaki L.‘Fuping Jianshi’）果实不同发育时期提取的总RNA为模板，利用RT-PCR结合RACE技术扩增得到5个扩张蛋白基因：成熟期CDK-Exp3（1 168 bp），转色期CDK-Exp4（1 120 bp）和CDK-Exp5（1 018 bp），膨大期CDK-Exp6（1 129 bp）和CDK-Exp7（1 121 bp）；5个基因的开放阅读框（ORF）均为765 bp，编码254个氨基酸；构建了CDK-Exp3原核表达载体pET-CDK-Exp3，并转化于E.coli BL21（DE3），SDS-PAGE检测结果显示表达了一个约43 kD的蛋白。

Cloning and Prokaryotic Expression of Expansin cDNA in Persimmon Fruits

Using the total RNA from different stages of persimmon（Diospyros kaki L.‘Fuping Jianshi’）fruit as the template，five expansin cDNA：CDK-Exp3（1 168 bp）from mature stage，CDK-Exp4（1 120 bp）and CDK-Exp5（1 018 bp）from colour-changed stage，CDK-Exp6（1 129 bp）and CDK-Exp7（1 121 bp）from fruit expanding stage were isolated by RT-PCR and RACE. The open reading frame of the five genes was 765 bp and encoded a protein of 254 amino acid residues. The CDK-Exp3 was cloned into pET-32a（+）vector to construct recombination prokaryotic expression vector pET-CDK-Exp3，and which was transformed to E.coli BL21. Recombinant protein about 43 kD was expressed in pET-CDK- Exp3 system and separated by SDS-PAGE electrophoresis.