桃多聚半乳糖醛酸酶基因的cDNA克隆及序列分析

Cloning and Sequencing of cDNA of Polygalacturonase in Peach

以白粉桃成熟果实为材料,用Trizol法提取桃总RNA,根据已发表的多聚半乳糖醛酸酶(PG)基因的序列设计合成一对特异引物,经RT-PCR扩增出一条1 188 bp的目的片段,包括一个393个氨基酸组成的开放阅读框。通过TA克隆,把它连接到pGEM-Tvector上。PCR、酶切鉴定后进行基因测序,结果表明所克隆的PG基因与GenBank中肥城桃PG基因序列(AF095577)同源性为98.65%,相应的氨基酸的同源性为97.46%,说明此片段为桃PG基因片段。

Total RNA was extracted from mature fruits of Baifen peach by Trizol method. By using the specific primers designed from the PG gene in GenBank, a fragment about 1 188 bp with an open reading frame of 393 amino acids was produced by RT- PCR. The amplified fragment was cloned into pGEM-T vector and was identified by sequence analysis after PCR and restriction enzyme. The cDNA nucleotide sequence and deduced amino acid sequence were highly homologous to the reported peach PG cDNA. Thus, this fragment was proved as PG gene fragments of Peach.