玉米catalase-3基因克隆及低温表达研究

Molecular Cloning and Chilling Expression of Maize Catalase-3 Gene

应用RT-PCR技术,从玉米自交系承18经14℃冷锻炼处理的芽鞘中扩增出长1491 bp的Cat3全长cDNA。以pGEM-T Easy为载体,克隆了扩增片段,经酶切鉴定和DNA序列测定,确认为玉米Cat3基因。序列分析结果表明,该序列与GenBank中accession number:L05934的序列仅在两个核苷酸位点存在差异。同时采用Northern杂交方法对Cat3在不同低温处理的玉米芽鞘中的表达特性进行了研究,结果显示Cat3在经14℃冷锻炼处理的芽鞘中表达增强,表明该基因受低温的诱导表达,为玉米抗寒基因,对提高玉米的抗寒力起积极作用。

The full-length 1491-base-pair cDNA of catalase-3 were cloned from seedlings acclimated at 14℃ of maize inbred cheng 18 by reverse transcription-polymerase chain reaction （RT- PCR）. The fragment was inserted into pGEM - T Easy vector, and identified by endonuclease and DNA sequencing. It is affirmed that the fragment was catalase gene of maize. The results of sequence aligned in GenBank （accession number： L05934） show that two bases changed. At the same time the northern hybridization analysis of Cat3 are made with maize seedlings treated by different temperature. The resuits show that the transcription of Cat3 increased at 14 ℃ （acclimation period）. Cat3 was chilling resistant related gene, the expression of it was enhanced under the condition of chilling-acclimation and chilling stress. It plays positive roles in chilling resistant.