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根据已知的甜瓜蛋白激酶类基因CmPKC的部分序列,设计带有酶切位点的引物,采用RT-PCR方法获得该基因的完整cDNA序列,并对其蛋白进行功能预测和理化性质分析;采用实时荧光定量PCR分析不同白粉病抗性材料、不同处理时间点该基因的表达量变化情况:将该基冈完整的ORF连接到原核表达载体pEASY-E1上,转化大肠杆菌(E.coli) BL21 (DE3),通过不同浓度IPTG诱导表达,获得适宜的诱导表达体系,SDS-PAGE检测表达产物.结果表明克隆获得的CmPKC基因长约为2 830 bp,开放阅读框为2 493 bp,编码831个氨基酸.生物信息学预测该蛋白的跨膜区域有4个信号肽;在甜瓜白粉病不同抗性材料上相对表达量变化趋势不同,在抗性材料上表达丰度出现的时间较感病材料早,且在不同材料上相对表达量变化趋势与已报道的一个甜瓜感病相关MLO家族基因一致,推测我们所获得的基因也可能与感病及开花、生长发育基因相关,且属于早期应答基因.该蛋白适宜的诱导体系是100 mg/mL IPTG诱导4h,原核表达产物与预期大小一致,表明该基因能够成功表达,为深入探索该基因的功能提供了研究依据.“,”In order to clone the protein kinase gene from Cucumis melon and analyse the prokaryotic expression,the primers were designed to based on the sequence which were obtained.The sequences of CmPKC were cloned from Cucumis melon L.by RT-PCR.The physical and chemical traits,secondary structure and three-dimensional structure of the CmPKC protein were forecasted and analyzed,and its structure and function were predicted.And the different expression levels of CmPKC gene in different time were analyzed by fluorescent quantitative PCR.And then the cloned opening reading frame of CmPKC gene was inserted into vector pEASY-E 1.The recombinant plasmid pEASY-E1-CmPKC was expressed in a prokaryotic expression system after they were transformed into E.coli BL21 (DE3).The fusion proteins were analyzed by SDS-PAGE.The eDNA contains a 2 493 bp opening reading frame and encodes a predicted protein of 831 amino acids.Transmembrane regions and four signal peptide were presented in CmPKC.Relative real-time PCR analysis indicated that CmPKC showed the highest transcript abundance in resistance material earlier than susceptibility material,and the expression trend in different material was same to CmMLO2 which were indicated related to susceptibility traits.The gene we obtained might to related to susceptibility traits,and it was an early response genes.The CmPKC gene was expressed in a prokaryotic expression system,and it provide a scientific basis for functional genomics research of Cucumis melon L.and mechanism research of flavonoids biosynthesis.