冬枣过氧化氢酶基因的克隆及表达分析

从冬枣半红期和全红期果实的SSH文库中筛选得到与桃树CAT1基因相似性高达88%的基因片段。根据该基因片段设计特异性引物,通过5′和3′-RACE扩增,拼接得到1 586bp序列,该序列包含了1 479bp的完整开放阅读框,编码492个氨基酸,具有CAT基因家族的保守功能域,命名为ZjCAT,GenBank登录号为JN831452。氨基酸序列分析表明,ZjCAT与桃树、陆地棉等多种植物的过氧化氢酶有很高的相似性,并属于类型Ⅲ过氧化氢酶。实时PCR分析结果显示,ZjCAT基因在冬枣不同组织和果实成熟期差异性表达,其中在冬枣半红期果实中表达量最高。表明ZjCAT基因在冬枣果实成熟衰老过程中可能具有重要的调控作用。

Cloning and Tissue Expression Analysis of Catalase Gene in Dongzao (Ziziphus jujuba)

The gene fragment homologous with peach CAT1 gene up to 88%,was obtained from the SSH libraries of Dongzao(Ziziphus jujuba cv Dongzao) half-red and red fruit.Based on the fragment,specific primers were designed for 5′-and 3′-RACE amplification resulted in a sequence of 1 586,which contains a 1 479 bp complete open reading frame and encodes 492 amino acids,with a conserved functional domain of CAT gene family.It was named ZjCAT,with GenBank accession number JN831452.Amino acid sequence analysis indicated that,ZjCAT was high identity with the catalases of Prunus persica,Gossypium hirsutum and many other plants,and it belonged to the class Ⅲ.The results of real-time PCR showed that the gene differentially expressed in different tissues and at different fruit maturity stages,of which the expression in half-red stage was the highest,indicating its possible important roles in regulating the senescence of Dongzao fruit.