春兰CgSEP3基因的克隆和表达分析

Cloning and Expression Analysis of CgSEP3 Gene fromCymbidium goeringii

该研究采用RT PCR和RACE技术从春兰（Cymbidium goeringii）中分离到1个SEPALLATA3（SEP3）基因.序列分析表明,该基因含有1个732 bp的开放阅读框（ORF）,共编码243个氨基酸.系统进化树分析显示,该基因是MADS-box基因家族AP1/AGL9组SEP的同源基因,其编码蛋白与其它植物SEP3类蛋白具有较高的一致性,命名为CgSEP3（登录号为KF924272）.实时荧光定量分析表明,CgSEP3在春兰花器官中均有表达,其中在唇瓣、侧瓣和萼片中的表达量较高,在子房和蕊柱中的表达量较低;而且CgSEP3在花发育各个时期都有表达,在1～2 cm的花芽中表达量最高,在盛开的花中的表达量最低.研究认为,CgSEP3基因可能在春兰花瓣和萼片的形成过程中具有重要作用.

In this research,a novel SEP3 gene,named CgSEP3（GenBank accession number KF924272）,was isolated from Cymbidium goeringii by RT PCR and RACE PCR techniques.Sequence analysis showed that this gene contains an open reading frame of 732 bp encoding a putative protein of 243 amino acids.The de duced protein showed high identity with other SEP3 proteins from different species,phylogenetic tree anal ysis also indicated that CgSEP3 belongs to SEP clade of AP1/AGL9 subfamily.Real-time quantitative PCR demonstrated that CgSEP3 was expressed in all flower organs,highly expressed in lips,lateral petals and sepals,and the lowest in young ovary and columns.In addition,CgSEP3 was expressed in different devel opment stages of flower,with the highest expression in flower buds （1-2 cm）,and the lowest in opened flower.These results displayed that CgSEP3 may regulate the petals and sepals formation of C.goeringii.