铁皮石斛SEP基因克隆与表达的研究

Cloning and Expression Analysis of SEP Gene in Dendrobium candidum

随着植物中越来越多的MADS-box基因被克隆出来,对经典的ABC模型进一步进行完善,提出花发育的ABCE“四元体模型”,其中SEP1、SEP2、SEP3、SEP4为E类基因,SEP1同源基因在花器官识别方面起着重要的作用。本研究以铁皮石斛花器官作为实验材料,用RACE方法快速克隆全长cDNA,生物信息学分析全长cDNA为926 bp,具有完整的开放阅读框(ORF)681 bp,具有227个氨基酸,分离出SEP-A同源基因,另外SEP-B同源基因全长cDNA为954 bp,具有完整的开放阅读框(ORF)774 bp,编码243个氨基酸。在各个花器官中进行RT-PCR,发现SEP-A基因在合蕊柱和唇瓣中表达,而SEP-B基因在唇瓣、花萼和幼叶中表达。

As more and more MADS-box genes have been cloned in plants,the classical ABC model has been further improved,and the ABCE“Quaternary Model”of flower development has been proposed.Among them,SEP1,SEP2,SEP3 and SEP4 belong to class E gene,and the SEP1 homologous gene plays an important role in flower organ recognition.In this study,the full-length cDNA of Dendrobium candidum SEP gene was cloned rapidly by RACE method.Bioinformatics analysis showed that the full-length cDNA was 926 bp,with a complete open reading frame(ORF)of 681 bp and SEP protein containing 227 amino acids,and the SEP-A homologous gene was isolated.Additionally,the full-length cDNA of SEP-B homologous gene was 954 bp,with a complete open reading frame(ORF)of 774 bp,encoding 243 amino acids.The results of RT-PCR in various floral organs showed that the SEP-A gene was expressed in the gynostemium and labellum while the SEP-B gene was expressed in the labellum,calyx and young leaves.