金花茶查尔酮合成酶基因全长克隆与序列分析

Cloning and Sequence Analysis of Chalcone Synthase Gene cDNA from Camellia nitidissima

利用RT-PCR和RACE方法,从我国珍稀植物金花茶(Camellia nitidissima)花瓣中获得了查尔酮合成酶(chalconesynthase,CHS)基因的cDNA全长,命名为Cn-CHS,GenBank登录号HQ269804。碱基序列分析表明,Cn-CHS全长1 454bp,包含77 bp的5′非翻译区、207 bp的3′非翻译区和一个长为1 170 bp编码389个氨基酸的开放阅读框。氨基酸序列分析显示该基因编码的蛋白具有CHS家族保守存在的所有功能活性位点和特征性多肽序列。氨基酸序列比对分析表明,Cn-CHS与蔷薇科、杜鹃花科、茄科等植物的CHS相似性都在92%以上;与山茶科山茶属物种山茶(C.japonica)CHS完全一致;与茶(C.sinensis)CHS相似性达99%,有5个氨基酸位点存在差异,其中包括一个功能性位点。

A full-length cDNA sequence of chalcone synthase（CI-IS） gene was obtained from petals of Camellia nitidissima using RT-PCR and RACE,named Cn-CHS（ GenBank accession No. HQ269804. Sequence analysis indicated that Cn-CHS is 1 454 bp in full length and contains a 5 ＇-untranslated region （5＇-UTR）of 77 bp, a 3＇-UTR of 207 bp, and an opening reading frame （ORF）of 1 170 bp encoding a 389 predicted amino acids residues which possessed all the conserved active sites for the CHS function as well as the family special polypeptides. Sequence alignment of amino acids revealed that Cn-CHS shared more than 92% homology with CHS from plants of Rosaceae, Ericaceae, Solanaceae; 100% homology with Camellia japonica and 99% homology with Camellia sinesis, which possess five different sites including a function one compared with Camellia nitidissima CHS.