苹果属观赏海棠McCHI基因的克隆及不同叶色品种间表达差异分析

Cloning of McCHI Gene of Malus Crabapple and Its Expression Analysis in the Cultivars with Different Type Foliar Color

以苹果属观赏海棠品种‘王族’叶片提取的总RNA为模板,通过RT-PCR与RACE扩增,获得1条660bp的查尔酮异构酶(CHI)基因的全长cDNA序列,编码219个氨基酸,命名为McCHI。该基因DNA序列全长1180bp,由3个内含子和4个外显子组成,具有CHI基因的典型结构。采用实时荧光定量PCR和紫外可见光分光光度计法,对3类不同叶色类型的观赏海棠品种‘火焰’(绿色类叶片)、‘绚丽’(新叶有色类红色叶片)、‘高原之火’(新叶有色类红色叶片)和‘王族’(常色叶类紫色叶片)幼叶和功能叶中的McCHI表达及其花色苷含量进行测定分析,结果表明:McCHI在4个品种的幼叶和功能叶中均有表达,其表达量与花色苷积累随品种不同和叶龄不同表现出明显差异。

With the total RNA from leaves of Malus crabapple ‘Royalty’as the template,a full cDNA of CHI（chalcone isomerase） gene（660 bp） was cloned by reverse transcription polymerase chain reaction（RT-PCR） and rapidamplification of cDNA ends（RACE） . The gene was named McCHI,encoding a protein of 219 amino acids. The corresponding DNA sequence is 1 180 bp,containing 3 introns and 4 exons,and has a typical structure of CHI gene. The expression of McCHI and the content of anthocyanin were determined by real-time quantitative PCR and spectrophotometer respectively in the mature and young leaves of M.‘Flame’（green young and mature leaf） ,M.‘Radiant’（red young leaf and green mature leaf） ,M.‘Prairifire’（red young leaf and green mature leaf） ,M.‘Royalty’（purple young and mature leaf） . The results showed that McCHI was expressed in both mature leaves and young leaves of the above four cultivars,but the expression levels was greatly different at different leaf ages and between cultivars.