东方百合查尔酮异构酶基因LhCHI的克隆及表达

Cloning and Expression Analysis of Chalcone Isomerase Gene Lh CHI in Oriental Hybrid Lily(Lilium spp.)

利用RT-PCR结合RACE的方法从东方百合‘索邦’花被片中克隆了查尔酮异构酶(CHI)基因,命名为Lh CHI(Gen Bank登录号为KJ784468)。该基因开放阅读框702 bp,编码233个氨基酸,预测该蛋白相对分子质量25 KD,等电点(p I)为4.7。同源比对和系统进化分析表明,Lh CHI基因编码的氨基酸序列具有查尔酮异构酶典型的催化活性保守位点,与百合科郁金香(Tulipa fosteriana)查尔酮异构酶序列一致性为83.3%。半定量PCR和荧光实时定量PCR分析结果表明,Lh CHI基因在百合的根、茎、叶片、鳞茎、开放花被片、花药以及柱头中均有表达,花器官中相对表达量较高,花发育后期的柱头、花柱、花被片等组织中Lh CHI基因表达水平普遍高于花发育早期。

The gene LhCHI encoding chalcone isomerase （CHI） involved into flavonoids synthesis was cloned from inner tepals of Oriental hybrid lily ＇ Sorbonne＇ （ LhCHI, GenBank accession No. KJ784468 ）. The eDNA of LhCHI was obtained by RT-PCR and Rapid Amplification of eDNA Ends techniques. The open reading frame of LhCHI was 702 bp in length, enco- ding a protein polypeptide of 233 amino acids with a predicted molecular weight of 25 kD and a theoretical pI of 4.7. The deduced amino acid sequence of LhCHI shared 83.3% identity with CHI from Tulipafosteriana, and contained typical con- served catalytic chalcone elements. Quantitative real-time PCR analyzed the expression profiles of LhCHI in different tis- sues. IACH1 was constitutively expressed in root, stem, led, bulb, tepal, anther, style and stigma with particularly high expression in flowers. The expression level of LhCHI in later stage flowers is generally higher than that in the early stage flowers.