Cloning and Expression Analysis of Chalcone Isomerase Gene from Narcissus tazetta var.chinensis
Chalcone isomerase(CHI)is one of the key enzymes in the biosynthesis pathway of flavonoids and plays an important role in the process of flower color development.Three genes,named NtCHIW,NtCHIJ and NtCHIY respectively,were cloned from Narcissus tazetta var.chinensis petal by RT-PCR and RACE.The open reading frame encompassed 735 bp encoding a polypeptide of 244 amino acids.Sequencing analysis showed that the amino acid sequence of Baihua Narcissus was 93.03%,93.44%,64.75%,55.42%,50.58%,59.43%,and 58.20% homologous with CHI genes from Jinzhanyintai Narcissus,Huanghua Narcissus,Allium cepa,Elaeis oleifera,Vitis labrusca,Oryza sativa Japonica,Arabidopsis thaliana,respectively.The result of real time RT-PCR showed that the transcription expression of CHI gene changed accordingly during flower blooming,indicating the possible role of CHI genes in the change of flower color.