The Gene Cloning And Basic Research Of MYB Transcription Factors In Dendrobium

Dendrobium species are epiphytic plants of Orchidaceae and traditionally precious Chinese medical herbals. But there are rarely reports of gene cloning and functional research of this species all over the world. The cloning of useful gene is the basis of the whole genetic engeering and research of molecular biology. In the research of medicinal Dendrobium, cloning the useful genes, which combined with the transgenic technology, could improve the yield and quality of the Dendrobium.In this study some cDNA sequences were chosen from our laboratory cDNA library and the TAIL-PCR technology was used to amplify the full length of gene which has the complete ORF. A total of three genes have been amplified. Two were MYB genes, and one is EREB gene. And all the cloning vectors and expression vectors were constructed. One MYB gene were chosen and named DnMYB1. It was studied with the bioinformatic analysis and Real Time-qPCR for verification of its function.The Gateway cloning methods was used to construct the cloning vectors and expression vetors. The method of floral dip was used to make sure that the gene DnMYB1could turn into the wild type Arabidopsis thaliana. Then the phenotype and genotype of the transgenic plants were observed. Overexpression of plants has fewer trichomes than wild types and even disappear. The RNAi plants has the same phenotype with the overexpression plants. At the seedling stage the plants has few trichomes and disappear when growed up. So we infer that this transcription factor is related to the morphogenesis of trichome; this transcription factor has the highly conserved domans with other MYB transcriptions. In the last, the Real-time Quantitative PCR technology were used to check and analyze the gene expression of wild Arabidopsis thaliana and transgenic Arabidopsis. Finally conclusion is reached that the DnMYB1transcription factor has the function of regulate and control the form and maturation of the trichome, which is a negative regulator of the form of plant epidermal trichome.