Function Identification Of Vernalization-Ralated Gene Bra028171 In Chinese Cabbage

Venalization plays a vital role in folowering in Chinese cabbage[Brassica campestris L.ssp.pekinensis(Lour.)Olsson].Chinese cabbagge will turn from vegetative growth to reproductive growth when induced by low temperature then to flowering. There are plenty of genes taking part in the venalization stage which regulate the flowering stage. Bra028171 explored in this experiment is from the former research in our lab which changed in the expression level when Chinese cabbage vernailized. Bra028171 is located on the fourth chromosome which is 786 bp long and composed by 261 amino acids and is a conserved sequence. There is a homologous gene in Arabidopsis thaliana which is At5g38320 same as Bra028171, unknown function. In this study, we cloned the gene and studied its subcellular localization. We have explore the expression pattern of this gene and construct the super expression and RNAi vector and transform to the model plant Arabidopsis thaliana to analyze the function of this gene. And then exploring function of the gene in Chinese cabbage during the VERNALIZATION PROCESS. To provide reference for flowering of Chinese cabbage, and provide a theoretical basis for the prevention of premature bolting of Chinese cabbage.Test results are summarized as follows:(1)Through the sequence analysis of Bra028171, we found that there is a homologous gene At5g38320 gene in Arabidopsis thaliana which is also an unknown gene. We got some results by analyzing the biological information of Bra028171. The length of Bra028171 is 768, the length of the protein is 261, the predicted isoelectric point is 5.55, and the three-dimensional structure of the protein encoded by this gene is predicted by online tools.(2)Through the q PCR analysis of of Bra028171, we found that the expression of the gene was highest in stem, especially in flowering stage, and the expression of stem was significantly larger than that of other parts.(3) Through the analysis of the subcellular localization of Bra028171, Bra028171 was found to locate in the nucleus.(4) Over expression vector and RNAi interference vector were successfully constructed and imported into Arabidopsis thaliana.(5) PCR identification were performed to the resistant plants. After identification, 12 of 22 overexpression strains were positive strains, 9 of 16 RNAi strains were positive strains, the positive rates were 55%h and 56%, respectively.(6) Phenotypic investigation were perform to the transgenic Arabidopsis, we found that overexpression plants have longer stem and early flowering time than the RNAi plants. It showed that the gene had a promoting effect on flowering, and lack of the gene would cause delayed flowering.