Cloning and Expression Analysis of amp;iamp;RrGT2amp;/iamp; Gene Related to Anthocyanin Biosynthesis in amp;iamp;Rosa rugosaamp;/iamp;

摘要

At present, the research about flower color of Rosa rugosa is a very inno-vative and practical study. Glycosylation modification fulfills an important role in increasing the stability and solubility of anthocyanin in plants. In this study, based on the transcriptional database of R. rugosa , a gene with full length cDNA of 1422bp, encoding 473 amino acids, designated as RrGT2 , were isolated from flowers of R. rugosa ‘Zizhi’ and then functionally characterized. According to online software prediction, the molecular formula of the protein encoded by the RrGT2 gene is C_(2334)H_(3628)N_(602)O_(711)S_(18), the relative molecular mass is 52,075.17 Da, and the theoretical isoelectric point is pI = 4.76. The result of the RrGT2 protein 3D model construction showed that it had the highest homology with the UDP-glycosyltransferase 74F2 protein model in the database (39.53). Sequence alignments with the NCBI database showed that the RrGT2 protein is a member of the GTB superfamily. Homology analysis revealed that the coding regions of RrGT2 was highly specific among different species, but still had typical conserved amino acid residues called PSPG that are crucial for RrGT2 enzyme activity. RrGT2 transcripts were detected in five flowering stages and seven tissues of R. rugosa ‘Zizhi’, R. rugosa ‘Fenzizhi’ and R. rugosa ‘Baizizhi’, and their expression patterns corresponded with the accumulation of antho-cyanins. Therefore, we speculated that glycosylation of RrGT2 plays a crucial role in anthocyanin biosynthesis in R. rugosa .