[Full-length cDNA cloning and bioinformatics analysis of PnUGT1 gene in Panax notoginseng]

After searching the transcriptome dataset of Panax notoginseng, one unique sequence Pn02086 encoding UDP-glucosyltransferase (UGT), which may be involved in triterpene saponin biosynthesis, was discovered. The open reading frame of the UGT gene, named as PnUGT1, was cloned by 5'-RACE and RT-PCR method from P. notoginseng. The GenBank accession number for this gene is JX018210. The bioinformatic analysis of this gene and its corresponding protein was performed. The PnUGT1 gene contains a 1488 bp open reading frame and encodes a predicted protein of 495 amino acids. The molecular weight is 55.453 kD and the protein is unstable. In the secondary structure, the percentage of alpha helix, beta turn, random coil were 36.16%, 11.31%, 52.53%, respectively. The PnUGT1 contains 7 conserved domains predicted by InterProScan, including PSPG-box which is a unique consensus sequence of glycosyltransferases involved in plant secondary metabolism. The PnUGT1 was most likely to be located in the cytoplasm, without signal peptide and transmembrane region. Sequence alignment and phylogenetic analysis demonstrated that PnUGT1 had relative close relationship to the triterpene UDP-glucosyltransferase of Medicago truncatula (AAW56092), with the 66% similarity of conserved domain PSPG-box. PnUGT1 was more abundant in P. notoginseng leaf than in flower, stem and root. Therefore, PnUGT1 gene may be involved in notoginsenoside biosynthesis.