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.