Cloning and characterization of a β-amyrin synthase gene from the medicinal  tree Aralia elata (Araliaceae).
Aralia elata is an important medicinal plant in China; it produces  large amounts of oleanane type triterpene saponins. A full-length cDNA encoding β-amyrin  synthase (designated as AeAS) was isolated from young leaves of A.  elata by reverse transcription-PCR. The full-length cDNA of AeAS was  found to have a 2292-bp open reading frame, encoding a protein with 763 amino  acid residues. The deduced amino acid sequence of AeAS showed the highest  identity (97%) to Panax ginseng β-amyrin synthase. When AeAS cDNA  was expressed in Escherichia coli, an 87.8-kDa recombinant protein was  detected by SDS-PAGE and Western blotting. The sequence was also heterologously  expressed in the yeast Pichia pastoris, and production of β-amyrin was detected by HPLC. Tissue  expression pattern analysis by real-time reverse transcription-PCR revealed  that AeAS is strongly expressed in leaves and stems, and weakly  expressed in roots and flowers.
College of Plant Science, Jilin University, Changchun, China.
Y
Y
Wu
H D
HD
Zou
H
H
Cheng
C Y
CY
Zhao
L F
LF
Sun
S Z
SZ
Su
S P
SP
Li
Y P
YP
Yuan
D000595:Amino Acid Sequence; D027983:Aralia / Q000201:enzymology* / Q000235:genetics*; D001483:Base Sequence; D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics*; D019751:Intramolecular Transferases / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D010946:Plants, Medicinal / Q000201:enzymology* / Q000235:genetics*; D012503:Saponins / Q000096:biosynthesis; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014197:Trees / Q000201:enzymology* / Q000235:genetics; D014315:Triterpenes / Q000378:metabolism
D018076:DNA, Complementary; D012503:Saponins; D014315:Triterpenes; D019751:Intramolecular Transferases; C039924:2,3-oxidosqualene-beta-amyrin-cyclase