The roots of Glycyrrhiza uralensis are widely used in Chinese medicine for their action of clearing heat, detoxicating, relieving cough, dispelling sputum and tonifying spleen and stomach. The reason why Glycyrrhiza uralensis has potent and significant actions is that it contains various active secondary metabolites, especially glycyrrhizic acid. In the present study, we cloned the cDNA coding 3-hydroxy-3-methylglutary CoA reductase (HMGR) involved in glycyrrhizic acid biosynthesis in Glycyrrhiza uralensis. The corresponding cDNA was expressed in Escherichia coli as fusion proteins. Recombinant HMGR exhibited catalysis activity in reduction of HMG-CoA to mevalonic acid (MVA) just as HMGR isolated from other species. Because HMGR gene is very important in the biosynthesis of glycyrrhizic acid in Glycyrrhiza uralensis, this work is significant for further studies concerned with strengthening the efficacy of Glycyrrhiza uralensis by means of increasing glycyrrhizic acid content and exploring the biosynthesis of glycyrrhizic acid in vitro.

Objective:Stephania tetrandra is widely used in traditional Chinese medication.In present study,we studied the resource status of it in Anhui and Jiangxi Province.Methods:We inspected relevant documents to confirm which counties we would investigate;and then,we interviewed many relative local people and carried out sample-plot survey.Results:The resource of wild Stephania tetrandra in the two provinces were both seriously damaged.Conclusion:Large-scale promotion of artificial cultivation was required to ensure the supply and to realize the reasonable and sustainable utility of this medicinal material.

OBJECTIVETo clone and analysis the sequence of 3-hydroxy-3-methylglutary CoA reductase (HMGR) cDNA from Glycyrrhiza uralensis.

METHODThe primers were designed based on the conservative region of HMGR nucleic acids sequence from public database. The target gene was obtained from root of G. uralensis by use of homologous cDNA amplificati on and RACE technologies. The sequence alignment was performed using BLAST. The open reading frame was identified by use of the ORF Finder. The protein domains were defined by use of Prosite software. Clustal was used to conduct multiple amino acid sequence alignment and MEGA 5.0 was used to conduct the phylogenetic tree.

RESULTThe GuHMGR cDNA sequence was obtained contains 1 842 bp contains a 1 722 bp ORF, encoding 573 amino acids with 3-hydroxy-3-methylglutary CoA reductases family profile. Deduced amino acid sequence had 84% and 76% homology to the amino acid sequence of Pisum sativum, Medicago truncatula.

CONCLUSIONThe cloning of 3-hydroxy-3-methylglutary CoA reductase (HMGR) cDNA will provide a foundation for exploring the function of HMGR in glycyrrhizin biosynthesis.

Amino Acid Sequence ; Cloning, Molecular ; DNA, Complementary ; genetics ; Glycyrrhiza uralensis ; chemistry ; classification ; enzymology ; genetics ; Hydroxymethylglutaryl CoA Reductases ; chemistry ; genetics ; metabolism ; Molecular Sequence Data ; Phylogeny ; Plant Proteins ; chemistry ; genetics ; metabolism ; Sequence Alignment