Thirty-seven Squalene Synthase Gene And Its Function, A Preliminary Study

Object: The cDNA encoding Squalene Synthase and glyceroldehyde-s-3- phosphate dehydrogenase from Panax notoginseng (Burk.) F. H. Chen was cloned and sequenced. This work made it possible to analysis the function of SS gene on transcription level.Methods: we improved the previous method of total RNA isolation. The full- length cDNA of SS gene and the partial cDNA of GAPDH gene were obtained by RT-PCR, then cloned into pMD-18T Vector and sequenced. Results: With the modified Guanidine Thiocyanate method, high-quality and good-integrality total RNA was achieved and the cost time period for the isolation of RNA was sharply shortened. The analysis results indicated that the full-length cDNA of SS gene had 1270 bp with an open reading frame encoding 415 amino acids of protein.The SS sequence had 98%,89%,81%,78%,71% amino acid sequence homology and 98%,88%,77%,73%,66% nucleotide sequence homology to the SS gene sequence of Panax ginseng, Centella asiatica, Artemisia annua, Arabidopsis thaliana, Oryza sativa, respectively. The partial cDNA of GAPDH gene had 627 bp with an open reading frame encoding 209 amino acids of protein. The GAPDH sequence had 91%,93%,95% amino acid sequence homology and 82%,84%,85% nucleotide sequence homology to the GAPDH gene sequence of Arabidopsis thaliana, Tobacco, Panax ginseng, respectively.Conclussion: We isolated and reported the SS gene and GAPDH gene of Panax notoginseng to the GenBank firstly.