Cloning and sequence analysis of squalene epoxidase gene from Inonotus baumii / 中草药

ABSTRACT

Objective: To clone the full-length cDNA encoding squalene epoxidase (SE), which is the key enzyme involved in the triterpenoid biosynthesis pathway in Inonotus baumii, and analyze its bioinformates. Methods: Taking total RNA as template, the full length cDNA and DNA of SE in I. baumii was cloned through RT-PCR and the rapid amplification of cDNA ends (RACE) technique. The bioinformatics of SE gene were analyzed by ExPASy on line. Results: Sequence analysis showed that it consisted of 2145 bp with an open reading frame (ORF) of 1 452 bp, encoding 483 amino acid polypeptides. SE gene contained six exons and five introns. The relative molecular mass of SE calculated was 5.3 × 104, the isoelectric point (pI) was 8.41, and there was no signal peptide in SE. Conclusion: It is the first report that the cDNA encoding SE from I. baumii is cloned. This work provides a scientific basis for exploring the triterpenoid biosynthesis pathway of the medicinal ingredient and improving its quality in I. baumii.