Gene cloning and sequence analysis of caffeic acid O-methyltransferase in Angelica sinensis / 中草药

ABSTRACT

Objective: To clone the full-length cDNA of caffeic acid O-methyltransferase (COMT) encoding gene from Angelica sinensis and to perform bioinformatic analysis for the cDNA sequence. Methods: Extracting the total RNA from the leaves of A. sinensis as cDNA synthesis template, the full length COMT cDNA of A. sinensis was cloned through homology-based cloning and rapid amplification of cDNA ends (RACE) technique. The bioinformatics of the cDNA sequence was analyzed by Blast N, Blast P, ORF Finder, Compute PI/Mw, ProtScale, PROSITE, and SWISS-MODEL sequences online analysis tools on NCBI, ExPASy, DNAMAN, and MEGA softwares. Results: The full-length of COMT cDNA (1 436 bp) was obtained (GenBank accession number KP188587). It included 5'-UTR (76 bp) and 3'-UTR (362 bp), with an open reading frame (ORF) of 1 098 bp, encoding 365 amino acid polypeptides. The relative molecular mass of COMT calculated was 40 230, theoretical isoelectric point (PI) was 5.43, and there was no signal peptide in COMT. The protein sequence contained typical class II O-methyltransferases domain SAM_OMT_II. Conclusion: A novol cDNA encoding COMT from A. sinensis is cloned. This work might establish an experimental basis for exploring COMT gene function and the biosynthetic and regulation of ferulic acid (FA) in A. sinensis.