Cloning and Bioinformatics of Chalcone Synthase Gene of Moringa oleifera

  Objective   The open reading frame and gDNA of the gene associated with the chalcone synthase (CHS), the first key enzyme in the flavonoid biosynthetic pathway in Moringa oleifera, were cloned for a bioinformatic analysis.

  Method  Primers were designed according to the M. oleifera genome in NCBI database. The leaf cDNA and genomic DNA were used as templates to amplify the MoCHS1 with PCR for a subsequent bioinformatic analysis. DNAMAN 9.0 and MEGA 10.0 were used for the multiple sequence alignment and phylogenetic tree construction.

  Result   The ORF of MoCHS1 was 1 185 bp encoded 394 amino acids. The genomic DNA spanned 1 387 bp containing 2 exons and 1 intron. MoCHS1 was a stable hydrophilic protein with a structure of 45.43% α helix and 31.98% random coil. The gene possessed conserved sequence as well as enzymatic site residues of the CHS gene superfamily, which included 7 amino acid residues of the cyclization pocket, the Cys-His-Asn catalytic triad sites, and the family signatures of CHSs (‘RLMMYQQGCFAGGTVLR’ and ‘GVLFGFGPGL’) sharing a high similarity with the CHS proteins of other species. The phylogenetic tree of MoCHS1 closely related to and in the same clade with the CHS of Carica papaya.

  Conclusion  MoCHS1 was successfully isolated from M. oleifera sharing a typical conserved structure of the CHS gene family. The results provided crucial information for further study on the genes related to the flavonoid metabolic pathway as well as the expression regulation and evolution of the CHS gene family in M. oleifera.