Identification of flavonol synthase gene from M. pinnata and its functional elucidation using cowpea genome

Abstract

Abstract Background Flavonoids are a class of key polyphenolic secondary metabolites having various roles in plants, like in growth and development, stress defense, and reproduction. Dihydroflavonols are converted into flavonols by flavonol synthase (FLS) and this enzyme belongs to the 2-oxoglutarate-dependent dioxygenases (ODD) superfamily. Millettia pinnata is important medicinal plant possessing various phytoconstituents involved in the treatment of various diseases. The FLS is involved in the synthesis of a natural flavonol 3,4′,5,7-tetrahydroxyflavone i.e., kaempferol. However, detailed information about FLS gene sequence and its characterization in M. pinnata is not available. Methods In the current investigation the full-length cDNA sequences of the FLS gene (MpFLS) was deduced by isolating RNA from M. pinnata leaf, cDNA prearaion, PCR based amplification, sequencing followed by sequence analysis. Results The full-length cDNA of MpFLS containing 952-bp open reading frame and encoding 310-amino-acid protein has been elucidated, and submitted to NCBI with accession number OM469017. Bioinformatics analysis of MpFLS protein showed 85% similarities with VuFLS (Vigna unguilata). Also, BLAST analysis of M. pinnata sequence exhibited maximum similarity with V. unguilata. Therefore, to find the possible functional characteristics of MpFLS, the genome wide investigation of this gene was performed in cowpea (V. unguilata) genome using Phytozome v13 database. Total 17 full length non-redundant VuFLSgenes were identified in V. unguilata. These genes and the corresponding proteins were examined for their physicochemical characteristics, chromosomal location, domain and motif architecture, and phylogeny. Phylogenetic and motif analysis revealed that all the proteins had the 2OG-FeII Oxy domain. The functional annotation analysis revealed their involvement in various biological processes and molecular processes. The majority of the genes at the subcellular level are found in the cytoplasm, followed by the nucleus. Conclusions Our research study provides information about FLS gene sequence in M. pinnata and its detailed characterization. Our result also revealed that MpFLSshows similarity in functional characteristics with VuFLS.