Molecular Structure Characterization of Fagopyrum tataricum Chalcone Synthase and Its Tissue-specific Expression during Florescence

The full length DNA and cDNA sequence of chalcone synthase gene(CHS) from Fagopyrum tataricum was isolated by homology cloning,genomic-walking,and RT-PCR.The CHS gene of F.tataricum(GU172165) is 1 632 bp,including a 445 bp intron;the coding region of cDNA(HM852753) is 1 188 bp,and it encodes a protein with 395 amino acids designated as FtCHS.Sequence analysis revealed that both FtCHS′s nucleotide and deduced amino acid sequences were highly identical with those of other plants(over 95% in similarity).FtCHS possesses four CHS-specific conserved motifs: a CHS-family Tag sequence(GFGPG),an active site,a substrate-binding pocket,and a cyclization pocket.The semi-quantitative RT-PCR analysis showed that FtCHS gene was highly expressed in immature seed,followed by leaf,stem and flower in amount,while lower in root and mature seed.The expression pattern of FtCHS gene is consistent to the distribution of rutin content in those tissues of F.tataricum,which indicated FtCHS′s expression had the tissue-specific during florescence.