Molecular Cloning and Characterization of Two Genes Encoding Anthocyanin Synthase from Populus tomentosa

Abstract: Anthocyanidin synthase (ANS) is one of crucial enzymes in anthocyanin biosynthesis pathway in plants， which catalyzes proanthocyanidins to be converted into anthocyanins. In order to identify the function of anthocyanin synthase gene in poplar and improve leaf color of poplar by genetic engineering approach， based on the analysis of previous poplar transcriptome data， two pairs of PCR primers were designed， PCR was performed to amplify two members of ANS gene family by using genomic DNA of Populus tomentosa as template， named as PtANS1， PtANS2. The sequencing results showed that the full-length of PtANS1 and PtANS2 were 1 694 bp and 1 820 bp， respectively， which encoding 360 amino acids， and share two 88.3% identity and 91.9% similarity for two amino acid sequences. Structural analysis showed that both PtANS1 and PtANS2 contained 2 exons and 1 intron， shared highly similar for gene structures， but located on chromosome 1 and 3， respectively. The two amino acid sequences contained a conserved domain of 2OG-FeII_Oxy. Homology analysis and phylogenetic analysis indicated that PtANS1 and PtANS2 were close to cacao， litchi， grape and Arabidopsis. The transcriptome data by mining revealed that the expression trends of PtANS1 and PtANS2 in different tissues is pretty similar， but the FPKM value presented big differences between PtANS1 and PtANS2， the ratio range of FPKM value of PtANS2 to one of PtANS1 is 5-506， it suggested that PtANS2 played a more important role in the pigment synthesis and its physiological function. The important founding will lay a good foundation for further study its function.

CSTR: 32200.14.cjcb.2018.03.0007