cDNA Cloning, Bioinformatics, and Expression Analysis of ApsANS in Acer pseudosieboldianum

Anthocyanin synthetase (ANS), a key enzyme in the final step of the anthocyanin synthesis pathway, catalyzes the conversion of leucoanthocyanidins to anthocyanins. In this study, an ANS structural protein (TRINITY_DN18024_c0_g1) was found to be associated with anthocyanin accumulation in Acer pseudosieboldianum leaves, named ApsANS. Real-time quantitative fluorescence PCR analysis revealed that the expression of ApsANS was significantly higher in red-leaved (variant) than green-leaved (wild-type) strains, which was consistent with the transcriptome data. The UPLC results showed that the cyanidin metabolites may be the key substance influencing the final color formation of Acer pseudosieboldianum. The ApsANS gene was cloned and analyzed through bioinformatics analysis. ApsANS has a total length of 1371 bp, and it encodes 360 amino acids. Analysis of the structural domain of the ApsANS protein revealed that ApsANS contains a PcbC functional domain. Protein secondary structure predictions indicate that α-helix, irregularly coiled, and extended chains are the major building blocks. Subcellular localization predicted that ApsANS might be localized in the nucleus. The phylogenetic tree revealed that ApsANS is relatively closely related to ApANS in Acer palmatum. The prediction of miRNA showed that the ApsANS gene is regulated by miR6200. This study provides a theoretical reference for further analyzing the regulatory mechanism of leaf color formation in Acer pseudosieboldianum.