Analysis of Key Genes Involved in Potato Anthocyanin Biosynthesis Based on Genomics and Transcriptomics Data

Abstract

The accumulation of secondary metabolites, such as anthocyanins, in cells plays an important role in colored plants. The synthesis and accumulation of anthocyanins are regulated by multiple genes, of which the R2R3-MYB transcription factor gene family plays an important role. Based on the genomic data in the Potato Genome Sequencing Consortium database (PGSC) and the transcriptome data in the SRA, this study used potato as a model plant to comprehensively analyze the plant anthocyanin accumulation process. The results indicated that the most critical step in the synthesis of potato anthocyanins was the formation of p -coumaroyl-CoA to enter the flavonoid biosynthetic pathway. The up-regulated expression of the CHS gene and the down-regulated expression of HCT significantly promoted this process. At the same time, the anthocyanins in the potato were gradually synthesized during the process from leaf transport to tubers. New transcripts of stAN1 and PAL were cloned and named stAN1-like and PAL-like , respectively, but the functions of these two new transcripts still need further study. In addition, the sequence characteristics of amino acids in the R2-MYB and R3-MYB domains of potato were preliminarily identified. The aims of this study are to identify the crucial major genes that affect anthocyanin biosynthesis through multi-omics joint analysis and to transform quantitative traits into quality traits, which provides a basis and reference for the regulation of plant anthocyanin biosynthesis. Simultaneously, this study provides the basis for improving the anthocyanin content in potato tubers and the cultivation of new potato varieties with high anthocyanin content.

Identification of a novel anthocyanin synthesis pathway in the fungus Aspergillus sydowii H-1

“…C4H and CHS are vital functional genes in existing studies regarding the process of anthocyanin genes [6,8,75]. However, CHS and C4H could be assembled only by the de novo method, which suggests that the reference genome, CBS 593.65 [35], may not contain these two genes.…”

“…Among the genes involved in anthocyanin synthesis, C4H is one of the core genes of the phenylpropanoid pathway and mediates the synthesis of secondary metabolites such as anthocyanins [6] and artemisinin [7]. CHS links the phenylpropanoid pathway and the flavonoid pathway as well as plays an important role in the biosynthesis of anthocyanins [8].…”

Pathway-based analysis of anthocyanin diversity in diploid potato

“…The anthocyanin biosynthetic pathway is one of the most extensively studied pathways of plant specialized metabolism. Several genes have been reported to determine anthocyanin levels in potato cultivars and accessions [20,21]. However, we know little about the causes of anthocyanin variation in potato landraces, which have a broader and largely untapped genetic diversity [5].…”

“…Naringenin is hydrolyzed to dihydroflavonols by three enzymes, namely flavanone-3-hydroxylase (F3H), flavonoid-3´-hydroxylase (F3´H) and flavonoid-3´,5´-hydroxylase (F3'5'H). The dihydroflavonols are reduced to three different leucoanthocyanidins by dihydroflavonol-4-reductase (DFR), and their glycosylation by leucoanthocyanidin dioxygenase/anthocyanidin synthase (LDOX/ANS) produces the basic structures of anthocyanins (anthocyanidins-aglycons) that determine the coloration in plant tissues [18][19][20][21]. Genes encoding anthocyanin biosynthetic enzymes are known as "structural genes'' and they are conserved among different species [22].…”

“…This gene governs the expression of multiple enzymes in the pathway, therefore affecting the level of multiple anthocyanin pigments [33]. Recently, a number of regulatory genes potentially controlling anthocyanin biosynthetic structural genes have been identified in potato tubers [20,22,34,35] including three R2R3-MYB encoding genes (StAN1, StMYBA1 and StMYB113) [20,21,36] two bHLH genes (StJAF13 and StbHLH1) [21,37] and one WD40 (StWD40) [38].…”