Anthocyanins Profiling Analysis and RNA-Seq Revealed the Dominating Pigments and Coloring Mechanism in Cyclamen Flowers

Abstract

Pigments in cyclamen (Cyclamen purpurascens) endows flowers with great ornamental and medicinal values. However, little is known about the biosynthetic pathways of pigments, especially anthocyanins, in cyclamen flowers. Herein, anthocyanins profiling and RNA-Seq were used to decipher the molecular events using cyclamen genotypes of red (HXK) or white (BXK) flowers. We found that red cyclamen petals are rich in cyanidin-3-O-rutinoside, cyanidin-3-O-glucoside, delphinidin-3-O-glucoside, malvidin-3-O-glucoside, peonidin-3-O-rutinoside, quercetin-3-O-glucoside, and ruti. In addition, our transcriptomics data revealed 3589 up-regulated genes and 2788 down-regulated genes comparing the BXK to HXK. Our rich dataset also identified eight putative key genes for anthocyanin synthesis, including four chalcone synthase (CHS, g13809_i0, g12097_i0, g18851_i0, g36714_i0), one chalcone isomerase (CHI, g26337_i0), two flavonoid 3-hydroxylase (F3′H, g14710_i0 and g15005_i0), and one anthocyanidin synthase (ANS, g18981_i0). Importantly, we found a 2.5 order of magnitude higher expression of anthocyanin 3-O-glucosyltransferase (g8206_i0), which encodes a key gene in glycosylation of anthocyanins, in HXK compared to BXK. Taken together, our multiomics approach demonstrated massive changes in gene regulatory networks and anthocyanin metabolism in controlling cyclamen flower color.

Metabolome analysis reveals flavonoid changes during the leaf color transition in Populus × euramericana ‘Zhonghuahongye’

“…Anthocyanins are an important class of water-soluble pigments, with 6 common types: pelargonidin (Pg), cyanidin (Cy), delphinidin (Dp), peonidin (Pn), petunidin (Pt), and malvidin (Mv) ( Chen et al., 2023 ). Pelargonidin is associated with a brick-red color, cyanidin and peonidin lead to a purplish-red color, and delphinidin, petunidin, and malvidin cause a blue−purple color ( Hughes and Lev-Yadun, 2015 ; Xia et al., 2022 ). Anthocyanins contribute directly to leaf color, and other nonanthocyanin polyphenols also influence leaf coloration through auxin effects, with flavanols and flavones having the most significant effect on flower and leaf color ( Song et al., 2017 ).…”

Optimization of Anthocyanin Production in Tobacco Cells

“…Anthocyanins are plant-derived, water-soluble, and bioactive secondary metabolites and are liable for the coloring of different plant organs like leaves, stems, roots, flowers, fruits, and grains as red, purple, and blue colors [ 1 , 2 , 3 ]. They are the flavonoid class of polyphenols and biosynthesized through the phenylpropanoid pathway starting from the essential amino acid phenylalanine.…”

Editorial: Advances in metabolism and chemodiversity – focus – anthocyanin and proanthocyanin: biosynthesis, accumulation, regulation

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Editorial on the Research TopicAdvances in metabolism and chemodiversityfocusanthocyanin and proanthocyanin: biosynthesis, accumulation, regulation Anthocyanins and proanthocyanidins are water soluble, bioactive, secondary metabolites of the flavonoid class of plant pigments. They are responsible for red, purple, blue colours of vegetative and reproductive parts of plants (Figure 1) while proanthocyanidins are brown colour in some tissues (seed, peel and bark) or nonvisible pigments (Rahim et al, 2014;Zhao et al, 2010;Xia et al, 2022). They improve the fruit and vegetable quality and are beneficial to human health.

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