The Regulation of Floral Colour Change in Pleroma raddianum (DC.) Gardner

Abstract

Floral colour change is a widespread phenomenon in angiosperms, but poorly understood from the genetic and chemical point of view. This article investigates this phenomenon in Pleroma raddianum, a Brazilian endemic species whose flowers change from white to purple. To this end, flavonoid compounds and their biosynthetic gene expression were profiled. By using accurate techniques (Ultra Performance Liquid Chromatography-High-Resolution Mass Spectrometry (UPLC-HRMS)), thirty phenolic compounds were quantified. Five key genes of the flavonoid biosynthetic pathway were partially cloned, sequenced, and the mRNA levels were analysed (RT-qPCR) during flower development. Primary metabolism was also investigated by gas chromatography coupled to mass spectrometry (GC-EIMS), where carbohydrates and organic acids were identified. Collectively, the obtained results suggest that the flower colour change in P. raddianum is determined by petunidin and malvidin whose accumulation coincides with the transcriptional upregulation of early and late biosynthetic genes of the flavonoid pathway, mainly CHS and ANS, respectively. An alteration in sugars, organic acids and phenolic co-pigments is observed together with the colour change. Additionally, an increment in the content of Fe3+ ions in the petals, from the pink to purple stage, seemed to influence the saturation of the colour.

Metabolome and transcriptome analyses of anthocyanin biosynthesis reveal key metabolites and candidate genes in purple wheat (Triticum aestivum L.)

“…In A. thaliana , Fragaria pentaphylla , and Malus crabapple , the expression level of CHS is tightly associated with the content of anthocyanins, and gene suppression or overexpression will decrease or increase the anthocyanin content, respectively (Lunkenbein et al, 2006; Shen et al, 2020; Tai et al, 2014; Zhang et al, 2018). Rezende et al (2020) further showed that CHS is linked to the synthesis of malvidin (Rezende et al, 2020). F3H and UFGT are key structural genes in the anthocyanin biosynthesis pathway, and their expression levels directly affect anthocyanin synthesis (Aza‐Gonzalez et al, 2013; Wei et al, 2011; Zhao et al, 2012).…”

“…In A. thaliana, Fragaria pentaphylla, and Malus crabapple, the expression level of CHS is tightly associated with the content of anthocyanins, and gene suppression or overexpression will decrease or increase the anthocyanin content, respectively (Lunkenbein et al, 2006;Shen et al, 2020;Tai et al, 2014;Zhang et al, 2018). Rezende et al (2020) further showed that CHS is linked to the synthesis of malvidin (Rezende et al, 2020).…”

Comparative Analysis of the Effects of Internal Factors on the Floral Color of Four Chrysanthemum Cultivars of Different Colors

“…The powder was used for the determination of metal ions. Na + , K + , Fe 3+ , Ca 2+ , Mg 2+ , Cu 2+ , and Zn 2+ in the powder of ray florets were measured through flame atomic absorption spectrometry according to a previously reported method [36].…”

Response of Anthocyanin Accumulation in Pepper (Capsicum annuum) Fruit to Light Days

“…Pepper fruit grows to its maximum size about 21 days after pollination and the purple color is prominent throughout the growth stage [ 21 , 22 ]. Anthocyanins are continuously synthesized throughout the development period of immature fruit of pepper, but which time point is the key period of anthocyanin synthesis and which gene plays a key role in this process still need to be elucidated [ 23 , 24 ].…”