Expression and Anthocyanin Biosynthesis-Modulating Potential of Sweet Cherry (Prunus avium L.) MYB10 and bHLH Genes

Abstract

Anthocyanins are essential contributors to fruit coloration, an important quality feature and a breed determining trait of a sweet cherry fruit. It is well established that the biosynthesis of anthocyanins is regulated by an interplay of specific transcription factors belonging to MYB and bHLH families accompanied by a WD40 protein. In this study, we isolated and analyzed PaWD40, PabHLH3, PabHLH33, and several closely related MYB10 gene variants from different cultivars of sweet cherry, analyzed their expression in fruits with different anthocyanin levels at several developmental stages, and determined their capabilities to modulate anthocyanin synthesis in leaves of two Nicotiana species. Our results indicate that transcription level of variant PaMYB10.1-1 correlates with fruit coloration, but anthocyanin synthesis in Nicotiana was induced by another variant, PaMYB10.1-3, which is moderately expressed in fruits. The analysis of two fruit-expressed bHLH genes revealed that PabHLH3 enhances MYB-induced anthocyanin synthesis, whereas PabHLH33 has strong inhibitory properties.

Coordinated Regulation of Anthocyanin Biosynthesis Genes Confers Varied Phenotypic and Spatial-Temporal Anthocyanin Accumulation in Radish (Raphanus sativus L.)

“…It is speculated that this occurrence is associated with the coordination of plant metabolism because of the ability of plants to regulate the metabolism in respective organs at various developmental stages (Majdi et al, 2014). These results concur with those found in yam, cherry, grape, and chili (Aza-Gonzalez et al, 2013; Liu et al, 2013; Xie et al, 2015; Yin et al, 2015). There was also a difference in the accumulation of anthocyanin in tissues of different radish at each developmental stage.…”

“…These include cherry (Liu et al, 2013), dendrobium (Kriangphan et al, 2015), mulberry (Li et al, 2014), grape (Xie et al, 2015) and yam (Yin et al, 2015). It was suggested that patterns of anthocyanin biosynthesis in different grape berry tissues are discontinuous, implying that ABGs are regulated spatially and temporally (Falginella et al, 2012; Xie et al, 2015).…”

TheR2R3MYBtranscription factorPavMYB10.1involves in anthocyanin biosynthesis and determines fruit skin colour in sweet cherry (Prunus aviumL.)

“…Starkevič isolated and analysed several closely related MYB10 genes from different cultivars of sweet cherry. Their results indicated that transcription level of variant PaMYB10.1 correlates with fruit coloration (Starkevič et al ., ). In this study, PavMYB10.1 and PavMYB10.2 were mapped to the same region on LG 3 (Figure ).…”

“…Several MYB10 genes were isolated and analysed from different cultivars of sweet cherry. By homology to the related peach genes, the shorter gene was named PaMYB10.1 , and the longer was named PaMYB10.2 (Starkevič et al ., ). The role of the homologues and orthologues of these genes as regulators of anthocyanin biosynthesis has been shown previously in Prunus species.…”

Cloning and bioinformatic analysis of transcription factor MYB10 from the red-leaf peach

“…In certain plants, MYB proteins regulate anthocyanin biosynthesis by interacting with bHLH proteins, a mechanism that has been widely studied in petunias (Quattrocchio et al, 2006;Boase et al, 2015), snapdragons (Schwinn et al, 2006;Butelli et al, 2008), and maize (Grotewold et al, 1998;Dong et al, 2015). In Arabidopsis thaliana, TT2, TT8, and TTG1 encode an R2R3-MYB domain protein, a bHLH transcription factor, and a WD40-repeat-containing protein, respectively, and their tripartite interaction regulates expression of flavonoid structural genes (Nesi et al, 2001;Starkevič et al, 2015). In this study, expression of the MYB10 gene was high, and correlated with elevated anthocyanin content in red-leaf peach (Figures 11 and 12).…”