Search Results (4)

The ATP-binding cassette (ABC) transporter family is a large and diverse protein superfamily that plays various roles in plant growth and development. Although the ABC transporters are known to aid in the transport of a wide range of substrates across biological membranes, their role in anthocyanin transport remains elusive. In this study, we identified a total of 132 putative ABC genes in the peach genome, and they were phylogenetically classified into eight subfamilies. Variations in spatial and temporal gene expression levels resulted in differential expression patterns of PpABC family members in various tissues of peach. PpABCC1 was identified as the most likely candidate gene essential for anthocyanin accumulation in peach. Transient overexpression of PpABCC1 caused a significant increase in anthocyanin accumulation in tobacco leaves and peach fruit, whereas virus-induced gene silencing of PpABCC1 in the blood-fleshed peach resulted in a significant decrease in anthocyanin accumulation. The PpABCC1 promoter contained an MYB binding cis-element, and it could be activated by anthocyanin-activator PpMYB10.1 based on yeast one-hybrid and dual luciferase assays. Thus, it seems that PpABCC1 plays a crucial role in anthocyanin accumulation in peach. Our results provide a new insight into the vacuolar transport of anthocyanins in peach. Full article

Fruit color is an important trait in peach from the point of view of consumer preference, nutritional content, and diversification of fruit typologies. Several genes and phenotypes have been described for peach flesh and skin color, and although peach color knowledge has increased in the last few years, some fruit color patterns observed in peach breeding programs have not been carefully described. In this work, we first describe some peach mesocarp color patterns that have not yet been described in a collection of commercial peach cultivars, and we also study the genetic inheritance of the red dots present in the flesh (RDF) and red color around the stone (CAS) in several intra- and interspecific segregating populations for both traits. For RDF, we identified a QTL at the beginning of G5 in two intraspecific populations, and for CAS we identified a major QTL in G4 in both an intraspecific and an interspecific population between almond and peach. Finally, we discuss the interaction between these QTLs and some other genes previously identified in peach, such as dominant blood flesh (DBF), color around the stone (Cs), subacid (D) and the maturity date (MD), and the implications for peach breeding. The results obtained here will help peach germplasm curators and breeders to better characterize their plant materials and to develop an integrated system of molecular markers to select these traits. Full article

The purpose of this study was to explore the drying kinetics, effective moisture diffusivity, activation energy, color variation, and the thermal degradation properties of anthocyanins of blood-flesh peach under hot air drying for the first time. The results showed that the hot air-drying process of blood-flesh peach belongs to reduced-speed drying. The Page model could accurately predict the change of moisture ratio of blood-flesh peach. The effective moisture diffusivity during hot air drying of blood-flesh peach was in the range between 1.62 × 10⁻¹⁰ and 2.84 × 10⁻¹⁰ m²/s, and the activation energy was 25.90 kJ/mol. Fresh samples had the highest content (44.61 ± 4.76 mg/100 g) of total monomeric anthocyanins, and it decreased with the increase of drying temperature. Cyanidin-3-O-glucoside and delphinidin-3-O-galactoside were the main anthocyanins of blood-flesh peach as identified and quantified by UPLC-QqQ-MS. Interestingly, during the drying process, the content of cyanidin-3-O-glucoside increased at the beginning, and then decreased. However, the content of delphinidin-3-O-galactoside kept decreasing during the whole drying process. Considering the drying efficiency, fruit color and quality, 70 °C would be a suitable temperature for drying blood-flesh peach. This research will provide beneficial information for understanding the anthocyanin degradation of blood-flesh peach during drying, and guide the production of high-quality dried products. Full article

Anthocyanins are a class of water-soluble flavonoids widely present in fruits and vegetables responsible for the red flesh formation of peach fruit. Previously, several genes of the MYB family have been reported as transcriptional regulators of the anthocyanin biosynthetic pathway of structural genes in plants. In this study, through comparative transcriptome analysis of the white and red flesh peach cultivars of Harrow Blood and Asama Hakuto, a predicted transcription factor of the R2R3MYB family, PpMYB39, was identified to be associated with anthocyanin biosynthesis in peach fruit. In red-fleshed peach cultivars, the maximum amount of anthocyanin accumulated 95 days after full bloom (DAFB), at full maturity near ripening. Our results showed that, at this stage, PpMYB39 had the highest expression level among the 13 differentially expressed genes (DEGs) found in both red- and white-fleshed fruits, as well as a high correlation with total anthocyanin content throughout fruit development. Moreover, the expression analysis of the structural genes of the anthocyanin biosynthetic pathway in peach fruit revealed that Prunus persica Dihydroflavonol-4-reductase (PpDFR) was co-expressed and up-regulated with PpMYB39 at 95 DAFB, suggesting its possible role as a transcriptional activator of MYB39. This was further confirmed by a yeast one-hybrid assay and a dual luciferase reporter assay. Our results will be helpful in the breeding of peach cultivars and the identification and significance of color in peaches and related fruit species, in addition to providing an understanding of color formation in peach fruit for future research. Full article