Sequence and epigenetic variations of R2R3-MYB transcription factors determine the diversity of taproot skin and flesh colors in different cultivated types of radish (Raphanus sativus L.).

KEY MESSAGE: This study found that three paralogous R2R3-MYB transcription factors exhibit functional divergence among different subspecies and cultivated types in radish. Cultivated radish taproots exhibit a wide range of color variations due to unique anthocyanin accumulation patterns in various tissues. This study investigated the universal principles of taproot color regulation that developed during domestication of different subspecies and cultivated types. The key candidate genes RsMYB1 and RsMYB2, which control anthocyanin accumulation in radish taproots, were identified using bulked segregant analysis in two genetic populations. We introduced the RsMYB1-RsF3'H-RsMYB1Met genetic model to elucidate the complex and unstable genetic regulation of taproot flesh color in Xinlimei radish. Furthermore, we analyzed the expression patterns of three R2R3-MYB transcription factors in lines with different taproot colors and investigated the relationship between RsMYB haplotypes and anthocyanin accumulation in a natural population of 56 germplasms. The results revealed that three paralogous RsMYBs underwent functional divergence during radish domestication, with RsMYB1 regulating the red flesh of Xinlimei radish, and RsMYB2 and RsMYB3 regulating the red skin of East Asian big long radish (R. sativus var. hortensis) and European small radish (R. sativus var. sativus), respectively. Moreover, RsMYB1-H1, RsMYB2-H10, and RsMYB3-H6 were identified as the primary haplotypes exerting regulatory functions on anthocyanin synthesis. These findings provide an understanding of the genetic mechanisms regulating anthocyanin synthesis in radish and offer a potential strategy for early prediction of color variations in breeding programs.

Slow-sculpting graphene oxide/alginate gel loaded with platelet-rich plasma to promote wound healing in rats.

Wounds, especially chronic wounds, have become an important problem that endangers human health. At present, there are many repair methods, and among them combines materials science and biology is one of the important repair methods. This study explored the preparation method, physicochemical properties, biological activity and safety of Platelet-Rich plasma (PRP)-loaded slow-sculpting graphene oxide (GO)/alginate gel, and applied it to acute full-thickness skin defect wounds in rats to observe its role in wound healing. The results show that the slow-sculpting GO/alginate gel has excellent plasticity and is suitable for a variety of irregularly shaped wounds. At the same time, its porous structure and water content can maintain the activity of platelets and their released growth factors in PRP, thereby promoting wound collagen synthesis and angiogenesis to accelerate wound healing. This indicates that the slow-sculpting GO/alginate gel is an excellent loading material for PRP, and the combination of the two may become one of the methods to promote wound repair.

A Comparative Study on Platelet-Rich Plasma From Elderly Individuals and Young Adults to Treat Pressure Ulcers in Mice.

OBJECTIVE: The aim of the present study was to compare the therapeutic effects of activated platelet-rich plasma (PRP) prepared from elderly individuals and young adults to treat pressure ulcers (PUs), and to accumulate a theoretical basis for allogeneic PRP treatment of PUs in elderly patients. MATERIALS AND METHODS: Whole blood was extracted from elderly individuals aged >65 y and young adult volunteers for PRP preparation, and platelet concentrations in whole blood and PRP were compared. Growth factors released from activated PRP were assayed using the enzyme-linked immunosorbent assay. C57BL/6 mice were divided into three groups: the control saline, elderly-PRP (Group A), and young adult-PRP (Group B). Ischemia-reperfusion injury-induced PUs were established on the backs of mice. PUs were photographed on days 0, 5, and 10 to assess their sizes. Specimens were collected on day 10 and subjected to hematoxylin and eosin and Masson's staining. Immunohistochemical staining for CD31 was conducted to evaluate vascular formation, and cell invasion was assessed using a Transwell assay. The action of PRP on transforming growth factor-beta (TGF-ß)-dependent fibroblast activity and epithelial-mesenchymal transition was analyzed using immunofluorescence and Western blotting in vitro. RESULTS: The platelet concentrations in whole blood and PRP of young adults were significantly higher than that in elderly individuals. The two PRP treatment groups had similar platelet enrichment coefficients of PRP. After activation, PRP from young adults produced significantly higher levels of platelet-derived growth factor, TGF-ß, and vascular endothelial growth factor than PRP from elderly individuals (P < 0.05). The concentrations of platelet-derived growth factor, TGF-ß, and vascular endothelial growth factor were positively correlated with the platelet concentrations in whole blood and PRP. The effects of PRP in regulating the expressions of TGF-ß, α-smooth muscle actin, vimentin, and E-cadherin were observed in vivo and in vitro. The two PRP treatment groups exhibited better wound healing than the control group, as evidenced by more re-epithelialization, higher collagen content, skin fibrosis, and more blood vessel formation over time. Group B exhibited better wound healing than Group A (P < 0.05). CONCLUSION: PRP exhibits potent wound healing ability in PU therapy, and PRP from young adults is seemingly superior to that from elderly individuals because of a higher concentration of platelets and increased production of growth factors.