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The yellow-fleshed loquat is abundant in carotenoids, which determine the fruit's color, provide vitamin A, and offer anti-inflammatory and anti-cancer health benefits. In this research, the impact of abscisic acid (ABA), a plant hormone, on carotenoid metabolism and flesh pigmentation in ripening loquat fruits was determined. Results revealed that ABA treatment enhanced the overall content of carotenoids in loquat fruit, including major components like β-cryptoxanthin, lutein, and β-carotene, linked to the upregulation of most genes in the carotenoid biosynthesis pathway. Furthermore, a transcription factor, EjWRKY6, whose expression was induced by ABA, was identified and was thought to play a role in ABA-induced carotenoid acceleration. Transient overexpression of EjWRKY6 in Nicotiana benthamiana and stable genetic transformation in Nicotiana tabacum with EjWRKY6 indicated that both carotenoid production and genes related to carotenoid biosynthesis could be upregulated in transgenic plants. A dual-luciferase assay proposed a probable transcriptional control between EjWRKY6 and promoters of genes associated with carotenoid production. To sum up, pre-harvest ABA application could lead to carotenoid biosynthesis in loquat fruit through the EjWRKY6-induced carotenoid biosynthesis pathway. [ABSTRACT FROM AUTHOR]

BACKGROUND: Melatonin, a hormone present in animals and some plants, has garnered attention for its potential in preserving harvested produce. Softening due to changes in cell wall composition and wilting caused by weight loss are the major reasons for the loss of commercial value in postharvest okra. This study aimed to evaluate the impact of melatonin on the softening and weight loss of postharvest okra. RESULTS: The results revealed that the application of melatonin had a significant influence on the maintenance of fruit firmness by inhibiting the breakdown and dissolution of cell wall polysaccharides by suppressing the expression of specific genes responsible for cell wall degradation in okra. Conversely, melatonin treatment positively influenced the expression of genes involved in the synthesis of cell wall components. Furthermore, the treatment exhibited notable benefits in reducing weight loss in okra, which was accomplished by promoting the closure of stomata – the tiny pores on the surface of the fruit. CONCLUSION: Melatonin could serve as a novel approach to reduce water loss, delay fruit softening and extend the shelf life of okra. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Lung cancer is a leading cause of cancer‐related deaths worldwide. Recent studies have identified pyroptosis, a type of programmed cell death, as a critical process in the development and progression of lung cancer. In this study, we investigated the effect of EEBR, a new compound synthesized by our team, on pyroptosis in non‐small cell lung cancer cells (NSCLC) and the underlying molecular mechanisms. Our results demonstrated that EEBR significantly reduced the proliferation and metastasis of NSCLC cells in vitro. Moreover, EEBR‐induced pyroptosis in NSCLC cells, as evidenced by cell membrane rupture, the release of cytokines such as interleukin‐18 and interleukin‐1 beta and the promotion of Gasdermin D cleavage in a Caspase‐1‐dependent manner. Furthermore, EEBR promoted the nuclear translocation of NF‐κB and upregulated the protein level of NLRP3. Subsequent studies revealed that EEBR‐induced pyroptosis was suppressed by the inhibition of NF‐κB. Finally, EEBR effectively suppressed the growth of lung cancer xenograft tumours by promoting NSCLC pyroptosis in animal models. Taken together, our findings suggest that EEBR induces Caspase‐1‐dependent pyroptosis through the NF‐κB/NLRP3 signalling cascade in NSCLC, highlighting its potential as a candidate drug for NSCLC treatment. [ABSTRACT FROM AUTHOR]

Simple Summary: Color is one of the most significant quality characteristics of Chinese bayberry (Morella rubra). Exploration of the anthocyanin biosynthesis mechanism is crucial for the genetic improvement of color quality. Many MYB transcription factors are reported to control the biosynthesis of anthocyanins in a variety of plant species. However, it is still unclear how the MYB genes in Chinese bayberry contribute to the synthesis of anthocyanins. In this research, we isolated the MYB transcription factor, MrMYB9, based on comparative transcriptome analysis of red and white Chinese bayberry fruits. We also profiled MrMYB9 gene expression during the maturation period and in specific tissues. Through bioinformatics and molecular biology experiments, MrMYB9 was subsequently identified as a transcription factor of the R2R3-MYB type associated with anthocyanin biosynthesis. Our research sheds insights on the biosynthesis of anthocyanins during color maturation in the Chinese bayberry. Anthocyanin is a class of water-soluble flavonoids found in Chinese bayberry (Morella rubra) that is not only responsible for the variety of colors visible in nature but also has numerous health-promoting benefits in humans. Through comparative transcriptomics, we isolated and identified a transcription factor (TF) of the R2R3-MYB type, MrMYB9, in order to explore the anthocyanin biosynthesis pathway in red and white Chinese bayberries. MrMYB9 transcript was positively correlated with anthocyanin level and anthocyanin biosynthetic gene expression during Chinese bayberry fruit maturation (R-values in the range 0.54–0.84, p < 0.05). Sequence analysis revealed that MrMYB9 shared a similar R2R3 domain with MYB activators of anthocyanin biosynthesis in other plants. MrMYB9 substantially transactivated promoters of anthocyanin biosynthesis-related EBGs (MrCHI, MrF3'H, and MrANS) and LBGs (MrUFGT) upon co-expression of the AtEGL3 gene. Our findings indicated that MrMYB9 may positively modulate anthocyanin accumulation in Chinese bayberry. [ABSTRACT FROM AUTHOR]

The priming of defence responses in pathogen‐challenged model plants undergoes a preparation phase and an expression phase for defence function. However, the priming response in postharvest fruits has not been elucidated. Here, we found that 50 mM β‐aminobutyric acid (BABA) treatment could induce two distinct pathways linked with TGA1‐related systemic acquired resistance (SAR), resulting in the alleviation of Rhizopus rot in postharvest peach fruit. The first priming phase was elicited by BABA alone, leading to the enhanced transcription of redox‐regulated genes and posttranslational modification of PpTGA1. The second phase was activated by an H2O2 burst via up‐regulation of PpRBOH genes and stimulation of the MAPK cascade on pathogen invasion, resulting in a robust defence. In the MAPK cascade, PpMAPKK5 was identified as a shortcut interacting protein of PpTGA1 and increased the DNA binding activity of PpTGA1 for the activation of salicylic acid (SA)‐responsive PR genes. The overexpression of PpMAPKK5 in Arabidopsis caused the constitutive transcription of SA‐dependent PR genes and as a result conferred resistance against the fungus Rhizopus stolonifer. Hence, we suggest that the BABA‐induced priming defence in peaches is activated by redox homeostasis with an elicitor‐induced reductive signalling and a pathogen‐stimulated H2O2 burst, which is accompanied by the possible phosphorylation of PpTGA1 by PpMAPKK5 for signal amplification. [ABSTRACT FROM AUTHOR]