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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]

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]

Summary The effects of ultrasound (US) pretreatment combined with drying process on storage quality maintenance and bioactive compound accumulation of broccoli stems were investigated. Results indicated that US pretreatment (λ = 8.5 mm) delayed the decline of L* value and ascorbic acid content but inhibited the increase of a* and b* values, browning index, and microbial counts of fresh‐cut broccoli stems. Furthermore, the US application enhanced total phenolics content by activating phenylalanine ammonia‐lyase, cinnamate‐4‐hydroxylase, and 4‐coumarate‐CoA ligase in phenylpropane metabolism. Meanwhile, it also promoted γ‐aminobutyric acid (GABA) accumulation by upregulating activities of diamine oxidase, polyamine oxidase, and aminoaldehyde dehydrogenase in GABA shunt and polyamine degradation pathway, respectively, which in turn, accelerated the biosynthesis of GABA from polyamines and glutamate. In addition, compared with other three drying methods, the combined vacuum freeze drying (VFD) could further retain the sensory attributes and bioactive compounds to a maximum extent in dehydrated broccoli stems. Hence, current findings illustrated that US pretreatment combined with VFD process is beneficial for commercial quality maintenance and nutritional value enhancement, thus providing new perspectives on the comprehensive utilisation of broccoli stems. [ABSTRACT FROM AUTHOR]

GABA is able to increase resistance to biotic and abiotic stresses in fresh-cut fruits and vegetables. Therefore, the objective of this research was to explore the potential regulatory mechanisms of γ-aminobutyric acid (GABA) accumulation in fresh-cut stem lettuce following GABA treatment. The evidence showed that exogenous GABA stimulated the GABA shunt by elevating glutamate levels, the activities of GABA transaminase (GABA-T) and glutamate decarboxylase (GAD). Similarly, GABA stimulated polyamine metabolism by increasing the activities of 4-amino aldehyde dehydrogenase (AMADH), polyamine oxidase (PAO) and diamine oxidase (DAO), as well as elevating free polyamines, arginine and ornithine levels. Subsequently, GABA application up-regulated the expression of GABA shunt genes and polyamine metabolism genes. Additionally, GABA treatment resulted in the down-regulation of LsMYB44 and LsWRKY12 expressions. Notably, LsMYB44 bound to MYB binding sites in the LsGAD, LsGABAT1, LsADC1, LsPAO2, LsALDH7B4 promoters and repressed transcription of these genes. The interaction between LsMYB44 and LsWRKY12 was associated with the transcriptional repression of polyamine metabolism and GABA shunt genes by LsMYB44. In conclusion, LsMYB44 and LsWRKY12 downregulated the transcription of key genes of GABA shunt and polyamine metabolism in fresh-cut lettuce. This downregulation, however, was alleviated by the application of GABA, thereby promoting endogenous GABA accumulation., Competing Interests: Declaration of competing interest, (Copyright © 2024. Published by Elsevier B.V.)