Redox-dependent regulatory networks are affected by altered cellular or extracellular levels of reactive oxygen species (ROS). Perturbations of ROS production and scavenging homeostasis have a considerable impact on the nuclear transcriptome. While the regulatory mechanisms by which ROS modulate gene transcription in prokaryotes, lower eukaryotes, and mammalian cells are well established, new insights into the mechanism underlying redox control of gene expression in plants have only recently been known. In this review, we aim to provide an overview of the current knowledge on how ROS and thiol-dependent transcriptional regulatory networks are controlled. We assess the impact of redox perturbations and oxidative stress on transcriptome adjustments using cat2 mutants as a model system and discuss how redox homeostasis can modify the various parts of the transcriptional machinery.

Lipids are intimately associated with skin condition. This review aims to discuss the function of linoleic acid (LA, 18:2, ω-6), an essential fatty acid, in skin health and hair growth. In skin, LA can be metabolized into ω-6 unsaturated fatty acid, oxidized derivatives and incorporated into complex lipid molecules, including ω-hydroxy-ceramides. Previous research has revealed that skin diseases including acne, atopic dermatitis and psoriasis are associated with disordered LA metabolism. Studies based on animal or skin cell models suggest that LA or LA-rich vegetable oils, topically applied, exhibit diverse biological activities, including the repair of the skin barrier, the promotion of wound healing, skin whitening, photoprotection, anti-inflammatory effects and the stimulation of hair growth. Moreover, the underlying mechanisms of LA’s beneficial effects on skin are summarized. Further research on the correlation of LA metabolism and skin disorders, a deeper exploration of the mechanisms underlying the function of LA in skin management and more investigations of its clinical application are required to enhance the understanding and utilization of LA in cosmetics and pharmaceuticals.

Signaling events triggered by hydrogen peroxide (H₂O₂) regulate plant growth and defense by orchestrating a genome-wide transcriptional reprogramming. However, the specific mechanisms that govern H₂O₂-dependent gene expression are still poorly understood. Here, we identify the Arabidopsis Mediator complex subunit MED8 as a regulator of H₂O₂ responses. The introduction of the med8 mutation in a constitutive oxidative stress genetic background (catalase-deficient, cat2) was associated with enhanced activation of the salicylic acid pathway and accelerated cell death. Interestingly, med8 seedlings were more tolerant to oxidative stress generated by the herbicide methyl viologen (MV) and exhibited transcriptional hyperactivation of defense signaling, in particular salicylic acid- and jasmonic acid-related pathways. The med8-triggered tolerance to MV was manipulated by the introduction of secondary mutations in salicylic acid and jasmonic acid pathways. In addition, analysis of the Mediator interactome revealed interactions with components involved in mRNA processing and microRNA biogenesis, hence expanding the role of Mediator beyond transcription. Notably, MED8 interacted with the transcriptional regulator NEGATIVE ON TATA-LESS, NOT2, to control the expression of H₂O₂-inducible genes and stress responses. Our work establishes MED8 as a component regulating oxidative stress responses and demonstrates that it acts as a negative regulator of H₂O₂-driven activation of defense gene expression.

As a promising environmental protection technology, the application of ultraviolet B irradiation in vegetable production has been widely considered. However, the effect of UVB irradiation varies with different plant varieties. In this study, we investigated the effects of two UVB intensities (0.7, 1.4 W m⁻²) on the accumulation of phenolics and flavonoids, and antioxidant activity of green-leaf and red-leaf lettuce (Lactuca sativa L.) 7 days prior to harvest. The results indicated that short-term (within 2 days) UVB treatment could promote the increase in total chlorophyll content of red-leaf lettuce and green-leaf lettuce, which increased by 49.8% and 20.6% compared with day zero, respectively, and was beneficial to the synthesis of carotenoids of red-leaf lettuce. Extending UVB exposure time significantly decreased chlorophyll a/b value of green-leaf lettuce from 0.92 to 0.63, and simultaneously increased the accumulation of antioxidant substances such as flavonoids, which were increased by 90.0% and 183.4% compared with day zero for UVB-0.7 and UVB-1.4 treatments of red-leaf lettuce, 84.1% and 110.9% of green-leaf lettuce. In contrast, red-leaf lettuce had a higher accumulation level of secondary metabolites, faster scavenging rate of free radicals, and stronger ability to resist UVB stress. Our results suggest that supplementation of low-dose UVB radiance prior to harvest can improve the secondary metabolite content and antioxidant activity of the two kinds of lettuce. This research provided a theoretical basis for improving lettuce quality by pre-harvest UVB treatment in controlled environmental agriculture.