Neglected PTM in Animal Adipogenesis: E3-mediated Ubiquitination

Targeting epigenetic and post-translational modifications of NRF2: key regulatory factors in disease treatment

Nuclear factor erythroid 2-related factor 2 (NRF2) is a key transcription factor involved in regulating cellular antioxidant defense and detoxification mechanisms. It mitigates oxidative stress and xenobiotic-induced damage by inducing the expression of cytoprotective enzymes, including HO-1 and NQO1. NRF2 also modulates inflammatory responses by inhibiting pro-inflammatory genes and mediates cell death pathways, including apoptosis and ferroptosis. Targeting NRF2 offers potential therapeutic avenues for treating various diseases. NRF2 is regulated through two principal mechanisms: post-translational modifications (PTMs) and epigenetic alterations. PTMs, including phosphorylation, ubiquitination, and acetylation, play a pivotal role in modulating NRF2's stability, activity, and subcellular localization, thereby precisely controlling its function in the antioxidant response. For instance, ubiquitination can lead to NRF2 degradation and reduced antioxidant activity, while deubiquitination enhances its stability and function. Epigenetic modifications, such as DNA methylation, histone modifications, and interactions with non-coding RNAs (e.g., MALAT1, PVT1, MIR4435-2HG, and TUG1), are essential for regulating NRF2 expression by modulating chromatin architecture and gene accessibility. This paper systematically summarizes the molecular mechanisms by which PTMs and epigenetic alterations regulate NRF2, and elucidates its critical role in cellular defense and disease. By analyzing the impact of PTMs, such as phosphorylation, ubiquitination, and acetylation, as well as DNA methylation, histone modifications, and non-coding RNA interactions on NRF2 stability, activity, and expression, the study reveals the complex cellular protection network mediated by NRF2. Furthermore, the paper explores how these regulatory mechanisms affect NRF2's roles in oxidative stress, inflammation, and cell death, identifying novel therapeutic targets and strategies. This provides new insights into the treatment of NRF2-related diseases, such as cancer, neurodegenerative disorders, and metabolic syndrome. This research deepens our understanding of NRF2's role in cellular homeostasis and lays the foundation for the development of NRF2-targeted therapies.

Advancements in omics technologies: Molecular mechanisms of acute lung injury and acute respiratory distress syndrome (Review)

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is an inflammatory response arising from lung and systemic injury with diverse causes and associated with high rates of morbidity and mortality. To date, no fully effective pharmacological therapies have been established and the relevant underlying mechanisms warrant elucidation, which may be facilitated by multi‑omics technology. The present review summarizes the application of multi‑omics technology in identifying novel diagnostic markers and therapeutic strategies of ALI/ARDS as well as its pathogenesis.

CUL1 exacerbates glucocorticoid-induced osteoporosis by enhancing ASAP1 ubiquitination

BACKGROUND

Glucocorticoid-induced osteoporosis is a leading secondary cause of osteoporosis. Cullin-1 (CUL1) levels are abnormally elevated in patients with osteoporosis, but the underlying mechanism remains unclear. The purpose of this study was to elucidate the mechanism of action of CUL1 in a glucocorticoid (dexamethasone, Dex)-induced osteoporosis model.

METHODS

C57BL/6J mice were intraperitoneally injected with Dex to establish an osteoporosis model. Mouse femur bone injury and bone formation were detected using hematoxylin-eosin or Masson staining. Apoptosis and cell cycle distribution were determined by flow cytometry. Alkaline phosphatase (ALP) activity and calcified nodules were monitored using ALP and Alizarin Red S staining. The molecular mechanism was validated by co-immunoprecipitation (Co-IP) and ubiquitination assays.

RESULTS

CUL1 expression was enhanced in the Dex-induced osteoporosis mouse model. CUL1 silencing moderated the Dex-induced cell proliferation and osteogenesis inhibition. Moreover, CUL1 promoted the ubiquitination and degradation of ASAP1 via the SKP1-CUL1-F-box (SCF)-FBXW7 complex. CUL1 induced apoptosis and repressed osteogenesis by ASAP1. CUL1 silencing alleviated the Dex-induced osteoporosis in mice.

CONCLUSION

CUL1 suppressed osteoblast proliferation and osteogenesis by promoting ASAP1 ubiquitination via the SCF-FBXW7 complex in glucocorticoid-induced osteoporosis.

Post-Translational Modifications in Histones and Their Role in Abiotic Stress Tolerance in Plants

Abiotic stresses profoundly alter plant growth and development, resulting in yield losses. Plants have evolved adaptive mechanisms to combat these challenges, triggering intricate molecular responses to maintain tissue hydration and temperature stability during stress. A pivotal player in this defense is histone modification, governing gene expression in response to diverse environmental cues. Post-translational modifications (PTMs) of histone tails, including acetylation, phosphorylation, methylation, ubiquitination, and sumoylation, regulate transcription, DNA processes, and stress-related traits. This review comprehensively explores the world of PTMs of histones in plants and their vital role in imparting various abiotic stress tolerance in plants. Techniques, like chromatin immune precipitation (ChIP), ChIP-qPCR, mass spectrometry, and Cleavage Under Targets and Tag mentation, have unveiled the dynamic histone modification landscape within plant cells. The significance of PTMs in enhancing the plants' ability to cope with abiotic stresses has also been discussed. Recent advances in PTM research shed light on the molecular basis of stress tolerance in plants. Understanding the intricate proteome complexity due to various proteoforms/protein variants is a challenging task, but emerging single-cell resolution techniques may help to address such challenges. The review provides the future prospects aimed at harnessing the full potential of PTMs for improved plant responses under changing climate change.