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Epigenetic modifications play an important role in cellular senescence, and enhancer of zeste homolog 2 (EZH2) is a key methyltransferase involved in epigenetic remodeling in multiple myeloma (MM) cells. We have previously demonstrated that GSK126, a specific EZH2 inhibitor, exhibits anti-MM therapeutic efficacy and safety in vivo and in vitro; however, its specific mechanism remains unclear. This study shows that GSK126 induces cellular senescence in MM, which is characterized by the accumulation of senescence-associated heterochromatin foci (SAHF) and p21, and increased senescence-associated β galactosidase activity. Furthermore, EZH2 is inhibited in ribonucleotide reductase regulatory subunit M2 (RRM2)-overexpressing OCI-MY5 and RPMI-8226 cells. RRM2 overexpression inhibits the methyltransferase function of EZH2 and promotes its degradation through the ubiquitin-proteasome pathway, thereby inducing cellular senescence. In this senescence model, Lamin B1, a key component of the nuclear envelope and a marker of senescence, does not decrease but instead undergoes aberrant accumulation. Meanwhile, phosphorylation of extracellular signal-regulated protein kinase (ERK1/2) is significantly increased. The inhibition of ERK1/2 phosphorylation in turn partially restores Lamin B1 level and alleviates senescence. These findings suggest that EZH2 inhibition increases Lamin B1 level and induces senescence by promoting ERK1/2 phosphorylation. These data indicate that EZH2 plays an important role in MM cellular senescence and provide insights into the relationships among Lamin B1, p-ERK1/2, and cellular senescence.

Background: Aging is associated with significant structural and functional changes in the spleen, leading to immunosenescence, yet the detailed effects on splenic vascular endothelial cells (ECs) and their immunomodulatory roles are not fully understood. In this study, a single-cell RNA (scRNA) atlas of EC transcriptomes from young and aged mouse spleens was constructed to reveal age-related molecular changes, including increased inflammation and reduced vascular development and also the potential interaction between splenic endothelial cells and immune cells. Results: Ten clusters of splenic endothelial cells were identified. DEGs analysis across different EC clusters revealed the molecular changes with aging, showing the increase in the overall inflammatory microenvironment and the loss in vascular development function of aged ECs. Notably, four EC clusters with immunological functions were identified, suggesting an Endothelial-to-Immune-like Cell Transition (EndICLT) potentially driven by aging. Pseudotime analysis of the Immunology4 cluster further indicated a possible aging-induced transitional state, potentially initiated by Ctss gene activation. Finally, the effects of aging on cell signaling communication between different EC clusters and immune cells were analyzed. Conclusions: This comprehensive atlas elucidates the complex interplay between ECs and immune cells in the aging spleen, offering new insights into endothelial heterogeneity, reprogramming, and the mechanisms of immunosenescence. [ABSTRACT FROM AUTHOR]

The brown planthopper, Nilaparvata lugens (Hemiptera: Delphacidae) (BPH), is a major, regionally migratory pest of rice in Asia. Despite intensive migratory studies, the seasonal migratory pattern of this species in the year-round breeding region (i.e. Hainan Island) remains largely unknown. To understand the migration dynamics, we conducted relevant research based on BPH light trap catches on Hainan in 2017–2022. Results showed that the occurrence dynamics of BPH in Hainan oscillated in different years and seasons. Overall, there are 4 migration peak periods on Hainan, with outbound peak periods in April–May and August–September and inbound peak periods in June and October. Trajectory and wind fields showed that in August–September, Hainan had complex meteorological conditions, and the outbound paths of BPH were variable, mainly landing in southeastern Guangxi and southwestern Guangdong. In contrast, April–May was influenced by southeasterly winds, with a wider outbound range and a further distance, landing along northeastern Vietnam from west to east toward Guangxi and Guangdong areas with time. Wind-rain fields, trajectory, and hydrogen isotope showed that in June, southwesterly winds transported BPH northward from the Indochina peninsula, where it was hindered by rainfall in the Leizhou Peninsula area and the migrants will be "rained out" into Hainan. Identically, in October, the interactions between northeasterly winds and rainfall belts on the southwest shore of Hainan increased the opportunities for BPH to migrate southward to reach Hainan. Our results suggest that Hainan is not only an important source of BPH migrating from East Asia but also plays the role of a bridge. [ABSTRACT FROM AUTHOR]

A novel 2D/2D g-C3N4/BiOCl (CN/BOC) heterojunction photocatalyst was synthesized by grinding appropriate amounts of CN, Bi(NO3)3·5H2O, glacial acetic acid and KCl at room temperature. The porous CN nanosheets not only facilitate the in situ nucleation and growth of BOC to form thin nanosheets and constitute an intimate contact interface, but also introduce more oxygen vacancies (OVs) in the grinding process. The 2D/2D CN/BOC heterojunction had a good interface and generates a built-in electric field, which can improve the separation of e− and h+. The synergistic effect of the heterostructure and OVs made the photocatalyst have significantly better performance than CN and BOC alone under visible light. The most efficient CN/BOC-5 could achieve a tetracycline (TC) degradation rate of 89.8% within 2 h, which was 1.9 and 1.2 times faster than CN and BOC, respectively. It catalyzed the reduction of CO2 to CO at a rate of 2.00 μ mol h−1 g−1, 1.1 and 3.2 times faster than CN and BOC, respectively. The mechanism for the photocatalysis of CN/BOC-5 was revealed. It was confirmed that the efficiency of photo-induced carrier separation and visible-light photo-absorption were both considerably increased by the synergistic interaction between OVs and 2D/2D heterojunction. This research may open up new possibilities for the logical design of efficient photocatalysts through combining 2D/2D heterojunctions with OVs for environmental remediation. Highlights: •Grinding synthesis of 2D/2D BiOCl/g-C3N4 heterostructure with oxygen vacancies (OVs). •The synergistic effect of heterostructure and OVs enabled excellent photoactivity. •Efficient photocatalytic degradation of organic pollutants and reduction of CO2. [ABSTRACT FROM AUTHOR]

The vegetable leafminer (Liriomyza sativae [Burgess]) is a highly polyphagous pest that threatens vegetables and horticultural plants. Although sexual communication is a key component of the animal behavioral repertoire, the mechanism underlying sexual communication in L. sativae remains to be elucidated. Here, we used laser vibrometry to characterize the vibrational signals emitted by L. sativae during pair formation. By emitting trains of vibrational pulses (male calling) the male initiated communication on the host plant. The female then became immobile and responded to the male calling by emitting replies (female replies), which in turn triggered male replies consisting of a rapid series of chirps and trills. If the female replied, a continuous exchange of male and female replies ensued, representing a duet. In playback trials, a playback signal caused responses from the opposite sex. Moreover, scanning electron microscopy revealed vibration‐producing stridulatory organs in both male and female individuals. The files in males were more developed than those in females, and older male specimens had more signs of abrasion. The results provide new insight into the mating biology of L. sativae. [ABSTRACT FROM AUTHOR]