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Genomic instability is not only a hallmark of senescent cells but also a key factor driving cellular senescence, and replication stress is the main source of genomic instability. Defective prelamin A processing caused by lamin A/C (LMNA) or zinc metallopeptidase STE24 (ZMPSTE24) gene mutations results in premature aging. Although previous studies have shown that dysregulated lamin A interferes with DNA replication and causes replication stress, the relationship between lamin A dysfunction and replication stress remains largely unknown. Here, an increase in baseline replication stress and genomic instability is found in prelamin A‐expressing cells. Moreover, prelamin A confers hypersensitivity of cells to exogenous replication stress, resulting in decreased cell survival and exacerbated genomic instability. These effects occur because prelamin A promotes MRE11‐mediated resection of stalled replication forks. Fanconi anemia (FA) proteins, which play important roles in replication fork maintenance, are downregulated by prelamin A in a retinoblastoma (RB)/E2F‐dependent manner. Additionally, prelamin A inhibits the activation of the FA pathway upon replication stress. More importantly, FA pathway downregulation is an upstream event of p53‐p21 axis activation during the induction of prelamin A expression. Overall, these findings highlight the critical role of FA pathway dysfunction in driving replication stress‐induced genomic instability and cellular senescence in prelamin A‐expressing cells. [ABSTRACT FROM AUTHOR]

Chlorine-doped MoS 2 quantum dots (Cl-MoS 2 QDs) embedded in a SiO 2 molecularly imprinted polymer (Cl-MoS 2 QDs@SiO 2 @MIP) have been successfully synthesized and can be used for highly selective and sensitive optosensing of quercetin. The novel environmentally friendly sensor integrated the advantages of the Cl-MoS 2 QDs and MIP, high sensitivity and specific recognition for quercetin. The as-fabricated sensor is used to detect trace amounts of quercetin, and its fluorescence intensity showed a good linear decline with the increasing concentration of quercetin from 2 ng mL -1 to 200 ng mL -1 with a detection limit of 1.2 ng mL -1 (S/N = 3). The Cl-MoS 2 QDs@SiO 2 @MIP probe was employed to assay the content of quercetin of real onion extract with good performance, which is in fine agreement with the result obtained by high performance liquid chromatography. The developed Cl-MoS 2 QDs@SiO 2 @MIP sensor exhibits promising potential in the detection of quercetin.

An activated carbon-supported Cu/ZnO catalyst (CCZ-AE-ox) was successfully obtained by the ammonia evaporation method for the hydrogenation of carbon dioxide to methanol, and the surface properties of the catalyst post-calcination and reduction were investigated. Activated carbon facilitated the increased dispersion of the loaded metals, which promote the CO 2 space-time yield (STY) of methanol and turnover frequency (TOF) on the active sites. Furthermore, the factors affecting the catalyst in the hydrogenation of CO 2 to methanol were in-depth investigated. The larger surface area and higher CO 2 adsorption capacity are found to make possible the main attributions of the superior activity of the CCZ-AE-ox catalyst., Competing Interests: The authors declare that there are no known competing financial interests or personal relationships which have appeared to affect the work reported herein., (This journal is © The Royal Society of Chemistry.)

MoS 2 has attracted great attention as a prospective electrocatalyst for generating hydrogen via water electrolysis due to its abundant and inexpensive sources. However, bulk MoS 2 has weak electrocatalytic activity because of its low electrical conductivity and few edge-active sites. Controllable synthesis of MoS 2 with ultrasmall size or complex morphology may be an available strategy to boost its conductivity and edge-active sites. Herein, a facile single-precursor strategy was developed to prepare nanoscale MoS 2 with various morphologies, including quantum dots, nanorods, nanoribbons, and nanosheets. In-depth studies show that the formation of MoS 2 with various shapes is determined by both kinetic and thermodynamic factors such as reaction time and temperature. Electrocatalytic tests reveal that MoS 2 quantum dots have high electrocatalytic performance with a low overpotential of 255 mV and a small Tafel slope of 66 mV dec -1 due to the abundant exposed active edges and excellent intrinsic conductivity., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)