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1.
Nucleic Acids Res ; 52(10): 5529-5548, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38512058

RESUMO

The process of induced pluripotent stem cells (iPSCs) reprogramming involves several crucial events, including the mesenchymal-epithelial transition (MET), activation of pluripotent genes, metabolic reprogramming, and epigenetic rewiring. Although these events intricately interact and influence each other, the specific element that regulates the reprogramming network remains unclear. Dux, a factor known to promote totipotency during the transition from embryonic stem cells (ESC) to 2C-like ESC (2CLC), has not been extensively studied in the context of iPSC reprogramming. In this study, we demonstrate that the modification of H3K18la induced by Dux overexpression controls the metabolism-H3K18la-MET network, enhancing the efficiency of iPSC reprogramming through a metabolic switch and the recruitment of p300 via its C-terminal domain. Furthermore, our proteomic analysis of H3K18la immunoprecipitation experiment uncovers the specific recruitment of Brg1 during reprogramming, with both H3K18la and Brg1 being enriched on the promoters of genes associated with pluripotency and epithelial junction. In summary, our study has demonstrated the significant role of Dux-induced H3K18la in the early reprogramming process, highlighting its function as a potent trigger. Additionally, our research has revealed, for the first time, the binding of Brg1 to H3K18la, indicating its role as a reader of histone lactylation.


Assuntos
Reprogramação Celular , Transição Epitelial-Mesenquimal , Histonas , Proteínas de Homeodomínio , Células-Tronco Pluripotentes Induzidas , Fatores de Transcrição , Animais , Humanos , Camundongos , Reprogramação Celular/genética , DNA Helicases/metabolismo , DNA Helicases/genética , Transição Epitelial-Mesenquimal/genética , Histonas/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
2.
Small ; 20(24): e2307602, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38150669

RESUMO

Transparent aerogels are ideal candidates for thermally insulating windows, solar thermal receivers, electronics, etc. However, they are usually prepared via energy-consuming supercritical drying and show brittleness and low tensile strength, significantly restricting their practical applications. It remains a great challenge to prepare transparent aerogels with high tensile strength and toughness. Herein, biomimetic transparent tough cellulose nanofiber-based nanocomposite aerogels with a layered nanofibrous structure are achieved by vacuum-assisted self-assembly combined with ambient pressure drying. The nacre-like layered homogeneous nanoporous structures can reduce light scattering and effectively transfer stress and prevent stress concentration under external forces. The aerogels exhibit an attractive combination of excellent transparency and hydrophobicity, high compressive and tensile strengths, high toughness, excellent machinability, thermal superinsulation, and wide working temperature range (-196 to 230 °C). It is demonstrated that they can be used for superinsulating windows of buildings and high-efficient thermal management for electronics and human bodies. In addition, a prototype of transparent flexible aerogel-based triboelectric nanogenerator is developed. This work provides a promising pathway toward transparent tough porous materials for energy saving/harvesting, thermal management, electronics, sensors, etc.

3.
Environ Sci Technol ; 58(1): 459-467, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38152050

RESUMO

Atmospheric phosphorus is a vital nutrient for ecosystems whose sources and fate are still debated in the fragile Himalayan region, hindering our comprehension of its local ecological impact. This study provides novel insights into atmospheric phosphorus based on the study of total suspended particulate matter at the Qomolangma station. Contrary to the prevailing assumptions, we show that biomass burning (BB), not mineral dust, dominates total dissolved phosphorus (TDP, bioavailable) deposition in this arid region, especially during spring. While total phosphorus is mainly derived from dust (77% annually), TDP is largely affected by the transport of regional biomass-burning plumes from South Asia. During BB pollution episodes, TDP causing springtime TDP fluxes alone accounts for 43% of the annual budget. This suggests that BB outweighs dust in supplying bioavailable phosphorus, a critical nutrient, required to sustain Himalayas' ecological functions. Overall, this first-hand field evidence refines the regional and global phosphorus budget by demonstrating that BB emission, while still unrecognized, is a significant source of P, even in the remote mountains of the Himalayas. It also reveals the heterogeneity of atmospheric phosphorus deposition in that region, which will help predict changes in the impacted ecosystems as the deposition patterns vary.


Assuntos
Poluentes Atmosféricos , Biomassa , Poluentes Atmosféricos/análise , Fósforo , Ecossistema , Himalaia , Poeira/análise , Material Particulado/análise , Minerais , Proteínas de Ligação a DNA , Monitoramento Ambiental , Aerossóis/análise
4.
Yi Chuan ; 46(4): 290-305, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38632092

RESUMO

The tumor suppressor programmed cell death 4 (PDCD4) is downregulated in various tumor tissues indicating poor prognosis. PDCD4 is the first protein found to resist tumor transformation, invasion, and metastasis by inhibiting translation. The functions of PDCD4 dependent on its structures are affected by extracellular signals. It regulates tumor-related proteins through a variety of mechanisms, especially involved in two major signaling pathways, PI3K-Akt-mTOR and MAPK. By analyzing the relationship between the structures, functions and diseases of PDCD4, this review summarizes the roles of PDCD4 in several physiological processes and diseases such as apoptosis, autophagy, tumor, and inflammation in recent years, thereby providing insights for the study of the signaling pathways of PDCD4 and related proteins and the treatment of diseases targeting them.


Assuntos
Proteínas Reguladoras de Apoptose , Fosfatidilinositol 3-Quinases , Proteínas de Ligação a RNA , Apoptose , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Humanos , Transdução de Sinais/genética
5.
Nat Commun ; 15(1): 392, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195718

RESUMO

Highly stretchable porous materials are promising for flexible electronics but their fabrication is a great challenge. Herein, several kinds of highly stretchable conductive porous elastomers with low or negative Poisson's ratios are achieved by uniaxial, biaxial, and triaxial hot-pressing strategies. The reduced graphene oxide/polymer nanocomposite elastomers with folded porous structures obtained by uniaxial hot pressing exhibit high stretchability up to 1200% strain. Furthermore, the meta-elastomers with reentrant porous structures combining high biaxial (or triaxial) stretchability and negative Poisson's ratios are achieved by biaxial (or triaxial) hot pressing. The resulting elastomer-based wearable strain sensors exhibit an ultrawide response range (0-1200%). The materials can be applied for smart thermal management and electromagnetic interference shielding, which are achieved by regulating the porous microstructures via stretching. This work provides a versatile strategy to highly stretchable and negative-Poisson-ratio porous materials with promising features for various applications such as flexible electronics, thermal management, electromagnetic shielding, and energy storage.

6.
Cell Stem Cell ; 31(1): 127-147.e9, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38141611

RESUMO

Our understanding of pluripotency remains limited: iPSC generation has only been established for a few model species, pluripotent stem cell lines exhibit inconsistent developmental potential, and germline transmission has only been demonstrated for mice and rats. By swapping structural elements between Sox2 and Sox17, we built a chimeric super-SOX factor, Sox2-17, that enhanced iPSC generation in five tested species: mouse, human, cynomolgus monkey, cow, and pig. A swap of alanine to valine at the interface between Sox2 and Oct4 delivered a gain of function by stabilizing Sox2/Oct4 dimerization on DNA, enabling generation of high-quality OSKM iPSCs capable of supporting the development of healthy all-iPSC mice. Sox2/Oct4 dimerization emerged as the core driver of naive pluripotency with its levels diminished upon priming. Transient overexpression of the SK cocktail (Sox+Klf4) restored the dimerization and boosted the developmental potential of pluripotent stem cells across species, providing a universal method for naive reset in mammals.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Humanos , Camundongos , Ratos , Animais , Suínos , Macaca fascicularis/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Reprogramação Celular , Fatores de Transcrição SOXB1/metabolismo , Diferenciação Celular , Mamíferos/metabolismo
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