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3.
Bioact Mater ; 28: 196-205, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37250864

RESUMO

Mechanical force is crucial in the whole process of embryonic development. However, the role of trophoblast mechanics during embryo implantation has rarely been studied. In this study, we constructed a model to explore the effect of stiffness changes in mouse trophoblast stem cells (mTSCs) on implantation: microcarrier was prepared by sodium alginate using a droplet microfluidics system, and mTSCs were attached to the microcarrier surface with laminin modifications, called T(micro). Compared with the spheroid, formed by the self-assembly of mTSCs (T(sph)), we could regulate the stiffness of the microcarrier, making the Young's modulus of mTSCs (367.70 ± 79.81 Pa) similar to that of the blastocyst trophoblast ectoderm (432.49 ± 151.90 Pa). Moreover, T(micro) contributes to improve the adhesion rate, expansion area and invasion depth of mTSCs. Further, T(micro) was highly expressed in tissue migration-related genes due to the activation of the Rho-associated coiled-coil containing protein kinase (ROCK) pathway at relatively similar modulus of trophoblast. Overall, our study explores the embryo implantation process with a new perspective, and provides theoretical support for understanding the effect of mechanics on embryo implantation.

4.
J Med Chem ; 66(9): 6070-6081, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-36892138

RESUMO

Proteolysis-targeting chimera (PROTAC) technology has emerged as a potential strategy to degrade "undruggable" proteins in recent years. Nrf2, an aberrantly activated transcription factor in cancer, is generally considered undruggable as lacking active sites or allosteric pockets. Here, we constructed the chimeric molecule C2, which consists of an Nrf2-binding element and a CRBN ligand, as a first-in-class Nrf2 degrader. Surprisingly, C2 was found to selectively degrade an Nrf2-MafG heterodimer simultaneously via the ubiquitin-proteasome system. C2 impeded Nrf2-ARE transcriptional activity significantly and improved the sensitivity of NSCLC cells to ferroptosis and therapeutic drugs. The degradation character of ARE-PROTACs suggests that the PROTAC hijacking the transcription element of TFs could achieve co-degradation of the transcription complex.


Assuntos
Fator 2 Relacionado a NF-E2 , Quimera de Direcionamento de Proteólise , Regulação da Expressão Gênica , Fator 2 Relacionado a NF-E2/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Fator de Transcrição MafG/metabolismo
5.
Science ; 377(6609): 967-975, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-36007034

RESUMO

Chromosome engineering has been attempted successfully in yeast but remains challenging in higher eukaryotes, including mammals. Here, we report programmed chromosome ligation in mice that resulted in the creation of new karyotypes in the lab. Using haploid embryonic stem cells and gene editing, we fused the two largest mouse chromosomes, chromosomes 1 and 2, and two medium-size chromosomes, chromosomes 4 and 5. Chromatin conformation and stem cell differentiation were minimally affected. However, karyotypes carrying fused chromosomes 1 and 2 resulted in arrested mitosis, polyploidization, and embryonic lethality, whereas a smaller fused chromosome composed of chromosomes 4 and 5 was able to be passed on to homozygous offspring. Our results suggest the feasibility of chromosome-level engineering in mammals.


Assuntos
Fusão Gênica Artificial , Edição de Genes , Cariótipo , Translocação Genética , Animais , Fusão Gênica Artificial/métodos , Cromatina/química , Células-Tronco Embrionárias , Edição de Genes/métodos , Haploidia , Camundongos , Mitose
6.
Acta Pharm Sin B ; 12(7): 2990-3005, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35865099

RESUMO

The proteolysis targeting chimeras (PROTACs) technology has been rapidly developed since its birth in 2001, attracting rapidly growing attention of scientific institutes and pharmaceutical companies. At present, a variety of small molecule PROTACs have entered the clinical trial. However, as small molecule PROTACs flourish, non-small molecule PROTACs (NSM-PROTACs) such as peptide PROTACs, nucleic acid PROTACs and antibody PROTACs have also advanced considerably over recent years, exhibiting the unique characters beyond the small molecule PROTACs. Here, we briefly introduce the types of NSM-PROTACs, describe the advantages of NSM-PROTACs, and summarize the development of NSM-PROTACs so far in detail. We hope this article could not only provide useful insights into NSM-PROTACs, but also expand the research interest of NSM-PROTACs.

7.
J Chromatogr Sci ; 60(2): 173-178, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34021565

RESUMO

OBJECTIVE: To establish an ultra-high performance liquid chromatography (UPLC) method for simultaneous determination of umbelliferonel, nodakenin, psoralen, xanthotoxin and bergapten contents in Peucedanum decursivum Radix. METHODS: The analysis was achieved on a Symmetry®C18 column (4.6 mm × 250 mm, 5 µm), with acetonitrile and water as the mobile phase in gradient elution mode. The column temperature was maintained at 30°C, with flow rate 1.0 mL·min-1. The injection volume of sample was 10 µL. The ultraviolet detection wavelength was set at the maximum absorption wavelength 325 nm for umbelliferonel and nodakenin, 259 nm for psoralen, xanthotoxin and bergapten, respectively. RESULTS: The five kinds of coumarins in Peucedanum decursivum Radix were separated well and the linear relation was obtained (R2 ≥ 0.9998). The average recoveries were 101.31, 105.27, 90.85, 106.42 and 90.19%, respectively, with Relative standard deviation (RSD) 3.07, 3.17, 1.62, 2.53 and 4.54%, respectively. CONCLUSIONS: The established method was accurate and feasible, which could be used as the basis of quality control of Peucedanum decursivum Radix.


Assuntos
Cumarínicos , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Cumarínicos/análise , Medicamentos de Ervas Chinesas/análise , Raízes de Plantas/química , Controle de Qualidade
8.
Sci Adv ; 7(48): eabi6178, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34818044

RESUMO

While mouse remains the most popular model, the conservation of parental-to-embryonic epigenetic transition across mammals is poorly defined. Through analysis of oocytes and early embryos in human, bovine, porcine, rat, and mouse, we revealed remarkable species-specific innovations as no single animal model fully recapitulates the human epigenetic transition. In rodent oocytes, transcription-dependent DNA methylation allows methylation of maternal imprints but not intergenic paternal imprints. Unexpectedly, prevalent DNA hypermethylation, paralleled by H3K36me2/3, also occurs in nontranscribed regions in porcine and bovine oocytes, except for megabase-long "CpG continents (CGCs)" where imprinting control regions preferentially reside. Broad H3K4me3 and H3K27me3 domains exist in nonhuman oocytes, yet only rodent H3K27me3 survives beyond genome activation. Coincidently, regulatory elements preferentially evade H3K27me3 in rodent oocytes, and failure to do so causes aberrant embryonic gene repression. Hence, the diverse mammalian innovations of parental-to-embryonic transition center on a delicate "to-methylate-or-not" balance in establishing imprints while protecting other regulatory regions.

9.
Molecules ; 26(5)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804392

RESUMO

Deep eutectic solvents (DESs) are green organic solvents that have broad prospects in the extraction of effective components of traditional Chinese medicine. This work employed the quantitative analysis of multi-components by a single marker (QAMS) method to quantitatively determine the six effective components of glycyrrhizic acid, liquiritin, isoliquiritin apioside, liquiritigenin, isoliquiritin, and glycyrrhetinic acid in Glycyrrhiza uralensis, which was used for comprehensive evaluation of the optimal extraction process by DESs. First, Choline Chloride: Lactic Acid (ChCl-LA, molar ratio 1:1) was selected as the most suitable DES by comparing the extraction yields of different DESs. Second, the extraction protocol was investigated by extraction time, extraction temperature, liquid-to-material ratio, molar ratio, and ultrasonic power. The Box-Behnken design (BBD) combined with response surface methodology (RSM) was used to investigate the optimal DES conditions. The result showed that the best DES system was 1.3-butanediol/choline chloride (ChCl) with the molar ratio of 4:1. The optimal extraction process of licorice was 20 mL/g, the water content was 30%, and the extraction time was 41 min. The comprehensive impact factor (z) was 0.92. At the same time, it was found that the microstructure of the residue extracted by the eutectic solvent was more severely damaged than the residue after the traditional solvent extraction through observation under an electron microscope. The DES has the characteristics of high efficiency and rapidity as an extraction solution.


Assuntos
Butileno Glicóis/química , Colina/química , Flavonoides/análise , Flavonoides/isolamento & purificação , Glycyrrhiza uralensis/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão
10.
J Anal Methods Chem ; 2021: 6655572, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33532111

RESUMO

OBJECTIVE: To establish a method for simultaneous determination of liquiritin, liquiritigenin, and isoliquiritinin glycyrrhizin using hydrogen nuclear magnetic resonance quantitative technology (1H-qNMR). Methodology. Deuterated dimethyl sulfoxide was used as the solvent, and dichloromethane was used as the internal standard. The probe temperature was 298.0 K, the pulse sequence was Zg30, the number of scans was 16, and relaxation delay (D1) was 10 s. Quantitative characteristic signal peaks were δ 4.891∼4.878 ppm, δ 8.187∼8.172 ppm, and δ 6.790∼6.776 ppm for liquiritin, isoliquiritin, and liquiritigenin, respectively. RESULTS: The experimental result showed that the content of flavonoids in Licorice, from Chifeng, Inner Mongolia, was the highest. CONCLUSION: In this study, a new method for determination of three flavonoids in Licorice using 1H-qNMR was established. This experimental method has the advantages of accuracy, efficiency, and economy. It lays a foundation for the study on the determination of flavonoids content in licorice by proton nuclear magnetic resonance spectroscopy.

11.
Cell Stem Cell ; 27(2): 315-325.e5, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32559418

RESUMO

Successful cloning by somatic cell nuclear transfer (SCNT) requires overcoming significant epigenetic barriers. Genomic imprinting is not generally regarded as such a barrier, although H3K27me3-dependent imprinting is differentially distributed in E6.5 epiblast and extraembryonic tissues. Here we report significant enhancement of SCNT efficiency by deriving somatic donor cells carrying simultaneous monoallelic deletion of four H3K27me3-imprinted genes from haploid mouse embryonic stem cells. Quadruple monoallelic deletion of Sfmbt2, Jade1, Gab1, and Smoc1 normalized H3K27me3-imprinted expression patterns and increased fibroblast cloning efficiency to 14% compared with a 0% birth rate from wild-type fibroblasts while preventing the placental and body overgrowth defects frequently observed in cloned animals. Sfmbt2 deletion was the most effective of the four individual gene deletions in improving SCNT. These results show that lack of H3K27me3 imprinting in somatic cells is an epigenetic barrier that impedes post-implantation development of SCNT embryos and can be overcome by monoallelic imprinting gene deletions in donor cells.


Assuntos
Histonas , Técnicas de Transferência Nuclear , Animais , Clonagem de Organismos , Desenvolvimento Embrionário/genética , Feminino , Impressão Genômica , Histonas/metabolismo , Camundongos , Gravidez , Proteínas Repressoras
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