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1.
Nature ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898275

RESUMO

Naturally occurring (native) sugars and carbohydrates contain numerous hydroxyl groups of similar reactivity1,2. Chemists, therefore, rely typically on laborious, multi-step protecting-group strategies3 to convert these renewable feedstocks into reagents (glycosyl donors) to make glycans. The direct transformation of native sugars to complex saccharides remains a notable challenge. Here we describe a photoinduced approach to achieve site- and stereoselective chemical glycosylation from widely available native sugar building blocks, which through homolytic (one-electron) chemistry bypasses unnecessary hydroxyl group masking and manipulation. This process is reminiscent of nature in its regiocontrolled generation of a transient glycosyl donor, followed by radical-based cross-coupling with electrophiles on activation with light. Through selective anomeric functionalization of mono- and oligosaccharides, this protecting-group-free 'cap and glycosylate' approach offers straightforward access to a wide array of metabolically robust glycosyl compounds. Owing to its biocompatibility, the method was extended to the direct post-translational glycosylation of proteins.

2.
FASEB J ; 38(1): e23372, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38102977

RESUMO

Embryo vitrification is a standard procedure in assisted reproductive technology. Previous studies have shown that frozen embryo transfer is associated with an elevated risk of adverse maternal and neonatal outcomes. This study aimed to explore the effects of mouse blastocyst vitrification on the phenotype of vitrified-warmed blastocysts, their intrauterine and postnatal development, and the long-term metabolic health of the derived offspring. The vitrified-warmed blastocysts (IVF + VT group) exhibited reduced mitochondrial activity, increased apoptotic levels, and decreased cell numbers when compared to the fresh blastocysts (IVF group). Implantation rates, live pup rates, and crown-rump length at E18.5 were not different between the two groups. However, there was a significant decrease in fetal weight and fetal/placental weight ratio in the IVF + VT group. Furthermore, the offspring of the IVF + VT group at an age of 36 weeks had reduced whole energy consumption, impaired glucose and lipid metabolism when compared with the IVF group. Notably, RNA-seq results unveiled disturbed hepatic gene expression in the offspring from vitrified-warmed blastocysts. This study revealed the short-term negative impacts of vitrification on embryo and fetal development and the long-term influence on glucose and lipid metabolism that persist from the prenatal stage into adulthood in mice.


Assuntos
Criopreservação , Vitrificação , Gravidez , Feminino , Animais , Camundongos , Criopreservação/métodos , Placenta , Desenvolvimento Embrionário , Blastocisto , Glucose , Estudos Retrospectivos
3.
J Virol ; 97(5): e0045923, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37097154

RESUMO

Numerous studies have illustrated that the Seneca Valley virus (SVV) shows sufficient oncolytic efficacy targeting small cell lung cancer (SCLC). However, the therapeutics of nonsmall cell lung carcinoma (NSCLC, accounts for 85% of lung cancer cases) using oncolytic virus have been resisting due to the filtration of neutralizing antibody and limited reproduction capacity. Here, we employed structural biology and reverse genetics to optimize novel oncolytic SVV mutants (viral receptor-associated mutant SVV-S177A and viral antigenic peptide-related variant SVV-S177A/P60S) with increased infectivity and lower immunogenicity. The results of the NSCLC-bearing athymic mouse model demonstrated that wild-type (wt) SVV-HB extended the median overall survival (mOS) from 11 days in the PBS group to 19 days. Notably, the newly discovered mutations significantly (P < 0.001) prolonged the mOS from 11 days in the control cohort to 23 days in the SVV-S177A cohort and the SVV-S177A/P60S cohort. Taken together, we present a structure-guided genetic modification strategy for oncolytic SVV optimization and provide a candidate for developing oncolytic viral therapy against nonsensitive NSCLC. IMPORTANCE Nonsmall cell lung cancer (NSCLC) accounts for approximately 85% of lung cancer cases (more than 1.85 million cases with 1.48 million deaths in 2020). In the present study, two novel oncolytic SVV mutants modified based on structural biology and reverse genetics (viral receptor-associated mutant SVV-S177A and viral antigenic peptide-related mutant SVV-S177A/P60S) with increased infectivity or lower immunogenicity significantly (P < 0.001) prolonged the mOS from 11 days in the control cohort to 23 days in the SVV-S177A cohort and the SVV-S177A/P60S cohort in the NSCLC-bearing athymic mouse model, which may provide the direction for modifying SVV to improve the effect of oncolysis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Picornaviridae , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Pulmão , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Camundongos Nus , Picornaviridae/genética
4.
Biomacromolecules ; 25(5): 3001-3010, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38598264

RESUMO

Glycosylation is a valuable tool for modulating protein solubility; however, the lack of reliable research strategies has impeded efficient progress in understanding and applying this modification. This study aimed to bridge this gap by investigating the solubility of a model glycoprotein molecule, the carbohydrate-binding module (CBM), through a two-stage process. In the first stage, an approach involving chemical synthesis, comparative analysis, and molecular dynamics simulations of a library of glycoforms was employed to elucidate the effect of different glycosylation patterns on solubility and the key factors responsible for the effect. In the second stage, a predictive mathematical formula, innovatively harnessing machine learning algorithms, was derived to relate solubility to the identified key factors and accurately predict the solubility of the newly designed glycoforms. Demonstrating feasibility and effectiveness, this two-stage approach offers a valuable strategy for advancing glycosylation research, especially for the discovery of glycoforms with increased solubility.


Assuntos
Aprendizado de Máquina , Simulação de Dinâmica Molecular , Solubilidade , Glicosilação , Glicoproteínas/química
5.
Nature ; 564(7734): 136-140, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30487604

RESUMO

Postnatal growth of mammalian oocytes is accompanied by a progressive gain of DNA methylation, which is predominantly mediated by DNMT3A, a de novo DNA methyltransferase1,2. Unlike the genome of sperm and most somatic cells, the oocyte genome is hypomethylated in transcriptionally inert regions2-4. However, how such a unique feature of the oocyte methylome is determined and its contribution to the developmental competence of the early embryo remains largely unknown. Here we demonstrate the importance of Stella, a factor essential for female fertility5-7, in shaping the oocyte methylome in mice. Oocytes that lack Stella acquire excessive DNA methylation at the genome-wide level, including in the promoters of inactive genes. Such aberrant hypermethylation is partially inherited by two-cell-stage embryos and impairs zygotic genome activation. Mechanistically, the loss of Stella leads to ectopic nuclear accumulation of the DNA methylation regulator UHRF18,9, which results in the mislocalization of maintenance DNA methyltransferase DNMT1 in the nucleus. Genetic analysis confirmed the primary role of UHRF1 and DNMT1 in generating the aberrant DNA methylome in Stella-deficient oocytes. Stella therefore safeguards the unique oocyte epigenome by preventing aberrant de novo DNA methylation mediated by DNMT1 and UHRF1.


Assuntos
DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA , Epigênese Genética , Oócitos/metabolismo , Proteínas Repressoras/metabolismo , Animais , Proteínas Estimuladoras de Ligação a CCAAT , Linhagem Celular , Núcleo Celular/metabolismo , Proteínas Cromossômicas não Histona , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , Desenvolvimento Embrionário , Feminino , Genoma/genética , Humanos , Camundongos , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/genética , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética , Ubiquitina-Proteína Ligases , Zigoto/metabolismo
6.
J Biomech Eng ; 146(7)2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38329431

RESUMO

Cardiomyocytes are viscoelastic and key determinants of right ventricle (RV) mechanics. Intracellularly, microtubules are found to impact the viscoelasticity of isolated cardiomyocytes or trabeculae; whether they contribute to the tissue-level viscoelasticity is unknown. Our goal was to reveal the role of the microtubule network in the passive anisotropic viscoelasticity of the healthy RV. Equibiaxial stress relaxation tests were conducted in healthy RV free wall (RVFW) under early (6%) and end (15%) diastolic strain levels, and at sub- and physiological stretch rates. The viscoelasticity was assessed at baseline and after the removal of microtubule network. Furthermore, a quasi-linear viscoelastic (QLV) model was applied to delineate the contribution of microtubules to the relaxation behavior of RVFW. After removing the microtubule network, RVFW elasticity and viscosity were reduced at the early diastolic strain level and in both directions. The reduction in elasticity was stronger in the longitudinal direction, whereas the degree of changes in viscosity were equivalent between directions. There was insignificant change in RVFW viscoelasticity at late diastolic strain level. Finally, the modeling showed that the tissue's relaxation strength was reduced by the removal of the microtubule network, but the change was present only at a later time scale. These new findings suggest a critical role of cytoskeleton filaments in RVFW passive mechanics in physiological conditions.


Assuntos
Ventrículos do Coração , Coração , Viscosidade , Diástole , Microtúbulos , Elasticidade , Estresse Mecânico
7.
Angew Chem Int Ed Engl ; 63(26): e202402140, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38650440

RESUMO

Alkylamines form the backbone of countless nitrogen-containing small molecules possessing desirable biological properties. Despite advances in amine synthesis through transition metal catalysis and photoredox chemistry, multicomponent reactions that leverage inexpensive materials to transform abundant chemical feedstocks into three-dimensional α-substituted alkylamines bearing complex substitution patterns remain scarce. Here, we report the design of a catalyst-free electroreductive manifold that merges amines, carbonyl compounds and carbon-based radical acceptors under ambient conditions without rigorous exclusion of air and moisture. Key to this aminative carbofunctionalization process is the chemoselective generation of nucleophilic α-amino radical intermediates that readily couple with electrophilic partners, providing straightforward access to architecturally intricate alkylamines and drug-like scaffolds which are inaccessible by conventional means.

8.
J Gen Virol ; 104(3)2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36947577

RESUMO

Seneca Valley virus (SVV, also known as Senecavirus A), an oncolytic virus, is a nonenveloped, positive-strand RNA virus and the sole member of the genus Senecavirus within the family Picornaviridae. The mechanisms of SVV entry into cells are currently almost unknown. In the present study, we found that SVV entry into HEK293T cells is acidic pH-dependent by using ammonium chloride (NH4Cl) and chloroquine, both of which could inhibit SVV infection. We confirmed that dynamin II is required for SVV entry by using dynasore, silencing the dynamin II protein, or expressing the dominant-negative (DN) K44A mutant of dynamin II. Then, we discovered that chlorpromazine (CPZ) treatment or knockdown of the clathrin heavy chain (CLTC) protein significantly inhibited SVV infection. In addition, overexpression of CLTC promoted SVV infection. Caveolin-1 and membrane cholesterol were also required for SVV endocytosis. Notably, utilizing genistein, EIPA or nocodazole, we observed that macropinocytosis and microtubules are not involved in SVV entry. Furthermore, overexpression of the Rab7 and Rab9 proteins but not the Rab5 or Rab11 proteins promoted SVV infection. The findings were further validated by the knockdown of four Rabs and Lamp1 proteins, indicating that after internalization, SVV is transported from late endosomes to the trans-Golgi network (TGN) or lysosomes, respectively, eventually releasing its RNA into the cytosol from the lysosomes. Our findings concretely revealed SVV endocytosis mechanisms in HEK293T cells and provided an insightful theoretical foundation for further research into SVV oncolytic mechanisms.


Assuntos
Dinamina II , Picornaviridae , Humanos , Células HEK293 , Endocitose , Endossomos , Lisossomos , Internalização do Vírus
9.
Biochem Biophys Res Commun ; 670: 36-46, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37271038

RESUMO

Physiological high shear stress (HSS), a frictional force generated by flowing blood, is essential for endothelial homeostasis under normal physiological conditions. HSS suppresses atherosclerosis by inhibiting endothelial inflammation. However, the molecular mechanisms underlying this process have not been fully elucidated. Here, we report that HSS downregulated the mRNA and protein levels of ras homolog family member J (RHOJ) in endothelial cells (ECs). Silencing endogenous RHOJ expression decreased the mRNA and protein levels of proinflammatory vascular cell adhesion molecule 1 (VCAM-1) and intercellular cell adhesion molecule 1 (ICAM-1) in ECs, leading to a reduction in monocyte adhesion to ECs. Conversely, the overexpression of RHOJ had the opposite effect. RNA-sequencing analysis uncovered several differentially expressed genes (such as yes-associated protein 1 (YAP1),heme oxygenase-1 (HO1), and monocyte chemoattractant protein-1 (MCP1)) and pathways (such as nuclear factor-kappa B (NF-κB), fluid shear stress and atherosclerosis, and cell adhesion pathways) as RHOJ targets. Additionally, HSS was observed to alleviate endothelial inflammation by inhibiting RHOJ expression. Finally, methylated RNA immunoprecipitation sequencing (MeRIP-seq) illustrated that fluid shear stress regulates RHOJ expression in an N6-methyladenosine (m6A)-dependent manner. Mechanistically, the RNA m6A writer, methyltransferase 3 (METTL3), and the RNA m6A readers, YTH N6-methyladenosine RNA-binding protein F 3 (YTHDF3) and YTH N6-methyladenosine RNA-binding protein C 1/2 (YTHDC1/2), are involved in this process. Taken together, our data demonstrate that HSS-induced downregulation of RHOJ contributes to endothelial homeostasis by suppressing endothelial inflammation and that RHOJ inhibition in ECs is a promising therapeutic strategy for endothelial dysfunction.


Assuntos
Aterosclerose , Células Endoteliais , Humanos , Células Endoteliais/metabolismo , Inflamação/genética , Inflamação/metabolismo , RNA/metabolismo , RNA Mensageiro/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Proteínas de Ligação a RNA/metabolismo , Metiltransferases/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo
10.
Arch Virol ; 168(3): 99, 2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36871102

RESUMO

Equid herpesvirus 8 (EHV-8), also known as asinine herpesvirus type 3 (AHV-3), can cause severe respiratory disease, abortion in mares, and neurological disorders. There is limited information on the prevalence of EHV-8 in donkeys in China. In this study, we investigated EHV-8 infection in donkeys using PCR, resulting in the identification of a field strain, termed EHV-8 SD2020113, which was isolated using RK-13 cells and characterized by high-throughput sequencing and transmission electron microscopy. Our data indicated that 38.7% (457/1180) of donkeys showed the presence of EHV-8 in blood samples. Analysis of the ORF70 gene showed the highest similarity (99.8-99.9% identity) to EHV-8 IR/2015/40 (MF431614.1) and SDLC66 (MW816102), and, in phylogenetic analysis, it clustered with EHV-8 SDLC66 from China. The findings of this study indicate that EHV-8 is likely to represent a threat to the donkey industry, and breeders and veterinarians who care for donkey farms should be aware of this.


Assuntos
Equidae , Varicellovirus , Gravidez , Cavalos , Animais , Feminino , Filogenia , China , Fazendas , Sequenciamento de Nucleotídeos em Larga Escala
11.
J Immunol ; 207(1): 189-199, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34183365

RESUMO

Seneca Valley virus (SVV), a newly emerging virus belonging to the Picornaviridae family, has caused vesicular disease in the swine industry. However, the molecular mechanism of viral pathogenesis remains poorly understood. This study revealed that SVV infection could induce pyroptosis in SK6 cells in a caspase-dependent and -independent manner. SVV may inhibit caspase-1 activation at late infection because of 3Cpro cleavage of NLRP3, which counteracted pyroptosis activation. Further study showed that 3Cpro targeted porcine gasdermin D (pGSDMD) for cleavage through its protease activity. 3Cpro cleaved porcine GSDMD (pGSDMD) at two sites, glutamine 193 (Q193) and glutamine 277 (Q277), and Q277 was close to the caspase-1-induced pGSDMD cleavage site. pGSDMD1-277 triggered cell death, which was similar to N-terminal fragment produced by caspase-1 cleavage of pGSDMD, and other fragments exhibited no significant inhibitory effects on cellular activity. Ectopic expression of pGSDMD converted 3Cpro-induced apoptosis to pyroptosis in 293T cells. Interestingly, 3Cpro did not cleave mouse GSDMD or human GSDMD. And, both pGSDMD and pGSDMD1-277 exhibited bactericidal activities in vivo. Nevertheless, pGSDMD cannot kill bacteria in vitro. Taken together, our results reveal a novel pyroptosis activation manner produced by viral protease cleavage of pGSDMD, which may provide an important insight into the pathogenesis of SVV and cancer therapy.


Assuntos
Proteases Virais 3C/imunologia , Proteínas de Ligação a Fosfato/imunologia , Picornaviridae/enzimologia , Animais , Células Cultivadas , Células HEK293 , Humanos , Piroptose/imunologia , Suínos
12.
Biochem Biophys Res Commun ; 591: 124-129, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34815077

RESUMO

Mendelian susceptibility to mycobacterial disease (MSMD) is a rare monogenetic disease, which is characterized by susceptibility to some weakly virulent mycobacteria. Here, we explored the pathogenic genes and molecular mechanisms of MSMD patients. We recruited three patients diagnosed with MSMD from two families. Two novel mutations (c.1228A > G, p.K410E and c.2071A > G, p.M691V) in STAT1 gene were identified from two families. The translocation of K410E mutant STAT1 protein into nucleus was not affected. The binding ability between gamma-activating sequence (GAS) and K410E mutant STAT1 protein was significantly reduced, which will reduce the interaction between STAT1 protein with the promoters of target genes. The M691V mutant STAT1 protein cannot translocate into the nucleus after IFN-γ stimulation, which will affect the STAT1 protein form gamma-activating factors (GAF) and bind the GAS in the promoter region of downstream target genes. Taken together, our results showed that the mutation of K410E led to impaired binding of STAT1 to target DNA, and the mutation of M691V prevented the transport of STAT1 into the nucleus, which led to MSMD. Together, we identified two novel mutations (c.1228A > G, p.K410E and c.2071A > G, p.M691V) in STAT1 gene in MSMD patients, and deciphered the molecular mechanism of MSMD caused by STAT1 mutations.


Assuntos
Predisposição Genética para Doença , Mutação/genética , Infecções por Mycobacterium/genética , Infecções por Mycobacterium/microbiologia , Fator de Transcrição STAT1/genética , Sequência de Aminoácidos , Sequência de Bases , Núcleo Celular/metabolismo , DNA/metabolismo , Feminino , Células HEK293 , Células HeLa , Humanos , Masculino , Proteínas Mutantes/química , Proteínas Mutantes/genética , Linhagem , Ligação Proteica , Domínios Proteicos , Transporte Proteico , Fator de Transcrição STAT1/química , Fator de Transcrição STAT1/metabolismo , Frações Subcelulares/metabolismo
13.
Biol Reprod ; 107(1): 183-195, 2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35526125

RESUMO

Epigenetic regulations play a central role in governing the embryo development and somatic cell reprogramming. Taking advantage of recent advances in low-input sequencing techniques, researchers have uncovered a comprehensive view of the epigenetic landscape during rapid transcriptome transitions involved in the cell fate commitment. The well-organized epigenetic reprogramming also highlights the essential roles of specific epigenetic regulators to support efficient regulation of transcription activity and chromatin remodeling. This review briefly introduces the recent progress in the molecular dynamics and regulation mechanisms implicated in mouse early embryo development and somatic cell reprograming, as well as the multi-omics regulatory mechanisms of totipotency mediated by several key factors, which provide valuable resources for further investigations on the complicated regulatory network in essential biological events.


Assuntos
Reprogramação Celular , Epigênese Genética , Animais , Diferenciação Celular/genética , Reprogramação Celular/genética , Montagem e Desmontagem da Cromatina , Desenvolvimento Embrionário/genética , Camundongos
14.
Cell Tissue Res ; 390(3): 367-383, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36201050

RESUMO

T helper 22 (Th22) cells have been implicated in diabetic retinopathy (DR), but it remains unclear whether Th22 cells involve in the pathogenesis of DR. To investigate the role of Th22 cells in DR mice, the animal models were established by intraperitoneal injection of STZ and confirmed by fundus fluorescein angiography and retinal haematoxylin-eosin staining. IL-22BP was administered by intravitreal injection. IL-22 level was measured by ELISA in vivo and in vitro. The expression of IL-22Rα1 in the retina was assessed by immunofluorescence. We assessed GFAP, VEGF, ICAM-1, inflammatory-associated factors and the integrity of blood-retinal barrier in control, DR, IL-22BP, and sham group. Müller cells were co-cultured with Th22 cells, and the expression of the above proteins was measured by immunoblotting. Plasmid transfection technique was used to silence Act1 gene in Müller cells. Results in vivo and in vitro indicated that Th22 cells infiltrated into the DR retinal and IL-22Rα1 expressed in Müller cells. Th22 cells promoted Müller cells activation and inflammatory factor secretion by secreting IL-22 compared with high-glucose stimulation alone. In addition, IL-22BP ameliorated the pathological alterations of the retina in DR. Inhibition of the inflammatory signalling cascade through Act1 knockdown alleviated DR-like pathology. All in all, the results suggested that Th22 cells infiltrated into the retina and secreted IL-22 in DR, and then IL-22 binding with IL-22Rα1 activated the Act1/TRAF6 signal pathway, and promoted the inflammatory of Müller cells and involved the pathogenesis of DR.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Camundongos , Animais , Células Ependimogliais/patologia , Fator 6 Associado a Receptor de TNF/metabolismo , Diabetes Mellitus Experimental/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Retina/metabolismo
15.
Opt Express ; 30(26): 47836-47846, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558702

RESUMO

Entanglement concentration is a critical technique to prevent degraded fidelity and security in long-distance quantum communication. We propose novel practical entanglement concentration protocols (ECPs) for less-entangled Bell and Greenberger-Horne-Zeilinger states with unknown parameters by solely using simple linear optics. We avoid the need for the post-selection principles or photon-number-resolving detectors to identify the parity-check measurement completely by orchestrating auxiliary time degree of freedom, and the success of ECPs is exactly heralded by the detection signatures without destroying the incident qubits. Additionally, the outting incident photons kept are in the maximally entangled or the less-entangled state, and the success probability can be increased by recycling the latter. The heralded and the basic linear optical elements make our practical ECPs are accessible to experimental investigation with current technology.

16.
Virol J ; 19(1): 10, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991640

RESUMO

BACKGROUND: Equine herpesvirus-8 (EHV-8) is one of the most economically significant viruses that infect mammals of the genus Equus worldwide, which cause severe respiratory diseases and abortion in horses. However, there is no report of abortion caused by EHV-8 in donkeys. CASE PRESENTATION: The present case report is about a 4-year-old donkey having an abortion and showing a serious respiratory issue on the 296th day of pregnancy. Bacteriological and molecular tests were used to screen possible bacterial/viral pathogens to detect the etiological agent. Salmonella abortus equi, EHV-1, EHV-4, and EAV were all negative in the current study. EHV-8, on the other hand, was the only agent that was isolated and identified. CONCLUSIONS: This was for the first time that EHV-8 had been isolated from a donkey in China. EHV-8 infection can cause abortion in donkeys; therefore, veterinarians and breeders should be aware of it.


Assuntos
Infecções por Herpesviridae , Herpesvirus Equídeo 1 , Doenças dos Cavalos , Varicellovirus , Animais , China , Equidae , Feminino , Infecções por Herpesviridae/veterinária , Doenças dos Cavalos/diagnóstico , Cavalos , Gravidez
17.
J Pineal Res ; 72(1): e12778, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34726796

RESUMO

Increasing evidence suggests that in vitro fertilization (IVF) may be associated with an increased risk of developing obesity and metabolic diseases later in life in the offspring. Notably, the addition of melatonin to culture medium may improve embryo development and prevent cardiovascular dysfunction in IVF adult mice. This study aimed to determine if melatonin supplementation in the culture medium can reverse impaired glucose metabolism in IVF mice offspring and the underlying mechanisms. Blastocysts used for transfer were generated by natural mating (control group) or IVF with or without melatonin (10-6  M) supplementation (mIVF and IVF group, respectively) in clinical-grade culture media. Here, we first report that IVF decreased hepatic expression of Fbxl7, which was associated with impaired glucose metabolism in mice offspring. Melatonin addition reversed the phenotype by up-regulating the expression of hepatic Fbxl7. In vitro experiments showed that Fbxl7 enhanced the insulin signaling pathway by degrading RhoA through ubiquitination and was up-regulated by transcription factor Foxa2. Specific knockout of Fbxl7 in the liver of adult mice, through tail intravenous injection of recombinant adeno-associated virus, impaired glucose tolerance, while overexpression of hepatic Fbxl7 significantly improved glucose tolerance in adult IVF mice. Thus, the data suggest that Fbxl7 plays an important role in maintaining glucose metabolism of mice, and melatonin supplementation in the culture medium may rescue the long-term risk of metabolic diseases in IVF offspring.


Assuntos
Melatonina , Animais , Blastocisto , Meios de Cultura , Suplementos Nutricionais , Fertilização in vitro , Glucose , Melatonina/farmacologia , Camundongos
18.
Bioorg Med Chem ; 65: 116757, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35504209

RESUMO

Polycyclic aromatic systems have been considered good biological probes, but some may also be good scaffolds for drug development. In this study, a series of benzobis(imidazole) derivatives were identified as STAT3 signal inhibitors, among which compound 24 showed significant inhibition of IL-6 induced JAK/STAT3 signalling pathway activation. Moreover, 24 inhibited cancer cell growth and migration, and induced cell apoptosis as well as cycle arrest in human hepatocellular carcinoma cells (HepG2) and oesophageal carcinoma cells (EC109). Compound 24 also displayed obvious antitumor activity in a mouse HepG2 cell xenograft tumor model without affecting the body weight. These results confirmed that 24 was a potential STAT3 signal inhibitor with certain antitumor activity.


Assuntos
Neoplasias Hepáticas , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Imidazóis , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Nus , Fosforilação , Fator de Transcrição STAT3/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Nature ; 537(7621): 558-562, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27626379

RESUMO

Histone modifications have critical roles in regulating the expression of developmental genes during embryo development in mammals. However, genome-wide analyses of histone modifications in pre-implantation embryos have been impeded by the scarcity of the required materials. Here, by using a small-scale chromatin immunoprecipitation followed by sequencing (ChIP-seq) method, we map the genome-wide profiles of histone H3 lysine 4 trimethylation (H3K4me3) and histone H3 lysine 27 trimethylation (H3K27me3), which are associated with gene activation and repression, respectively, in mouse pre-implantation embryos. We find that the re-establishment of H3K4me3, especially on promoter regions, occurs much more rapidly than that of H3K27me3 following fertilization, which is consistent with the major wave of zygotic genome activation at the two-cell stage. Furthermore, H3K4me3 and H3K27me3 possess distinct features of sequence preference and dynamics in pre-implantation embryos. Although H3K4me3 modifications occur consistently at transcription start sites, the breadth of the H3K4me3 domain is a highly dynamic feature. Notably, the broad H3K4me3 domain (wider than 5 kb) is associated with higher transcription activity and cell identity not only in pre-implantation development but also in the process of deriving embryonic stem cells from the inner cell mass and trophoblast stem cells from the trophectoderm. Compared to embryonic stem cells, we found that the bivalency (that is, co-occurrence of H3K4me3 and H3K27me3) in early embryos is relatively infrequent and unstable. Taken together, our results provide a genome-wide map of H3K4me3 and H3K27me3 modifications in pre-implantation embryos, facilitating further exploration of the mechanism for epigenetic regulation in early embryos.


Assuntos
Blastocisto/metabolismo , Cromatina/metabolismo , Histonas/química , Histonas/metabolismo , Lisina/metabolismo , Regiões Promotoras Genéticas , Zigoto/metabolismo , Animais , Cromatina/genética , Imunoprecipitação da Cromatina , Células-Tronco Embrionárias/metabolismo , Epigênese Genética , Feminino , Fertilização , Genoma/genética , Masculino , Metilação , Camundongos , Sítio de Iniciação de Transcrição
20.
Nature ; 537(7621): 553-557, 2016 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-27626382

RESUMO

Histone modifications are fundamental epigenetic regulators that control many crucial cellular processes. However, whether these marks can be passed on from mammalian gametes to the next generation is a long-standing question that remains unanswered. Here, by developing a highly sensitive approach, STAR ChIP-seq, we provide a panoramic view of the landscape of H3K4me3, a histone hallmark for transcription initiation, from developing gametes to post-implantation embryos. We find that upon fertilization, extensive reprogramming occurs on the paternal genome, as H3K4me3 peaks are depleted in zygotes but are readily observed after major zygotic genome activation at the late two-cell stage. On the maternal genome, we unexpectedly find a non-canonical form of H3K4me3 (ncH3K4me3) in full-grown and mature oocytes, which exists as broad peaks at promoters and a large number of distal loci. Such broad H3K4me3 peaks are in contrast to the typical sharp H3K4me3 peaks restricted to CpG-rich regions of promoters. Notably, ncH3K4me3 in oocytes overlaps almost exclusively with partially methylated DNA domains. It is then inherited in pre-implantation embryos, before being erased in the late two-cell embryos, when canonical H3K4me3 starts to be established. The removal of ncH3K4me3 requires zygotic transcription but is independent of DNA replication-mediated passive dilution. Finally, downregulation of H3K4me3 in full-grown oocytes by overexpression of the H3K4me3 demethylase KDM5B is associated with defects in genome silencing. Taken together, these data unveil inheritance and highly dynamic reprogramming of the epigenome in early mammalian development.


Assuntos
Alelos , Metilação de DNA , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Inativação Gênica , Histonas/metabolismo , Lisina/metabolismo , Animais , Reprogramação Celular/genética , Imunoprecipitação da Cromatina , Ilhas de CpG/genética , Replicação do DNA , Proteínas de Ligação a DNA/metabolismo , Feminino , Fertilização/genética , Genoma/genética , Histonas/química , Histona Desmetilases com o Domínio Jumonji/metabolismo , Masculino , Metilação , Camundongos , Oócitos/metabolismo , Regiões Promotoras Genéticas , Análise de Sequência de DNA , Iniciação da Transcrição Genética , Zigoto/metabolismo
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