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1.
Pharmacol Ther ; 260: 108680, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38878974

RESUMO

Ubiquitin-fold modifier 1 (UFM1) is covalently conjugated to protein substrates via a cascade of enzymatic reactions, a process known as UFMylation. UFMylation orchestrates an array of vital biological functions, including maintaining endoplasmic reticulum (ER) homeostasis, facilitating protein biogenesis, promoting cellular differentiation, regulating DNA damage response, and participating in cancer-associated signaling pathways. UFMylation has rapidly evolved into one of the forefront research areas within the last few years, yet much remains to be uncovered. In this review, first, UFMylation and its cellular functions associated with diseases are briefly introduced. Then, we summarize the proteomic approaches for identifying UFMylation substrates and explore the impact of UFMylation on gene transcription, protein translation, and maintenance of ER homeostasis. Next, we highlight the intricate regulation between UFMylation and two protein degradation pathways, the ubiquitin-proteasome system and the autophagy-lysosome pathway, and explore the potential of UFMylation system as a drug target. Finally, we discuss emerging perspectives in the UFMylation field. This review may provide valuable insights for drug discovery targeting the UFMylation system.

2.
Heliyon ; 10(11): e31431, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38845972

RESUMO

Colorectal cancer is one of the most common malignancies and ranks second in terms of cancer-related mortality worldwide due to its metastasis, drug resistance, and reoccurrence. High-mobility gene group A2 (HMGA2) is overexpressed in colorectal cancer, contributing to the aggressiveness of tumor malignance, and promotes drug resistance in many types of cancer. However, the underlying molecular mechanism of HMGA2 is yet to be elucidated. In this study, we showed that HMGA2 is overexpressed in colorectal cancer tissue, and knockdown of HMGA2 significantly inhibited colorectal cancer cell growth and migratory capability. HMGA2 regulates the cancer cell response to a widely used anti-cancer drug, paclitaxel (PTX). HMGA2 knockdown increased cell death, whereas HMGA2 overexpression decreased cell death after PTX treatment. Furthermore, lower reactive oxygen species (ROS) levels and mitochondrial potential were detected in HMGA2 overexpression cells after PTX treatment. However, HMGA2 knockdown produced the opposite effect. RNA sequencing showed a p53 signaling pathway-dependent regulation in HMGA2 knockdown cells. Combined with p53 inhibitors and HMGA2 knockdown, a synergetic effect of more cell death was observed in colorectal cancer cells after PTX treatment. Thus, we showed that HMGA2 can activate p53 signaling to regulate colorectal cancer cell death after PTX treatment. Altogether, our results reveal novel insights into the molecular mechanisms underlying HMGA2-mediated cancer cell resistance against PTX and highlight the potential of targeting HMGA2 and p53 signaling for the therapeutic investigation of colorectal cancer.

4.
Sheng Wu Gong Cheng Xue Bao ; 40(6): 1963-1971, 2024 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-38914504

RESUMO

Industrial biotechnology is regarded as the most promising technology for sustainable industrial development. The advancement of synthetic biology creates new opportunities and infinite possibilities for the progress of industrial biotechnology. Fermentation engineering is the grab and foothold of the industrialization of all the biotechnologies. Our teaching team optimized the teaching content and innovated the teaching mode to establish a teaching system of synthetic biology matching fermentation engineering. We highlighted the teaching characteristics (telling fermentation story cultivated the craftsmanship spirit; bioeconomic education strengthened the engineering thinking; bioethics and safety education fostered a sense of responsibility), then we summarized and prospected the teaching reform of this course. We believe that the teaching reform of synthetic biology will improve the learning performance of postgraduates, provide a reference for the teaching of synthetic biology in related fields, and promote the development of industrial biotechnology (strengthening the innovation capability in biological manufacturing and cultivating new momentum for bioeconomy).


Assuntos
Biotecnologia , Fermentação , Biologia Sintética , Educação de Pós-Graduação , Ensino , Engenharia Metabólica
5.
J Genet Genomics ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871233

RESUMO

miR-504 plays a pivotal role in the progression of oral cancer. However, the underlying mechanism remains elusive in vivo. Here, we find that miR-504 is significantly down-regulated in oral cancer patients. We generate miR-504 knockout mice (miR-504-/-) using CRISPR/Cas9 technology to investigate its impact on the malignant progression of oral cancer under exposure to 4-Nitroquinoline N-oxide (4NQO). We show that the deletion of miR-504 does not affect phenotypic characteristics, body weight, reproductive performance, or survival in mice, but results in changes in the blood physiological and biochemical indexes of the mice. Moreover, with 4NQO treatment, miR-504-/- mice exhibit more pronounced pathological changes characteristic of oral cancer. RNA-seq shows that the differentially expressed genes observed in samples from miR-504-/- mice with oral cancer are involved in regulating cell metabolism, cytokine activation, and lipid metabolism-related pathways. Additionally, these differentially expressed genes are significantly enriched in lipid metabolism pathways that influence immune cell infiltration within the tumor microenvironment, thereby accelerating tumor development progression. Collectively, our results suggest that knockout of miR-504 accelerates malignant progression in 4NQO-induced oral cancer by regulating tumor cell proliferation and lipid metabolism affecting immune cell infiltration.

6.
Biomark Res ; 12(1): 60, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858750

RESUMO

Acute myeloid leukemia (AML) is the most frequent leukemia in adults with a high mortality rate. Current diagnostic criteria and selections of therapeutic strategies are generally based on gene mutations and cytogenetic abnormalities. Chemotherapy, targeted therapies, and hematopoietic stem cell transplantation (HSCT) are the major therapeutic strategies for AML. Two dilemmas in the clinical management of AML are related to its poor prognosis. One is the inaccurate risk stratification at diagnosis, leading to incorrect treatment selections. The other is the frequent resistance to chemotherapy and/or targeted therapies. Genomic features have been the focus of AML studies. However, the DNA-level aberrations do not always predict the expression levels of genes and proteins and the latter is more closely linked to disease phenotypes. With the development of high-throughput sequencing and mass spectrometry technologies, studying downstream effectors including RNA, proteins, and metabolites becomes possible. Transcriptomics can reveal gene expression and regulatory networks, proteomics can discover protein expression and signaling pathways intimately associated with the disease, and metabolomics can reflect precise changes in metabolites during disease progression. Moreover, omics profiling at the single-cell level enables studying cellular components and hierarchies of the AML microenvironment. The abundance of data from different omics layers enables the better risk stratification of AML by identifying prognosis-related biomarkers, and has the prospective application in identifying drug targets, therefore potentially discovering solutions to the two dilemmas. In this review, we summarize the existing AML studies using omics methods, both separately and combined, covering research fields of disease diagnosis, risk stratification, prognosis prediction, chemotherapy, as well as targeted therapy. Finally, we discuss the directions and challenges in the application of multi-omics in precision medicine of AML. Our review may inspire both omics researchers and clinical physicians to study AML from a different angle.

7.
Acta Pharmacol Sin ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740904

RESUMO

The circadian clock is the inner rhythm of life activities and is controlled by a self-sustained and endogenous molecular clock, which maintains a ~ 24 h internal oscillation. As the core element of the circadian clock, BMAL1 is susceptible to degradation through the ubiquitin-proteasome system (UPS). Nevertheless, scant information is available regarding the UPS enzymes that intricately modulate both the stability and transcriptional activity of BMAL1, affecting the cellular circadian rhythm. In this work, we identify and validate UBR5 as a new E3 ubiquitin ligase that interacts with BMAL1 by using affinity purification, mass spectrometry, and biochemical experiments. UBR5 overexpression induced BMAL1 ubiquitination, leading to diminished stability and reduced protein level of BMAL1, thereby attenuating its transcriptional activity. Consistent with this, UBR5 knockdown increases the BMAL1 protein. Domain mapping discloses that the C-terminus of BMAL1 interacts with the N-terminal domains of UBR5. Similarly, cell-line-based experiments discover that HYD, the UBR5 homolog in Drosophila, could interact with and downregulate CYCLE, the BMAL1 homolog in Drosophila. PER2-luciferase bioluminescence real-time reporting assay in a mammalian cell line and behavioral experiments in Drosophila reveal that UBR5 or hyd knockdown significantly reduces the period of the circadian clock. Therefore, our work discovers a new ubiquitin ligase UBR5 that regulates BMAL1 stability and circadian rhythm and elucidates the underlying molecular mechanism. This work provides an additional layer of complexity to the regulatory network of the circadian clock at the post-translational modification level, offering potential insights into the modulation of the dysregulated circadian rhythm.

8.
Phys Rev Lett ; 132(17): 176302, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38728705

RESUMO

Compared with conventional topological insulator that carries topological state at its boundaries, the higher-order topological insulator exhibits lower-dimensional gapless boundary states at its corners and hinges. Leveraging the form similarity between Schrödinger equation and diffusion equation, research on higher-order topological insulators has been extended from condensed matter physics to thermal diffusion. Unfortunately, all the corner states of thermal higher-order topological insulator reside within the band gap. Another kind of corner state, which is embedded in the bulk states, has not been realized in pure diffusion systems so far. Here, we construct higher-dimensional Su-Schrieffer-Heeger models based on sphere-rod structure to elucidate these corner states, which we term "in-bulk corner states." Because of the anti-Hermitian properties of diffusive Hamiltonian, we investigate the thermal behavior of these corner states through theoretical calculation, simulation, and experiment. Furthermore, we study the different thermal behaviors of in-bulk corner state and in-gap corner state. Our results would open a different gate for diffusive topological states and provide a distinct application for efficient heat dissipation.

9.
Cell Death Dis ; 15(5): 335, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744853

RESUMO

PTENα/ß, two variants of PTEN, play a key role in promoting tumor growth by interacting with WDR5 through their N-terminal extensions (NTEs). This interaction facilitates the recruitment of the SET1/MLL methyltransferase complex, resulting in histone H3K4 trimethylation and upregulation of oncogenes such as NOTCH3, which in turn promotes tumor growth. However, the molecular mechanism underlying this interaction has remained elusive. In this study, we determined the first crystal structure of PTENα-NTE in complex with WDR5, which reveals that PTENα utilizes a unique binding motif of a sequence SSSRRSS found in the NTE domain of PTENα/ß to specifically bind to the WIN site of WDR5. Disruption of this interaction significantly impedes cell proliferation and tumor growth, highlighting the potential of the WIN site inhibitors of WDR5 as a way of therapeutic intervention of the PTENα/ß associated cancers. These findings not only shed light on the important role of the PTENα/ß-WDR5 interaction in carcinogenesis, but also present a promising avenue for developing cancer treatments that target this pathway.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , PTEN Fosfo-Hidrolase , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/química , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/química , Animais , Camundongos , Neoplasias/genética , Neoplasias/patologia , Neoplasias/metabolismo , Proliferação de Células/genética , Progressão da Doença , Ligação Proteica , Linhagem Celular Tumoral , Camundongos Nus , Histona-Lisina N-Metiltransferase/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/química , Domínios Proteicos , Motivos de Aminoácidos
10.
Biotechnol Bioeng ; 121(7): 2163-2174, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38595326

RESUMO

Pathogenic bacterial membrane proteins (MPs) are a class of vaccine and antibiotic development targets with widespread clinical application. However, the inherent hydrophobicity of MPs poses a challenge to fold correctly in living cells. Herein, we present a comprehensive method to improve the soluble form of MP antigen by rationally designing multi-epitope chimeric antigen (ChA) and screening two classes of protein-assisting folding element. The study uses a homologous protein antigen as a functional scaffold to generate a ChA possessing four epitopes from transferrin-binding protein A of Glaesserella parasuis. Our engineered strain, which co-expresses P17 tagged-ChA and endogenous chaperones groEL-ES, yields a 0.346 g/L highly soluble ChA with the property of HPS-positive serum reaction. Moreover, the protein titer of ChA reaches 4.27 g/L with >90% soluble proportion in 5-L bioreactor, which is the highest titer reported so far. The results highlight a timely approach to design and improve the soluble expression of MP antigen in industrially viable applications.


Assuntos
Antígenos de Bactérias , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Reatores Biológicos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Escherichia coli/genética , Escherichia coli/metabolismo , Clostridiales/genética , Clostridiales/metabolismo , Solubilidade
11.
Theranostics ; 14(6): 2345-2366, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646645

RESUMO

Rationale: Primordial follicles are limited in number and cannot be regenerated, dormant primordial follicles cannot be reversed once they enter a growth state. Therefore, the length of the female reproductive lifespan depends on the orderly progression and selective activation of primordial follicles, the mechanism of which remains unclear. Methods: We used human ovarian cortical biopsy specimens, granulosa cells from diminished ovarian reserve (DOR) patients, Hdac6-overexpressing transgenic mouse model, and RNA sequencing to analyze the crucial roles of histone deacetylase 6 (HDAC6) in fertility preservation and primordial follicle activation. Results: In the present study, we found that HDAC6 was highly expressed in most dormant primordial follicles. The HDAC6 expression was reduced accompanying reproductive senescence in human and mouse ovaries. Overexpression of Hdac6 delayed the rate of primordial follicle activation, thereby prolonging the mouse reproductive lifespan. Short-term inhibition of HDAC6 promoted primordial follicle activation and follicular development in humans and mice. Mechanism studies revealed that HDAC6 directly interacted with NGF, reducing acetylation modification of NGF and thereby accelerating its ubiquitination degradation. Consequently, the reduced NGF protein level maintained the dormancy of primordial follicles. Conclusions: The physiological significance of the high expression of HDAC6 in most primordial follicles is to reduce NGF expression and prevent primordial follicle activation to maintain female fertility. Reduced HDAC6 expression increases NGF expression in primordial follicles, activating their development and contributing to reproduction. Our study provides a clinical reference value for fertility preservation.


Assuntos
Desacetilase 6 de Histona , Camundongos Transgênicos , Fator de Crescimento Neural , Folículo Ovariano , Ubiquitinação , Animais , Feminino , Humanos , Camundongos , Acetilação , Células da Granulosa/metabolismo , Desacetilase 6 de Histona/metabolismo , Desacetilase 6 de Histona/genética , Fator de Crescimento Neural/metabolismo , Folículo Ovariano/metabolismo
12.
Acta Pharmacol Sin ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622288

RESUMO

Cancer cells largely rely on aerobic glycolysis or the Warburg effect to generate essential biomolecules and energy for their rapid growth. The key modulators in glycolysis including glucose transporters and enzymes, e.g. hexokinase 2, enolase 1, pyruvate kinase M2, lactate dehydrogenase A, play indispensable roles in glucose uptake, glucose consumption, ATP generation, lactate production, etc. Transcriptional regulation and post-translational modifications (PTMs) of these critical modulators are important for signal transduction and metabolic reprogramming in the glycolytic pathway, which can provide energy advantages to cancer cell growth. In this review we recapitulate the recent advances in research on glycolytic modulators of cancer cells and analyze the strategies targeting these vital modulators including small-molecule inhibitors and microRNAs (miRNAs) for targeted cancer therapy. We focus on the regulation of the glycolytic pathway at the transcription level (e.g., hypoxia-inducible factor 1, c-MYC, p53, sine oculis homeobox homolog 1, N6-methyladenosine modification) and PTMs (including phosphorylation, methylation, acetylation, ubiquitination, etc.) of the key regulators in these processes. This review will provide a comprehensive understanding of the regulation of the key modulators in the glycolytic pathway and might shed light on the targeted cancer therapy at different molecular levels.

14.
World J Gastrointest Surg ; 16(3): 966-973, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38577088

RESUMO

BACKGROUND: Colorectal cavernous hemangioma is a rare vascular malformation resulting in recurrent lower gastrointestinal hemorrhage, and can be misinterpreted as colitis. Surgical resection is currently the mainstay of treatment, with an emphasis on sphincter preservation. CASE SUMMARY: We present details of two young patients with a history of persistent hematochezia diagnosed with colorectal cavernous hemangioma by endoscopic ultrasound (EUS). Cavernous hemangioma was relieved by several EUS-guided lauromacrogol injections and the patients achieved favorable clinical prognosis. CONCLUSION: Multiple sequential EUS-guided injections of lauromacrogol is a safe, effective, cost-efficient, and minimally invasive alternative for colorectal cavernous hemangioma.

15.
Nat Commun ; 15(1): 2169, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461277

RESUMO

Extensive investigations on the moiré magic angle in twisted bilayer graphene have unlocked the emerging field-twistronics. Recently, its optics analogue, namely opto-twistronics, further expands the potential universal applicability of twistronics. However, since heat diffusion neither possesses the dispersion like photons nor carries the band structure as electrons, the real magic angle in electrons or photons is ill-defined for heat diffusion, making it elusive to understand or design any thermal analogue of magic angle. Here, we introduce and experimentally validate the twisted thermotics in a twisted diffusion system by judiciously tailoring thermal coupling, in which twisting an analog thermal magic angle would result in the function switching from cloaking to concentration. Our work provides insights for the tunable heat diffusion control, and opens up an unexpected branch for twistronics -- twisted thermotics, paving the way towards field manipulation in twisted configurations including but not limited to fluids.

16.
Biotechnol J ; 19(3): e2300650, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38479990

RESUMO

S-Adenosyl-L-methionine (SAM) is a substrate for many enzyme-catalyzed reactions and provides methyl groups in numerous biological methylations, and thus has vast applications in the agriculture and medical field. Saccharomyces cerevisiae has been engineered as a platform with significant potential for producing SAM, but the current production has room for improvement. Thus, a method that consists of a series of metabolic engineering strategies was established in this study. These strategies included enhancing SAM synthesis, increasing ATP supply, down-regulating SAM metabolism, and down-regulating competing pathway. After combinatorial metabolic engineering, Bayesian optimization was conducted on the obtained strain C262P6S to optimize the fermentation medium. A final yield of 2972.8 mg·L-1 at 36 h with 29.7% of the L-Met conversion rate in the shake flask was achieved, which was 26.3 times higher than that of its parent strain and the highest reported production in the shake flask to date. This paper establishes a feasible foundation for the construction of SAM-producing strains using metabolic engineering strategies and demonstrates the effectiveness of Bayesian optimization in optimizing fermentation medium to enhance the generation of SAM.


Assuntos
Metionina , S-Adenosilmetionina , Metionina/metabolismo , S-Adenosilmetionina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Engenharia Metabólica/métodos , Teorema de Bayes , Fermentação , Racemetionina/metabolismo
17.
Cerebrovasc Dis ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38301613

RESUMO

BACKGROUND: This research explored the factors influencing early neurological outcomes (ENO) in patients who had vertebrobasilar artery occlusion (VBAO) and received endovascular treatment (EVT), as well as examining the causal influence of ENO on the prognosis of VBAO patients. METHODS: A retrospective review was carried out on patients from 65 Chinese stroke centers, all within 24 hours of the estimated occlusion time. ENO includes early neurological improvement (ENI) and early neurological deterioration (END), defined as a decrease or an increase of at least 4 points in NIHSS score between baseline and 24 hours after EVT. Death within 24 hours after EVT also consider as END. END was further divided into explainable END and unexplainable END (unEND). Independent predictors of ENO and the association between ENO and outcomes in patients with VBAO were determined using center-adjusted analyses. The study developed a multivariate logistic regression model to examine the comparative risk of unEND versus explainable END on the clinical outcomes in VBAO patients. RESULTS: A total of 2257 patients were included. Glasgow Coma Scale (GCS) (OR 1.16, 95% CI 1.03-1.30) and successful reperfusion (OR 1.15, 95% CI 1.02-1.30) were associated with ENI. Baseline NIHSS (OR 0.60, 95% CI 0.53-0.68), successful reperfusion (OR 0.79, 95% CI 0.71-0.89) and puncture to reperfusion time (OR 1.17, 95% CI 1.03-1.33) were associated with END. When examining three-month prognostic indexes, both END and ENI were found to be linked to the three-month outcomes, but in opposite directions. A subgroup analysis of END suggested that unexplained END typically demonstrated a more favorable prognosis compared to explained END, although the prognosis remained generally unfavorable. CONCLUSIONS: ENO, whether they manifested as early improvement or deterioration, were linked to the prognosis of VBAO patients undergoing EVT. The outcomes after unEND were more favorable than those following explained END.

18.
Biomed Pharmacother ; 172: 116259, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38359488

RESUMO

Gastric cancer is a highly metastatic malignant tumor with high morbidity and mortality globally. Recent studies reported that sulfonamide derivatives such as indisulam exhibited inhibitory effects on the viability and migration of cancer cells. However, multiple clinical trials revealed that indisulam did not significantly prevent cancer progression due to metastasis and drug resistance. Therefore, it is necessary to discover new potent derivatives to explore alternative therapeutic strategies. Here, we synthesize multiple indisulam derivatives and examine their inhibitory effects on the viability and migration of gastric cancer cells. Among them, compounds SR-3-65 and WXM-1-170 exhibit better inhibitory effects on the migration of gastric cancer cells than indisulam. Mechanistically, we discover that they could attenuate the PI3K/AKT/GSK-3ß/ß-catenin signaling pathway and lead to the suppression of epithelial-to-mesenchymal transition (EMT)-related transcription factors. The influence of SR-3-65 on the migration of gastric cancer cells is blocked by the PI3K inhibitor LY294002 while SR-3-65 and WXM-1-170 reverse the effect of PI3K activator 740 Y-P on the migration of gastric cancer cells. Molecular docking and molecular dynamics simulation further confirm that PI3K is the target of SR-3-65. Our study unveils a novel mechanism by which SR-3-65 and WXM-1-170 inhibit the migration of gastric cancer cells. Together with the previous discovery, we reveal that subtle structural change in indisulam results in a striking switch on the molecular targets and their associated signaling pathways for the inhibition of the migration of gastric cancer cells. These findings might provide informative insights for the development of targeted therapy for gastric cancer.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular Tumoral , Fosfatidilinositol 3-Quinases/metabolismo , Glicogênio Sintase Quinase 3 beta , Simulação de Acoplamento Molecular , Sulfonamidas
19.
Chin Herb Med ; 16(1): 106-112, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38375049

RESUMO

Objective: Anemoside B4 (AB4), the most abundant triterpenoidal saponin isolated from Pulsatilla chinensis, inhibited influenza virus FM1 or Klebsiella pneumoniae-induced pneumonia. However, the anti-SARS-CoV-2 effect of AB4 has not been unraveled. Therefore, this study aimed to determine the antiviral activity and potential mechanism of AB4 in inhibiting human coronavirus SARS-CoV-2 in vivo and in vitro. Methods: The cytotoxicity of AB4 was evaluated using the Cell Counting Kit-8 (CCK8) assay. SARS-CoV-2 infected HEK293T, HPAEpiC, and Vero E6 cells were used for in vitro assays. The antiviral effect of AB4 in vivo was evaluated by SARS-CoV-2-infected hACE2-IRES-luc transgenic mouse model. Furthermore, label-free quantitative proteomics and bioinformatic analysis were performed to explore the potential antiviral mechanism of action of AB4. Type I IFN signaling-associated proteins were assessed using Western blotting or immumohistochemical staining. Results: The data showed that AB4 reduced the propagation of SARS-CoV-2 along with the decreased Nucleocapsid protein (N), Spike protein (S), and 3C-like protease (3CLpro) in HEK293T cells. In vivo antiviral activity data revealed that AB4 inhibited viral replication and relieved pneumonia in a SARS-CoV-2 infected mouse model. We further disclosed that the antiviral activity of AB4 was associated with the enhanced interferon (IFN)-ß response via the activation of retinoic acid-inducible gene I (RIG-1) like receptor (RLP) pathways. Additionally, label-free quantitative proteomic analyses discovered that 17 proteins were significantly altered by AB4 in the SARS-CoV-2 coronavirus infections cells. These proteins mainly clustered in RNA metabolism. Conclusion: Our results indicated that AB4 inhibited SARS-CoV-2 replication through the RLR pathways and moderated the RNA metabolism, suggesting that it would be a potential lead compound for the development of anti-SARS-CoV-2 drugs.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38381313

RESUMO

Sisomicin is a broad-spectrum aminoglycoside antibiotic and is the precursor of netilmicin and plazomicin. However, the fermentation level of sisomicin is still low compared with other antibiotics, which restricts the application of sisomicin and its derivatives. In this study, to improve sisomicin production, breeding of high-yielding sisomicin strains was conducted with chemical mutagenesis using Micromonospora inyoensis OG-1 (titer, 1042 U·mL-1) as the starting strain. Protoplast preparation was conducted under optimal conditions, and protoplast mutagenesis was performed with a suitable concentration of diethyl sulfate. Subsequently, a high-yielding and genetically stable strain (H6-32) was obtained by screening, with a sisomicin titer of 1486 U·mL-1 (an increase of 42.6%). Finally, carbon and nitrogen sources were optimized to further improve sisomicin production, and a sisomicin titer of 1780 U·mL-1 was ultimately obtained by controlling the dissolved oxygen level at 30% in a 5-L fermenter, which to the best of our knowledge is the highest reported titer ever achieved by fermentation. Comparative genome analysis showed that a total of 13 genes in the genome of the mutant strain H6-32 were mutated compared to the original strain. This study not only provides a reference for further breeding of high-yielding strains and fermentation optimization, but also enhances our understanding of sisomicin production.

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