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1.
Development ; 150(21)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37781892

RESUMO

Spermatogenesis begins when cell fate-committed prospermatogonia migrate to the basement membrane and initiate spermatogenesis in response to retinoic acid (RA) in the neonatal testis. The underlying cellular and molecular mechanisms in this process are not fully understood. Here, we report findings on the involvement of a cancer/testis antigen, PRAMEL1, in the initiation and maintenance of spermatogenesis. By analyzing mouse models with either global or conditional Pramel1 inactivation, we found that PRAMEL1 regulates the RA responsiveness of the subtypes of prospermatogonia in the neonatal testis, and affects their homing process during the initiation of spermatogenesis. Pramel1 deficiency led to increased fecundity in juvenile males and decreased fecundity in mature males. In addition, Pramel1 deficiency resulted in a regional Sertoli cell-only phenotype during the first round of spermatogenesis, which was rescued by administration of the RA inhibitor WIN18,446, suggesting that PRAMEL1 functions as an inhibitor of RA signaling in germ cells. Overall, our findings suggest that PRAMEL1 fine-tunes RA signaling, playing a crucial role in the proper establishment of the first and subsequent rounds of spermatogenesis.


Assuntos
Espermatogênese , Tretinoína , Masculino , Camundongos , Animais , Tretinoína/farmacologia , Tretinoína/metabolismo , Espermatogênese/genética , Espermatogônias/metabolismo , Testículo/metabolismo , Transdução de Sinais , Células de Sertoli/metabolismo
2.
Cytokine ; 179: 156623, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38685155

RESUMO

Systemic lupus erythematosus (SLE) is a connective tissue disorder that affects various body systems. Both the innate and adaptive immunity contribute to the onset and progression of SLE. The main mechanism of SLE is an excessive immune response of immune cells to autoantigens, which leads to systemic inflammation and inflammation-induced organ damage. Notably, a subset of innate immune cells known as innate lymphoid cells (ILCs) has recently emerged. ILCs are pivotal in the early stages of infection; participate in immune responses, inflammation, and tissue repair; and regulate the immune function of the body by resisting pathogens and regulating autoimmune inflammation and metabolic homeostasis. Thus, ILCs dysfunction can lead to autoimmune diseases. This review discusses the maturation of ILCs, the potential mechanisms by which ILCs exacerbate SLE pathogenesis, and their contributions to organ inflammatory deterioration in SLE.


Assuntos
Imunidade Inata , Lúpus Eritematoso Sistêmico , Linfócitos , Animais , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Inflamação/patologia , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos/imunologia
3.
Bioorg Med Chem Lett ; 101: 129653, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360420

RESUMO

Gene-encoded aldehyde tag technology has been widely utilized in protein bioorthogonal chemistry and biotechnological application. Herein, we report utilization of the promiscuous rSAM cyclophane synthase SjiB involved in triceptide biosynthesis as a dedicated and highly efficient formylglycine synthase. The new aldehyde tag sequence in this system, YQSSI, is biosynthetically orthogonal to the known aldehyde tag (C/S)x(P/A)xR. The potential use of SjiB/YQSSI aldehyde tag system was further validated in fluorescent labelling of model proteins.


Assuntos
Aldeídos , Ciclofanos , Proteínas
4.
Cell Biol Toxicol ; 40(1): 12, 2024 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-38340268

RESUMO

V-type immunoglobulin domain-containing suppressor of T-cell activation (VISTA), a novel negative checkpoint regulator, plays an essential role in allergic pulmonary inflammation in mice. Treatment with a VISTA agonistic antibody could significantly improve asthma symptoms. Thus, for allergic asthma treatment, VISTA targeting may be a compelling approach. In this study, we examined the functional mechanism of VISTA in allergic pulmonary inflammation and screened the FDA-approved drugs for VISTA agonists. By using mass cytometry (CyTOF), we found that VISTA deficiency primarily increased lung macrophage infiltration in the OVA-induced asthma model, accompanied by an increased proportion of M1 macrophages (CD11b+F4/80+CD86+) and a decreased proportion of M2 macrophages (CD11b+F4/80+CD206+). Further in vitro studies showed that VISTA deficiency promoted M1 polarization and inhibited M2 polarization of bone marrow-derived macrophages (BMDMs). Importantly, we discovered baloxavir marboxil (BXM) as a VISTA agonist by virtual screening of FDA-approved drugs. The surface plasmon resonance (SPR) assays revealed that BXM (KD = 1.07 µM) as well as its active form, baloxavir acid (BXA) (KD = 0.21 µM), could directly bind to VISTA with high affinity. Notably, treatment with BXM significantly ameliorated asthma symptoms, including less lung inflammation, mucus secretion, and the generation of Th2 cytokines (IL-5, IL-13, and IL-4), which were dramatically attenuated by anti-VISTA monoclonal antibody treatment. BXM administration also reduced the pulmonary infiltration of M1 macrophages and raised M2 macrophages. Collectively, our study indicates that VISTA regulates pulmonary inflammation in allergic asthma by regulating macrophage polarization and baloxavir marboxil, and an old drug might be a new treatment for allergic asthma through targeting VISTA.


Assuntos
Asma , Dibenzotiepinas , Pneumonia , Piridonas , Triazinas , Animais , Camundongos , Asma/tratamento farmacológico , Asma/metabolismo , Morfolinas/farmacologia , Morfolinas/uso terapêutico
5.
Acta Pharmacol Sin ; 45(4): 738-750, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38097716

RESUMO

Myocardial hypertrophy is a pathological thickening of the myocardium which ultimately results in heart failure. We previously reported that zonisamide, an antiepileptic drug, attenuated pressure overload-caused myocardial hypertrophy and diabetic cardiomyopathy in murine models. In addition, we have found that the inhibition of proteasome activates glycogen synthesis kinase 3 (GSK-3) thus alleviates myocardial hypertrophy, which is an important anti-hypertrophic strategy. In this study, we investigated whether zonisamide prevented pressure overload-caused myocardial hypertrophy through suppressing proteasome. Pressure overload-caused myocardial hypertrophy was induced in mice by trans-aortic constriction (TAC) surgery. Two days after the surgery, the mice were administered zonisamide (10, 20, 40 mg·kg-1·d-1, i.g.) for four weeks. We showed that zonisamide administration significantly mitigated impaired cardiac function. Furthermore, zonisamide administration significantly inhibited proteasome activity as well as the expression levels of proteasome subunit beta types (PSMB) of the 20 S proteasome (PSMB1, PSMB2 and PSMB5) and proteasome-regulated particles (RPT) of the 19 S proteasome (RPT1, RPT4) in heart tissues of TAC mice. In primary neonatal rat cardiomyocytes (NRCMs), zonisamide (0.3 µM) prevented myocardial hypertrophy triggered by angiotensin II (Ang II), and significantly inhibited proteasome activity, proteasome subunits and proteasome-regulated particles. In Ang II-treated NRCMs, we found that 18α-glycyrrhetinic acid (18α-GA, 2 mg/ml), a proteasome inducer, eliminated the protective effects of zonisamide against myocardial hypertrophy and proteasome. Moreover, zonisamide treatment activated GSK-3 through inhibiting the phosphorylated AKT (protein kinase B, PKB) and phosphorylated liver kinase B1/AMP-activated protein kinase (LKB1/AMPKα), the upstream of GSK-3. Zonisamide treatment also inhibited GSK-3's downstream signaling proteins, including extracellular signal-regulated kinase (ERK) and GATA binding protein 4 (GATA4), both being the hypertrophic factors. Collectively, this study highlights the potential of zonisamide as a new therapeutic agent for myocardial hypertrophy, as it shows potent anti-hypertrophic potential through the suppression of proteasome.


Assuntos
Anticonvulsivantes , Bloqueadores dos Canais de Cálcio , Cardiomegalia , Quinase 3 da Glicogênio Sintase , Complexo de Endopeptidases do Proteassoma , Zonisamida , Animais , Camundongos , Ratos , Proteínas Quinases Ativadas por AMP/metabolismo , Cardiomegalia/tratamento farmacológico , Quinase 3 da Glicogênio Sintase/farmacologia , Camundongos Endogâmicos C57BL , Miócitos Cardíacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Zonisamida/farmacologia , Zonisamida/uso terapêutico , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico
6.
BMC Vet Res ; 20(1): 100, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468314

RESUMO

BACKGROUND: Salmonella enteritidis (SE) is a major zoonotic pathogen and causes infections in a variety of hosts. The development of novel vaccines for SE is necessary to eradicate this pathogen. Genetically engineered attenuated live vaccines are more immunogenic and safer. Thus, to develop a live attenuated Salmonella vaccine, we constructed a cheV gene deletion strain of SE (named ΔcheV) and investigated the role of cheV in the virulence of SE. First, the ability to resist environmental stress in vitro, biofilm formation capacity, drug resistance and motility of ΔcheV were analyzed. Secondly, the bacterial adhesion, invasion, intracellular survival assays were performed by cell model. Using a mouse infection model, an in vivo virulence assessment was conducted. To further evaluate the mechanisms implicated by the reduced virulence, qPCR analysis was utilized to examine the expression of the strain's major virulence genes. Finally, the immune protection rate of ΔcheV was evaluated using a mouse model. RESULTS: Compared to C50336, the ΔcheV had significantly reduced survival ability under acidic, alkaline and thermal stress conditions, but there was no significant difference in survival under oxidative stress conditions. There was also no significant change in biofilm formation ability, drug resistance and motility. It was found that the adhesion ability of ΔcheV to Caco-2 cells remained unchanged, but the invasion ability and survival rate in RAW264.7 cells were significantly reduced. The challenge assay results showed that the LD50 values of C50336 and ΔcheV were 6.3 × 105 CFU and 1.25 × 107 CFU, respectively. After the deletion of the cheV gene, the expression levels of fimD, flgG, csgA, csgD, hflK, lrp, sipA, sipB, pipB, invH, mgtC, sodC, rfbH, xthA and mrr1 genes were significantly reduced. The live attenuated ΔcheV provided 100% protection in mice against SE infection. CONCLUSION: All the results confirmed that the deletion of the cheV gene reduces the virulence of SE and provides significant immune protection in mice, indicating that ΔcheV could be potential candidates to be explored as live-attenuated vaccines.


Assuntos
Salmonelose Animal , Vacinas contra Salmonella , Animais , Humanos , Salmonella enteritidis , Vacinas contra Salmonella/genética , Virulência/genética , Proteínas de Bactérias , Células CACO-2 , Salmonelose Animal/microbiologia
7.
Nucleic Acids Res ; 50(5): 2973-2985, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35191490

RESUMO

Serine integrases are emerging as one of the most powerful biological tools for synthetic biology. They have been widely used across genome engineering and genetic circuit design. However, developing serine integrase-based tools for directly/precisely manipulating synthetic biobricks is still missing. Here, we report SYMBIOSIS, a versatile method that can robustly manipulate DNA parts in vivo and in vitro. First, we propose a 'keys match locks' model to demonstrate that three orthogonal serine integrases are able to irreversibly and stably switch on seven synthetic biobricks with high accuracy in vivo. Then, we demonstrate that purified integrases can facilitate the assembly of 'donor' and 'acceptor' plasmids in vitro to construct composite plasmids. Finally, we use SYMBIOSIS to assemble different chromoprotein genes and create novel colored Escherichia coli. We anticipate that our SYMBIOSIS strategy will accelerate synthetic biobrick manipulation, genetic circuit design and multiple plasmid assembly for synthetic biology with broad potential applications.


Assuntos
Integrases , Serina , Biologia Sintética/métodos , Escherichia coli/genética , Integrases/genética , Plasmídeos/genética , Serina/genética
8.
Artigo em Inglês | MEDLINE | ID: mdl-38814613

RESUMO

Objective: To explore how miRNA-28-3p targets BIN1 and affects the biological behavior of nasopharyngeal carcinoma cells, and to evaluate its potential as a predictive biomarker for NPC. Methods: We studied 100 nasopharyngeal carcinoma patients who underwent surgery between January 2021 and January 2022. Tissues from tumors and adjacent normal areas were analyzed. Participants were categorized into two groups: one with nasopharyngeal carcinoma and another with adjacent normal tissue. Additionally, the nasopharyngeal carcinoma cell line CNE-2 was divided into three groups: an untreated control, a negative control with NC plasmid, and a test group treated with a miRNA-28-3p inhibitor. Key techniques included PCR, Western blotting, CCK-8, flow cytometry, focusing on the interactions between miRNA-28-3p and BIN1 and their predictive significance for NPC. Results: miRNA-28-3p levels were significantly higher in nasopharyngeal carcinoma tissues compared to adjacent normal tissues (P < .05). The predictive performance of miRNA-28-3p for NPC featured an AUC > 0.75 with sensitivity and specificity both exceeding 70% (P < .001). In nasopharyngeal carcinoma cells, miRNA-28-3p levels were significantly elevated compared to normal cells (P < .05). Transfection with the miRNA-28-3p inhibitor increased apoptosis and BIN1 protein levels while reducing cell proliferation, invasion, and migration significantly (P < .05). Conclusion: miRNA-28-3p is overexpressed in nasopharyngeal carcinoma and inhibits tumor cell proliferation, migration, and invasion, while promoting apoptosis by targeting BIN1. The level of miRNA-28-3p expression serves as a sensitive indicator for predicting nasopharyngeal carcinoma, affirming its potential as a diagnostic biomarker and underscoring the significance of these findings in enhancing understanding and clinical management of NPC.

9.
Molecules ; 29(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38675637

RESUMO

The detection of volatile amines is necessary due to the serious toxicity hazards they pose to human skin, respiratory systems, and nervous systems. However, traditional amines detection methods require bulky equipment, high costs, and complex measurements. Herein, we report a new simple, rapid, convenient, and visual method for the detection of volatile amines based on the gas-solid reactions of tetrachloro-p-benzoquinone (TCBQ) and volatile amines. The gas-solid reactions of TCBQ with a variety of volatile amines showed a visually distinct color in a time-dependent manner. Moreover, TCBQ can be easily fabricated into simple and flexible rapid test strips for detecting and distinguishing n-propylamine from other volatile amines, including ethylamine, n-butyamine, n-pentamine, n-butyamine and dimethylamine, in less than 3 s without any equipment assistance.

10.
Angew Chem Int Ed Engl ; : e202406465, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705847

RESUMO

The surrounding hydrogen bond (H-bond) interaction around the active sites plays indispensable functions in enabling the organic electrode materials (OEMs) to fulfill their roles as ion reservoirs in aqueous zinc-organic batteries (ZOBs). Despite important, there are still no works could fully shed its real effects light on. Herein, quinone-based small molecules with a H-bond evolution model has been rationally selected to disclose the regulation and equilibration of H-bond interaction between OEMs, and OEM and the electrolyte. It has been found that only a suitable H-bond interaction could make the OEMs fully liberate their potential performance. Accordingly, the 2,5-diaminocyclohexa-2,5-diene-1,4-dione (DABQ) with elaborately designed H-bond structure exhibits a capacity of 193.3 mAh g-1 at a record-high mass loading of 66.2 mg cm-2 and 100 % capacity retention after 1500 cycles at 5 A g-1. In addition, the DABQ//Zn battery also possesses air-rechargeable ability by utilizing the chemistry redox of proton. Our results put forward a specific pathway to precise utilization of H-bond to liberate the performance of OEMs.

11.
Angew Chem Int Ed Engl ; 63(27): e202402497, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38679571

RESUMO

The large size of K-ion makes the pursuit of stable high-capacity anodes for K-ion batteries (KIBs) a formidable challenge, particularly for high temperature KIBs as the electrode instability becomes more aggravated with temperature climbing. Herein, we demonstrate that a hollow ZnS@C nanocomposite (h-ZnS@C) with a precise shell modulation can resist electrode disintegration to enable stable high-capacity potassium storage at room and high temperature. Based on a model electrode, we identify an interesting structure-function correlation of the h-ZnS@C: with an increase in the shell thickness, the cyclability increases while the rate and capacity decrease, shedding light on the design of high-performance h-ZnS@C anodes via engineering the shell thickness. Typically, the h-ZnS@C anode with a shell thickness of 60 nm can deliver an impressive comprehensive performance at room temperature; the h-ZnS@C with shell thickness increasing to 75 nm can achieve an extraordinary stability (88.6 % capacity retention over 450 cycles) with a high capacity (450 mAh g-1) and a superb rate even at an extreme temperature of 60 °C, which is much superior than those reported anodes. This contribution envisions new perspectives on rational design of functional metal sulfides composite toward high-performance KIBs with insights into the significant structure-function correlation.

12.
J Neuroinflammation ; 20(1): 247, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880726

RESUMO

BACKGROUND: The astrocytes in the central nervous system (CNS) exhibit morphological and functional diversity in brain region-specific pattern. Functional alterations of reactive astrocytes are commonly present in human temporal lobe epilepsy (TLE) cases, meanwhile the neuroinflammation mediated by reactive astrocytes may advance the development of hippocampal epilepsy in animal models. Nuclear factor I-A (NFIA) may regulate astrocyte diversity in the adult brain. However, whether NFIA endows the astrocytes with regional specificity to be involved in epileptogenesis remains elusive. METHODS: Here, we utilize an interference RNA targeting NFIA to explore the characteristics of NFIA expression and its role in astrocyte reactivity in a 4-aminopyridine (4-AP)-induced seizure model in vivo and in vitro. Combined with the employment of a HA-tagged plasmid overexpressing NFIA, we further investigate the precise mechanisms how NIFA facilitates epileptogenesis. RESULTS: 4-AP-induced NFIA upregulation in hippocampal region is astrocyte-specific, and primarily promotes detrimental actions of reactive astrocyte. In line with this phenomenon, both NFIA and vanilloid transient receptor potential 4 (TRPV4) are upregulated in hippocampal astrocytes in human samples from the TLE surgical patients and mouse samples with intraperitoneal 4-AP. NFIA directly regulates mouse astrocytic TRPV4 expression while the quantity and the functional activity of TRPV4 are required for 4-AP-induced astrocyte reactivity and release of proinflammatory cytokines in the charge of NFIA upregulation. NFIA deficiency efficiently inhibits 4-AP-induced TRPV4 upregulation, weakens astrocytic calcium activity and specific astrocyte reactivity, thereby mitigating aberrant neuronal discharges and neuronal damage, and suppressing epileptic seizure. CONCLUSIONS: Our results uncover the critical role of NFIA in astrocyte reactivity and illustrate how epileptogenic brain injury initiates cell-specific signaling pathway to dictate the astrocyte responses.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Fatores de Transcrição NFI , Canais de Cátion TRPV , Animais , Humanos , Camundongos , 4-Aminopiridina/efeitos adversos , Astrócitos/metabolismo , Encéfalo/metabolismo , Sistema Nervoso Central/metabolismo , Epilepsia/metabolismo , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/metabolismo , Fatores de Transcrição NFI/genética , Fatores de Transcrição NFI/metabolismo , Canais de Cátion TRPV/metabolismo , Regulação para Cima
13.
PLoS Pathog ; 17(6): e1009647, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34125864

RESUMO

HIV-1 functional cure requires sustained viral suppression without antiretroviral therapy. While effector-memory CD8+ T lymphocytes are essential for viremia control, few vaccines elicit such cellular immunity that could be potently recalled upon viral infection. Here, we investigated a program death-1 (PD1)-based vaccine by fusion of simian immunodeficiency virus capsid antigen to soluble PD1. Homologous vaccinations suppressed setpoint viremia to undetectable levels in vaccinated macaques following a high-dose intravenous challenge by the pathogenic SHIVSF162P3CN. Poly-functional effector-memory CD8+ T cells were not only induced after vaccination, but were also recalled upon viral challenge for viremia control as determined by CD8 depletion. Vaccine-induced effector memory CD8+ subsets displayed high cytotoxicity-related genes by single-cell analysis. Vaccinees with sustained viremia suppression for over two years responded to boost vaccination without viral rebound. These results demonstrated that PD1-based vaccine-induced effector-memory CD8+ T cells were recalled by AIDS virus infection, providing a potential immunotherapy for functional cure.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Receptor de Morte Celular Programada 1/imunologia , Vacinas contra a SAIDS/imunologia , Viremia/prevenção & controle , Animais , Feminino , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia , Vacinas de DNA/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia
14.
Cell Tissue Res ; 391(3): 577-594, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36527485

RESUMO

Preferentially expressed antigen in melanoma (PRAME) is a cancer/testis antigen (CTA) that is predominantly expressed in normal male gonad tissues and a variety of tumors. PRAME proteins are present in the acrosome and sperm tail, but their role in sperm function is unknown. The objective of this study was to examine the function of the bovine Y-linked PRAME (PRAMEY) during spermatozoal capacitation, the acrosome reaction (AR), and fertilization. Freshly ejaculated spermatozoa were induced to capacitate and undergo AR in vitro. Western blotting results revealed a decrease in the PRAMEY protein in capacitated spermatozoa, and the release of the PRAMEY protein from the acrosome during the AR, suggesting its involvement in sperm capacitation and AR. IVF was performed using in vitro matured bovine oocytes and cauda epididymal spermatozoa either treated with PRAMEY antibody, rabbit IgG, or DPBS. Sperm-egg binding and early embryos were examined at 6 and 45 h post IVF, respectively. The number of spermatozoa that bound per oocyte was nearly two-fold greater in the PRAMEY antibody treatment group (34.4) when compared to both the rabbit IgG (17.6) and DPBS (18.1) controls (P < 0.01). Polyspermy rate in the antibody-treated group (18.9%) was three-fold greater than the rabbit IgG control (6.0%) (P < 0.01). The results indicate that PRAMEY may play a role in anti-polyspermy defense. This study thus provides the initial evidence for the involvement of the PRAME protein family in sperm function and fertilization.


Assuntos
Sêmen , Espermatozoides , Coelhos , Masculino , Animais , Bovinos , Espermatozoides/metabolismo , Fertilização in vitro , Acrossomo , Capacitação Espermática , Imunoglobulina G , Fertilização
15.
Mol Phylogenet Evol ; 184: 107778, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37030415

RESUMO

Leaf-mining flies (Diptera: Agromyzidae) are a diverse clade of phytophagous Diptera known largely for their economic impact as leaf- or stem-miners on vegetable and ornamental plants. Higher-level phylogenetic relationships of Agromyzidae have remained uncertain because of challenges in sampling of both taxa and characters for morphology and PCR-based Sanger-era molecular systematics. Here, we used hundreds of orthologous single-copy nuclear loci obtained from anchored hybrid enrichment (AHE) to reconstruct phylogenetic relationships among the major lineages of leaf-mining flies. The resulting phylogenetic trees are highly congruent and well-supported, except for a few deep nodes, when using different molecular data types and phylogenetic methods. Based on divergence time dating using a relaxed clock model-based analysis, leaf-mining flies are shown to have diversified in multiple lineages since the early Paleocene, approximately 65 million years ago. Our study not only reveals a revised classification system of leaf-mining flies, but also provides a new phylogenetic framework to understand their macroevolution.


Assuntos
Dípteros , Filogenia , Genômica , Dípteros/genética , Animais , Funções Verossimilhança , Loci Gênicos
16.
Biotechnol Bioeng ; 120(3): 793-802, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36510694

RESUMO

Nonribosomal peptides (NRPs) are a large family of secondary metabolites with notable bioactivities, which distribute widely in natural resources across microbes and plants. To obtain these molecules, heterologous production of NRPs in robust surrogate hosts like Escherichia coli represent a feasible approach. However, reconstitution of the full biosynthetic pathway in a host often leads to low productivity, which is at least in part due to the low efficiency of enzyme interaction in vivo except for the well-known reasons of metabolic burden (e.g., expression of large NRP synthetases-NRPSs with molecular weights of >100 kDa) and cellular toxicity on host cells. To enhance the catalytic efficiency of large NRPSs in vivo, here we propose to staple NRPS enzymes by using short peptide/protein pairs (e.g., SpyTag/SpyCatcher) for enhanced NRP production. We achieve this goal by introducing a stapled NRPS system for the biosynthesis of the antibiotic NRP valinomycin in E. coli. The results indicate that stapled valinomycin synthetase (Vlm1 and Vlm2) enables higher product accumulation than those two free enzymes (e.g., the maximum improvement is nearly fourfold). After further optimization by strain and bioprocess engineering, the final valinomycin titer maximally reaches about 2800 µg/L, which is 73 times higher than the initial titer of 38 µg/L. We expect that stapling NRPS enzymes will be a promising catalytic strategy for high-level biosynthesis of NRP natural products.


Assuntos
Antibacterianos , Escherichia coli , Valinomicina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Vias Biossintéticas , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Peptídeos/metabolismo
17.
J Org Chem ; 88(20): 14619-14633, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37789599

RESUMO

Construction of pyrrolidinyl-spiroindoles with easily available starting materials has attracted considerable attention from the synthesis community and is in great demand. Here, we describe a base-promoted formal (3 + 2) cycloaddition of α-halohydroxamates with alkenyl-iminoindolines. The present methodology features mild reaction conditions and a broad substrate scope with up to 99% yield and excellent diastereoselectivity. The versatility of this approach is demonstrated through valuable synthetic transformations. Preliminary mechanistic studies shed light on the mechanism of this cycloaddition process.

18.
Rapid Commun Mass Spectrom ; 37(17): e9606, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37580506

RESUMO

RATIONALE: Zinc isotopes are becoming increasingly applicable in high-temperature geochemistry, for example in crust-mantle interaction and volatilization-related processes. The published zinc isotope data for some commonly used reference materials, however, show large interlaboratory offsets. In addition, there is still limited data for zinc isotope compositions of many widely used geological reference materials. METHODS: For precise and accurate zinc isotopic ratio analysis of chemically diverse geostandards, including ultramafic to felsic igneous rocks, carbonatites, sediments and soils, an improved procedure for chemical purification of zinc was introduced in this study. The factors potentially affecting zinc isotopic ratio measurement were assessed. The accuracy and long-term reproducibility were obtained by measurements on both synthetic solutions and well-characterized geostandards. RESULTS: Purification of geologic samples with different zinc concentrations and matrix compositions yields consistent elution curves with nearly 100% recovery. Acidity and concentration mismatches and the presence of some matrix elements (e.g., Mg, Ti and Cr) have significant impacts on the precision and accuracy of zinc isotopic ratio measurement. The zinc isotope compositions of a suite of reference materials were measured using this method. CONCLUSIONS: The present study describes methods for the chemical purification of zinc and high-precision and accurate zinc isotopic ratio measurements using multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS). The long-term external reproducibility for δ66 Zn values is ±0.04‰ (2SD). High-quality zinc isotope data of chemically different geostandards were reported to stimulate future interlaboratory calibrations.

19.
Epidemiol Infect ; 151: e174, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37675640

RESUMO

Rodents and shrews are major reservoirs of various pathogens that are related to zoonotic infectious diseases. The purpose of this study was to investigate co-infections of zoonotic pathogens in rodents and shrews trapped in four provinces of China. We sampled different rodent and shrew communities within and around human settlements in four provinces of China and characterised several important zoonotic viral, bacterial, and parasitic pathogens by PCR methods and phylogenetic analysis. A total of 864 rodents and shrews belonging to 24 and 13 species from RODENTIA and EULIPOTYPHLA orders were captured, respectively. For viral pathogens, two species of hantavirus (Hantaan orthohantavirus and Caobang orthohantavirus) were identified in 3.47% of rodents and shrews. The overall prevalence of Bartonella spp., Anaplasmataceae, Babesia spp., Leptospira spp., Spotted fever group Rickettsiae, Borrelia spp., and Coxiella burnetii were 31.25%, 8.91%, 4.17%, 3.94%, 3.59%, 3.47%, and 0.58%, respectively. Furthermore, the highest co-infection status of three pathogens was observed among Bartonella spp., Leptospira spp., and Anaplasmataceae with a co-infection rate of 0.46%. Our results suggested that species distribution and co-infections of zoonotic pathogens were prevalent in rodents and shrews, highlighting the necessity of active surveillance for zoonotic pathogens in wild mammals in wider regions.


Assuntos
Bartonella , Coinfecção , Leptospira , Animais , Bartonella/genética , China/epidemiologia , Filogenia , Roedores/microbiologia , Musaranhos/microbiologia
20.
Mol Biol Rep ; 50(2): 1885-1894, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36515825

RESUMO

Cellular Retinol Binding Protein 1 (CRBP1) gene is a protein coding gene located on human chromosome 3q21, which codifies a protein named CRBP1. CRBP1 is widely expressed in many tissues as a chaperone protein to regulate the uptake, subsequent esterification and bioavailability of retinol. CRBP1 combines retinol and retinaldehyde with high affinity to protect retinoids from non-specific oxidation, and transports retinoids to specific enzymes to promote the biosynthesis of retinoic acid. The vital role of CRBP1 in retinoids metabolism has been gradually discovered, which has been implicated in tumorigenesis. However, the precise functions of CRBP1 in different diseases are still poorly understood. The purpose of this review is to provide an overview of the role of CRBP1 in various diseases, especially in both the promotion and inhibition of cancers, which may also offer a novel biomarker and potential therapeutic target for human diseases.


Assuntos
Neoplasias , Vitamina A , Humanos , Proteínas Celulares de Ligação ao Retinol/genética , Proteínas Celulares de Ligação ao Retinol/metabolismo , Vitamina A/metabolismo , Biomarcadores Tumorais/genética , Retinoides/metabolismo , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/terapia , Tretinoína
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