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Background: Altitude illness has serious effects on individuals who are not adequately acclimatized to high-altitude areas and may even lead to death. However, the individualized mechanisms of onset and preventive measures are not fully elucidated at present, especially the relationship between altitude illness and elements, which requires further in-depth research. Methods: Fresh serum samples were collected from individuals who underwent health examinations at the two hospitals in Xining and Sanya between November 2021 and December 2021. The blood zinc (Zn), iron (Fe), and calcium (Ca) concentrations, as well as hypoxia-inducible factor 1-alpha (HIF-1α) concentrations, were measured. This study conducted effective sample size estimation, repeated experiments, and used GraphPad Prism 9.0 and IBM SPSS version 19.0 software for comparative analysis of differences in the expression of elements and HIF-1α among different ethnic groups, altitudes, and concentration groups. Linear regression and multiple linear regression were employed to explore the relationships among elements and their correlation with HIF-1α. Results: This study included a total of 400 participants. The results from the repeated measurements indicated that the consistency of the laboratory test results was satisfactory. In terms of altitude differences, except for Fe (p = 0.767), which did not show significant variance between low and high altitude regions, Zn, Ca, and HIF-1α elements all exhibited notable differences between these areas (p < 0.0001, p = 0.004, and p < 0.0001). When grouping by the concentrations of elements and HIF-1α, the results revealed significant variations in the distribution of zinc among different levels of iron and HIF-1α (p < 0.05). The outcomes of the linear regression analysis demonstrated that calcium and zinc, iron and HIF-1α, calcium and HIF-1α, and zinc and HIF-1α displayed substantial overall explanatory power across different subgroups (p < 0.05). Finally, the results of the multiple linear regression analysis indicated that within the high-altitude population, the Li ethnic group in Sanya, and the Han ethnic group in Sanya, the multiple linear regression model with HIF-1αas the dependent variable and elements as the independent variables exhibited noteworthy overall explanatory power (p < 0.05). Conclusion: The levels of typical elements and HIF-1α in the blood differ among various altitudes and ethnic groups, and these distinctions may be linked to the occurrence and progression of high-altitude illness.
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Laccase, a copper-containing polyphenol oxidase, is an important green biocatalyst. In this study, Laccase Lcc5 was homologous recombinantly expressed in Coprinopsis cinerea and a novel strategy of silencing chitinase gene expression was used to enhance recombinant Lcc5 extracellular yield. Two critical chitinase genes, ChiEn1 and ChiE2, were selected by analyzing the transcriptome data of C. cinerea FA2222, and their silent expression was performed by RNA interference (RNAi). It was found that silencing either ChiEn1 or ChiE2 reduced sporulation and growth rate, and increased cell wall sensitivity, but had no significant effect on mycelial branching. Among them, the extracellular laccase activity of the ChiE2-silenced engineered strain Cclcc5-antiChiE2-5 and the control Cclcc5-13 reached the highest values (38.2 and 25.5 U/mL, respectively) at 250 and 150 rpm agitation speeds, corresponding to productivity of 0.35 and 0.19 U/mL·h, respectively, in a 3-L fermenter culture. Moreover, since Cclcc5-antiChiE2-5 could withstand greater shear forces, its extracellular laccase activity was 2.6-fold higher than that of Cclcc5-13 when the agitation speed was all at 250 rpm. To our knowledge, this is the first report of enhanced recombinant laccase production in C. cinerea by silencing the chitinase gene. This study will pave the way for laccase industrial production and accelerate the development of a C. cinerea high-expression system. KEY POINTS: ⢠ChiEn1 and ChiE2 are critical chitinase genes in C. cinerea FA2222 genome. ⢠Chitinase gene silencing enhanced the tolerance of C. cinerea to shear forces. ⢠High homologous production of Lcc5 is achieved by fermentation in a 3-L fermenter.
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Quitinases , Inativação Gênica , Lacase , Quitinases/genética , Quitinases/metabolismo , Quitinases/biossíntese , Lacase/genética , Lacase/metabolismo , Lacase/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Agaricales/genética , Agaricales/enzimologia , Fermentação , Interferência de RNA , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Micélio/genética , Micélio/crescimento & desenvolvimento , Micélio/enzimologia , Parede Celular/metabolismo , Parede Celular/genéticaRESUMO
As the reliable biomarkers to evaluate the diabetes and neurological disease, sensitive and accurate detection of glucose and glutathione (GSH) in biological samples is necessary for early precaution and diagnosis of related-diseases. The single red upconversion nanoparticles (UCNPs) especially with core-shell structure can penetrate deeper biological tissues and cause less energy loss and thus have higher sensitivity and accuracy. Additionally, an enzyme-controlled cascade signal amplification (ECSAm) strategy will further enhance sensitivity. Herein, using single red UCNPs with core-shell structure as the luminescent material, a fluorescent sensor based on ECSAm was developed for the highly sensitive and accurate detection of glucose and GSH. Under the optimal conditions, the limits of detection for glucose and GSH by fluorescent method were 0.03 µM and 0.075 µM, separately. This assay was used to analyze the content of glucose and GSH in serum samples, and the obtained data was close to that of commercial blood glucose and GSH detection kit. The developed sensor platform based on single red UCNPs with core-shell structure and ECSAm can be a promising method for the accurate and sensitive detection of glucose and GSH in biological samples.
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Glucose , Nanopartículas , Luminescência , Nanopartículas/química , Glutationa/químicaRESUMO
Plasticizers are a type of toxic substance that may remain in food, posing significant health risks including carcinogenic, teratogenic, mutagenic, and other adverse effects. In this study, a novel strategy was employed by combining Pt@Au nanozymes with high catalytic properties to created two catalytic signal probes, designated as Pt@Au@Ab1 and Pt@Au@Ab2, specifically designed for the detection of dimethyl phthalate (DMP) and dibutyl phthalate (DBP). These catalytic signal probes served as the foundation for the development of a colorimetric immunoassay, enabling the simultaneous detection of both DMP and DBP. The colorimetric immunoassay is capable of detecting DMP in the range of 0.5-100 µg/L with a limit of detection as low as 0.1 µg/L and DBP in the range of 1-32 µg/L with a low limit of detection of 0.5 µg/L. The developed immunoassay can be used for the determination of the DMP and DBP in baijiu and plastic bottled drinks. The recovery rate is in the range of 96.4% and 100.5% and the coefficient of variation is between 1.0% and 7.2%. This innovative colorimetric immunoassay offers a robust tool for the simultaneous quantification of DMP and DBP in real samples.
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Dibutilftalato , Ácidos Ftálicos , Colorimetria , SmartphoneRESUMO
Despite the widespread use in industrial production, benzene derivatives are harmful to both human beings and the environment. The control of these substances has become an important subject of scientific research. This study introduces a new approach for adsorption and separation of benzene derivatives utilizing pagoda[n]arene based supramolecular materials. Density functional theory calculations were employed to investigate the molecular recognition mechanism of benzene derivatives by pagoda[4]arenes and pagoda[5]arenes (Pa[4]As and Pa[5]As). Results indicate that Pa[4]As and Pa[5]As can effectively accommodate benzene derivatives through non-covalent interactions, leading to the formation of stable host-guest complexes. Additionally, molecular dynamics simulations revealed that both crystalline and non-crystalline supramolecular aggregates of Pa[4]As and Pa[5]As possess the ability to adsorb benzene derivatives and maintain the stability of the adsorption. Moreover, increasing the temperature causes benzene derivatives to desorb from the adsorbing aggregates, and thus the material can be reutilized.
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BACKGROUND: To evaluate the efficacy and safety of acupuncture by systematically reviewing the literature on colorectal cancer resection. METHODS: Seven electronic databases were searched from inception to February 28, 2023. Randomized controlled trials on acupuncture in patients after CRC resection were included. Two reviewers independently selected relevant trials, extracted data, and assessed the risk of bias. A random-effects meta-analysis model was used to obtain summary effect estimates. The data were pooled and analyzed using RevMan 5.3. The heterogeneity of selected studies was evaluated by evaluating the I-squared (I2) statistics. RESULTS: Twenty-two studies with 1878 patients were included. Results of the meta-analysis showed there was a low level evidence that acupuncture may improve early postoperative symptoms, such as time to first flatus (n = 876, MD -0.77h, 95% CI -1.22 to -0.33 h, I2 = 89%), time to first bowel movement (n = 671, MD -1.41h, 95% CI -2.20 to -0.63 h, I2 = 95%), time to first defecation (n = 556, MD -1.03h, 95% CI -1.88 to -0.18 h, I2 = 95%), and nausea/vomiting (n = 1488, RR 0.72, 95% CI 0.59-0.89, I2 = 49%) compared with usual care and sham acupuncture. However, there were no statistically significant differences in postoperative pain (n = 1188, MD-0.21, 95% CI -0.59 to 0.17, I2 = 74%). And there was no sufficient evidence of improving long-term functional outcomes. There was substantial heterogeneity across trials. The adverse events associated with acupuncture stimulation were minor in include studies. CONCLUSION SUBSECTIONS: There is currently low-level evidence supporting the use of acupuncture on postoperative symptoms for patients after colorectal cancer resection. More investigations should be established based on the STRICTA statement strictly.
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Terapia por Acupuntura , Neoplasias Colorretais , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Dor Pós-Operatória , Bases de Dados Factuais , Neoplasias Colorretais/cirurgiaRESUMO
Saphenous vein bypass grafting is an effective technique used to treat peripheral arterial disease (PAD). However, restenosis is the major clinical challenge for the graft vessel among people with PAD postoperation. We hypothesize that there is a common culprit behind arterial occlusion and graft restenosis. To investigate this hypothesis, we found TGF-ß, a gene specifically upregulated in PAD arteries, by bioinformatics analysis. TGF-ß has a wide range of biological activities and plays an important role in vascular remodeling. We discuss the molecular pathway of TGF-ß and elucidate its mechanism in vascular remodeling and intimal hyperplasia, including EMT, extracellular matrix deposition, and fibrosis, which are the important pathways contributing to stenosis. Additionally, we present a case report of a patient with graft restenosis linked to the TGF-ß pathway. Finally, we discuss the potential applications of targeting the TGF-ß pathway in the clinic to improve the long-term patency of vein grafts.
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Doença Arterial Periférica , Túnica Íntima , Humanos , Túnica Íntima/metabolismo , Veia Safena/metabolismo , Remodelação Vascular , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Doença Arterial Periférica/cirurgia , Doença Arterial Periférica/metabolismoRESUMO
Many non-nucleoside human cytomegalovirus (HCMV) inhibitors have been reported in patent and scientific literature, however, none have reached commercialization despite the urgent need for new HCMV treatments. Herein we report select compounds from different templates that all had low micromolar human ether-à-go-go (hERG) ion channel IC50 values. We also describe a series of pyrroloquinoline derivatives that were designed and synthesized to understand the effect of various substitution on human cytomegalovirus (HCMV) polymerase activity, antiviral activity, and hERG inhibition. These results demonstrated that hERG inhibition can be significantly altered based on the substitution on this template. An HCMV inhibitor with low hERG inhibition and reduced cytotoxicity is also described. The results suggest substitution can be fine tuned for the non-nucleoside polymerase inhibitors to reduce hERG inhibition and maintain HCMV antiviral potency.
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Antivirais , Citomegalovirus , Humanos , Antivirais/farmacologia , Éter/farmacologia , Canais de Potássio Éter-A-Go-Go , Cardiotoxicidade , Etil-Éteres/farmacologia , Nucleotidiltransferases , Éteres/farmacologia , Canal de Potássio ERG1 , Bloqueadores dos Canais de Potássio/farmacologiaRESUMO
In this study, a novel poly (lactic-co-glycolic acid) (PLGA)-based micelle was synthesized, which could improve the therapeutic effect of the antitumor drug doxorubicin hydrochloride (DOX) and reduce its toxic and side effects. The efficient delivery of DOX was achieved by active targeting mediated by double receptors and stimulating the reduction potential in tumor cells. FA-HA-SS-PLGA polymer was synthesized by amidation reaction, and then DOX-loaded micelles were prepared by dialysis method. The corresponding surface method was used to optimize the experimental design. DOX/FA-HA-SS-PLGA micelles with high drug loading rate and encapsulation efficiency were prepared. The results of hydrophilic experiment, critical micelle concentration determination, and hemolysis test all showed that DOX/FA-HA-SS-PLGA micelles had good physicochemical properties and biocompatibility. In addition, both in vitro reduction stimulus response experiment and in vitro release experiment showed that DOX/FA-HA-SS-PLGA micelles had reduction sensitivity. Molecular docking experiments showed that it can bind to the target protein. More importantly, in vitro cytology studies, human breast cancer cells (MCF-7), human non-small cell lung cancer cells (A549), and mouse colon cancer cells (CT26) were used to demonstrate that the dual receptor-mediated endocytosis pathway resulted in stronger cytotoxicity to tumor cells and more significant apoptosis. In and in vivo antitumor experiment, tumor-bearing nude mice were used to further confirm that the micelles with double targeting ligands had better antitumor effect and lower toxicity. These experimental results showed that DOX/FA-HA-SS-PLGA micelles have the potential to be used as chemotherapeutic drugs for precise tumor treatment.
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BACKGROUND: Emerging studies support the oncogenic role of WD repeat domain 62 (WDR62) in few tumors, while no pan-cancer analysis is available. In this study, we analyzed systematically the oncogenic role of WDR62 across a series of human tumors based on bioinformatic data mining. METHODS: The expression level of WDR62 was analyzed via GEPIA2, TIMER, UALCAN, and StarBase databases. The prognostic role was analyzed via GEPIA2, TIMER, UALCAN, StarBase, TISIDB, TCGA portal, Kaplan-Meier Plotter, and PrognoScan databases. Then, we explored the causes for WDR62 abnormal expression via TCGA portal and UALCAN databases. Subsequently, the STRING and GeneMANIA databases were used to find the interactive networks for WDR62. Furthermore, we analyzed the correlation between WDR62 expression and immune features via TIMER and TISIDB databases. RESULTS: We found that WDR62 was significantly upregulated in most of the tumors and correlated with poor prognosis mainly in 6 candidate tumors-BLCA, BRCA, KIRC, KIRP, LIHC, and LUAD. Abnormal WDR62 expression may be probably attributed to TP53 mutation and promoter DNA methylation. Relative network analysis demonstrated that WDR62 was mainly involved in MAPK and toll-like receptor signaling pathway. WDR62 expression was associated with various immune cell infiltrations, especially cancer-associated fibroblasts (CAF) and T cell regulatory (Treg) cells, and was markedly correlated with poor prognosis. Moreover, WDR62 expression was closely associated with the expression of some immunomodulators such as PD-L1 and has a significant prognostic value. CONCLUSIONS: Our study revealed that WDR62 could serve as a diagnostic and prognostic biomarker for several cancers. Importantly, WDR62 was closely associated with various immune cell infiltration, and to a certain extent, it can predict the effect of immunotherapy in particular PD1/PD-L1 inhibitors. Our pan-cancer study provided useful information on the oncogenic role of WDR62, contributing to further exploring the underlying mechanisms.
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Proteínas de Ciclo Celular/fisiologia , Neoplasias/fisiopatologia , Proteínas do Tecido Nervoso/fisiologia , Oncogenes , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias/genéticaRESUMO
Targeting delivery is a promising technique for the therapy of cancers. A molecule FA-EEYSV-NH2, which consists of target recognition site folic acid (FA), dipeptide linker, and peptide drug, was designed as a novel anticancer prodrug. The molecules could self-assemble into nanoparticles at pH 7.0 and nanofibers at pH 5.0. By the aid of pH-responsiveness, the self-assemblies were used purposefully as targeted vehicles of self-delivery prodrugs. The results of cell toxicity and internalization assays have proved that the self-assemblies have good cancer cell selectivity. The selection was mainly attributed to the pH-responsive structure transition of self-assemblies and the FA active-targeting effect. We hope that our work could provide a useful strategy for finely tuning the properties and activities of peptide-based supramolecular nanomaterials, thus optimizing nanomedicines with enhanced performance.
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Nanopartículas , Pró-Fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Ácido Fólico , Concentração de Íons de Hidrogênio , PeptídeosRESUMO
Mitophagy regulates the metabolic level and cell fates by specifically degrading damaged or redundant mitochondria in these cells. During the formation of autophagosomes, autophagy receptors and adaptors, which usually contain a LC3-interacting region (LIR) domain, are recruited through their interactions with LC3/GABARAP family of proteins. Bcl-rambo is one of the mitophagy receptors that interact with LC3s/GABARAPs. In this study, we first measured the binding of Bcl-rambo to LC3s/GABARAPs in vitro and found Bcl-rambo has a selectivity to LC3C/GABARP/GABARAPL1. Further investigations with bioinformatics analyses and mutagenesis suggested that the interactions with the HP1 and HP2 sites of LC3s/GABARAPs and the residues at the X2 site of the LIR domain of Bcl-rambo are both critical for the selectivity. Moreover, assays in vivo showed that manipulating the selective binding of Bcl-rambo resulted in the changes of mitophagy inductions in the cells. Overall, our data revealed the selective binding between Bcl-rambo and LC3s/GABARAPs and its molecular mechanisms and biological significances, which will be helpful for future studies of mitophagy mediated by Bcl-rambo.
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Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Mitofagia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Reguladoras de Apoptose/química , Sítios de Ligação , Células HEK293 , Humanos , Proteínas Associadas aos Microtúbulos/química , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Mapas de Interação de Proteínas , Proteínas Proto-Oncogênicas c-bcl-2/químicaRESUMO
BACKGROUND: Pelvic organ prolapse (POP) is the downward descent of vaginal walls, affecting the health of 32% to 76% female patients. Conservative interventions are considered as priority before seeking help from surgery. We plan to make the systematic review to assess the effectiveness of conservative intervention for adult women with POP. METHODS: Studies will be searched in PubMed, EMBASE, and the Cochrane Library from inception to July 2017. Primary outcomes are specific POP-related symptom, severity of prolapse, Prolapse-related, and general health-related quality of life and other non-POP-specific symptoms. RESULTS: The data will be synthesized if possible using MD, SMD or RR. A descriptive analysis will be made if the data cannot be synthesized. DISCUSSION: The systematic review might provide solid evidence for the treatment of POP by conservative intervention.
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Tratamento Conservador , Prolapso de Órgão Pélvico/terapia , Revisões Sistemáticas como Assunto , Adulto , Feminino , Humanos , Projetos de PesquisaRESUMO
The coassembly behavior of peptide amphiphiles (PAs) C4-Bhc-EE-NH2 and C14-FKK-NH2 has been investigated by transmission electron microscopy, atomic force microscopy, fluorescence microscopy, circular dichroism, Fourier transform infrared spectroscopy, and 1H nuclear magnetic resonance. These two PAs coassembled into nanofibers by electrostatic and π-π stacking interactions at a low concentration and further aggregated into nanofiber bundles via charge complementation on the surface of nanofibers. As the charge number varied with pH, the bundles could be disassembled/assembled with pH regulation. More interestingly, as C4-Bhc-EE-NH2 was a photodegradable molecule, the bundles could also be responsive to both ultraviolet (UV) and near-infrared (NIR) light. In contrast to the reversible pH-dependent response, the light responses were irreversible as C4-Bhc-EE-NH2 broke under UV or NIR radiation. The highlight of this article is that structural changes were realized for control at the aggregate level, not only at the molecular level. With this inspiration, we hope that we can support the novel biomaterial construction and exploitation of new functions of biomaterials.
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Interações Hidrofóbicas e Hidrofílicas , Luz , Peptídeos/química , Concentração de Íons de HidrogênioRESUMO
Molecular modification and self-assembly are clinically proved successful strategies in drug design to enhance the treatment efficiency. Herein, the lipidation method is used to modify the anticancer tripeptides tyoservaltide (YSV) into lipidated YSV, C16-EEYSV-NH2, and C16-KKYSV-NH2. We found the lipidated YSV performed better aggregation property from the critical aggregation concentration (CAC) measurements, transmission electron microscope (TEM) and atomic force microscope (AFM) observation. The cytotoxicity experiments showed that the lipidated YSV had better anticancer efficiency due to their excellent self-assembly. Meantime, the lipidated YSV shows superior biostability and cells internalization which can be proved by high performance liquid chromatography (HPLC), inverted fluorescence microscope, and flow cytometry (FCM). For in vivo experiments, the results also showed that lipidated YSV have better performance, and the final histology analysis shows low toxicity to the body organs. Considering the advantages of lipidated YSV, we hope that our study would demonstrate a powerful strategy to improve the application of peptide drugs.
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Trypanosoma brucei (T. brucei) is a parasitic protozoan causing human sleeping sickness and related animal diseases. ENT (EMSY N-terminal) domain was first found in EMSY protein which has been proved to be involved in multiple biological processes such as DNA repair, tumorigenesis, and transcriptional regulation. So far, little is known about the function and structure of ENT domains from protozoan. Q385P5 from T. brucei, containing an ENT domain at its N-terminus, is a conserved protein in related kinetoplastid parasites. In this work, the crystal structure of ENT domain of Q385P5 (TbENT) was solved at a resolution of 2.3â¯Å. TbENT adopts a club-like shape consisting of five helixes, which is similar to the structure of human EMSY ENT domain (HsENT). Interestingly, TbENT shows significantly different orientation on the fifth α-helix compared with HsENT. Meanwhile, human HP1 interacts with a conserved motif adjacent to EMSY ENT domain. However, this conserved binding motif is absent in Q385P5. These differences may imply the different protein interactions and roles of Q385P5 and its ENT domain in T. brucei.
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Domínios Proteicos , Estrutura Secundária de Proteína , Proteínas de Protozoários/química , Trypanosoma brucei brucei/metabolismo , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação/genética , Cristalografia por Raios X , Humanos , Modelos Moleculares , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Homologia de Sequência de Aminoácidos , Trypanosoma brucei brucei/genéticaRESUMO
Ubiquitin-like proteins play important roles in diverse biological processes. In Mycobacterium tuberculosis, Pup (prokaryotic ubiquitin-like protein), a functional homologue of eukaryotic ubiquitin, interacts with the proteasome ATPase subunit Mpa to recognize and unfold substrates, and then translocate them into the proteasome core for degradation. Previous studies revealed that, Pup, an intrinsically disordered protein (IDP), adopts a helical structure upon binding to the N-terminal coiled-coil domain of Mpa, at its disordered C-terminal region. In the present study, using circular dichroism (CD), surface plasmon resonance (SPR) and nuclear magnetic resonance (NMR), we show that membrane mimetic and acidic conditions also induce Pup to adopt helical conformations. Moreover, at low pH, Pup, via both of its N- and C-terminal regions, binds to Mpa on sites from the N-terminal region in addition to the C-terminal region of the coiled-coil domain. Our results imply Pup may play undiscovered roles in some biological processes e.g. those involve in membrane.
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Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Mycobacterium tuberculosis/metabolismo , Ubiquitinas/química , Ubiquitinas/metabolismo , Ácidos/química , Sítios de Ligação , Dicroísmo Circular , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Micelas , Modelos Moleculares , Mycobacterium tuberculosis/química , Ligação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Dodecilsulfato de Sódio/química , Ressonância de Plasmônio de SuperfícieRESUMO
Small ubiquitin-like modifier (SUMO), a reversible post-translational protein modifier, plays important roles in diverse cellular mechanisms. Three enzymes, E1 (activating enzyme), E2 (conjugating enzyme) and E3 (ligase), are involved in SUMO modification. SUMOylation system and process in higher eukaryotes have been well studied. However, in protozoa, such as Trypanosoma brucei (T. brucei), these remain poorly understood. Herein, we identified the E1 (TbAos1/TbUba2) and E2 (TbUbc9) enzymes of SUMOylation pathway in T. brucei by sequence analysis and GST pull-down assay. Furthermore, we successfully reconstructed the SUMOylation system in vitro with recombinant enzymes. Using this system, the active site of TbUba2 and TbUbc9 was revealed to be located at Cys343 and Cys132, respectively, and a centrin homologue (TbCentrin3) was identified to be a target of SUMOylation in T. brucei. Altogether, our results demonstrate that TbAos1/TbUba2 and TbUbc9 are the bona fide E1 and E2 enzymes of the SUMOylation system in T. brucei.
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Proteínas de Protozoários/metabolismo , Sumoilação , Trypanosoma brucei brucei/enzimologia , Trifosfato de Adenosina/farmacologia , Domínio Catalítico , Cisteína/metabolismo , Eletroforese em Gel de Poliacrilamida , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas de Protozoários/química , Homologia de Sequência de Aminoácidos , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/química , Enzimas de Conjugação de Ubiquitina/metabolismoRESUMO
Gastric cancer is one of the most common forms of malignant tumor, and the development of antigastric cancer drugs with minimal toxicity is of clinical importance. Allicin is extracted from Allium sativum (garlic). Recent research, including clinical experiments, has shown that garlic has anticancer and tumor suppressive effects. The present study aimed to investigate the effects of allicin on the MGC803 human gastric carcinoma cell line, and to further explore the possible mechanisms of its tumor suppressor effects. The effects of allicin on the MGC803 cells were initially examined using an 3(4,5dimethylthiazol2yl)2,5diphenyltetrazolium bromide assay. Hoechst staining was also used, in order to demonstrate the impact of allicin on MGC803 cell apoptosis. In addition, western blot analysis was performed to determine the abnormal expression levels of apoptosisassociated proteins, following the treatment of MGC803 cells with allicin. Western blotting was also used to investigate the specific mechanisms underlying allicininduced apoptosis of MGC803 cells. The rate of MGC803 apoptosis was significantly increased, when the concentration and treatment time of allicin were increased. Hoechst staining detected an enhanced rate of apoptosis, and enhanced expression levels of cleaved caspase 3 were determined by western blotting. Notably, the protein expression levels of p38 were increased when the MGC803 cells were treated with allicin. The results of the present study suggest that allicin may inhibit the proliferation and induce the apoptosis of MGC803 human gastric carcinoma cells, and this may partially be achieved through the enhanced expression of p38 and cleaved caspase 3.