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1.
PLoS Biol ; 21(1): e3001693, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36689548

RESUMEN

RNA recombination in positive-strand RNA viruses is a molecular-genetic process, which permits the greatest evolution of the genome and may be essential to stabilizing the genome from the deleterious consequences of accumulated mutations. Enteroviruses represent a useful system to elucidate the details of this process. On the biochemical level, it is known that RNA recombination is catalyzed by the viral RNA-dependent RNA polymerase using a template-switching mechanism. For this mechanism to function in cells, the recombining genomes must be located in the same subcellular compartment. How a viral genome is trafficked to the site of genome replication and recombination, which is membrane associated and isolated from the cytoplasm, is not known. We hypothesized that genome translation was essential for colocalization of genomes for recombination. We show that complete inactivation of internal ribosome entry site (IRES)-mediated translation of a donor enteroviral genome enhanced recombination instead of impairing it. Recombination did not occur by a nonreplicative mechanism. Rather, sufficient translation of the nonstructural region of the genome occurred to support subsequent steps required for recombination. The noncanonical translation initiation factors, eIF2A and eIF2D, were required for IRES-independent translation. Our results support an eIF2A/eIF2D-dependent mechanism under conditions in which the eIF2-dependent mechanism is inactive. Detection of an IRES-independent mechanism for translation of the enterovirus genome provides an explanation for a variety of debated observations, including nonreplicative recombination and persistence of enteroviral RNA lacking an IRES. The existence of an eIF2A/eIF2D-dependent mechanism in enteroviruses predicts the existence of similar mechanisms in other viruses.


Asunto(s)
Infecciones por Enterovirus , Enterovirus , Humanos , Enterovirus/fisiología , Infecciones por Enterovirus/virología , Sitios Internos de Entrada al Ribosoma , Factores de Iniciación de Péptidos/genética , Biosíntesis de Proteínas , ARN Viral/genética , ARN Viral/metabolismo , Interacciones Huésped-Patógeno
2.
Proc Natl Acad Sci U S A ; 119(28): e2204511119, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35867748

RESUMEN

Despite excellent vaccines, resurgent outbreaks of hepatitis A have caused thousands of hospitalizations and hundreds of deaths within the United States in recent years. There is no effective antiviral therapy for hepatitis A, and many aspects of the hepatitis A virus (HAV) replication cycle remain to be elucidated. Replication requires the zinc finger protein ZCCHC14 and noncanonical TENT4 poly(A) polymerases with which it associates, but the underlying mechanism is unknown. Here, we show that ZCCHC14 and TENT4A/B are required for viral RNA synthesis following translation of the viral genome in infected cells. Cross-linking immunoprecipitation sequencing (CLIP-seq) experiments revealed that ZCCHC14 binds a small stem-loop in the HAV 5' untranslated RNA possessing a Smaug recognition-like pentaloop to which it recruits TENT4. TENT4 polymerases lengthen and stabilize the 3' poly(A) tails of some cellular and viral mRNAs, but the chemical inhibition of TENT4A/B with the dihydroquinolizinone RG7834 had no impact on the length of the HAV 3' poly(A) tail, stability of HAV RNA, or cap-independent translation of the viral genome. By contrast, RG7834 inhibited the incorporation of 5-ethynyl uridine into nascent HAV RNA, indicating that TENT4A/B function in viral RNA synthesis. Consistent with potent in vitro antiviral activity against HAV (IC50 6.11 nM), orally administered RG7834 completely blocked HAV infection in Ifnar1-/- mice, and sharply reduced serum alanine aminotransferase activities, hepatocyte apoptosis, and intrahepatic inflammatory cell infiltrates in mice with acute hepatitis A. These results reveal requirements for ZCCHC14-TENT4A/B in hepatovirus RNA synthesis, and suggest that TENT4A/B inhibitors may be useful for preventing or treating hepatitis A in humans.


Asunto(s)
Proteínas Cromosómicas no Histona , ADN Polimerasa Dirigida por ADN , Virus de la Hepatitis A , Hepatitis A , Proteínas Intrínsecamente Desordenadas , ARN Nucleotidiltransferasas , ARN Viral , Replicación Viral , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , Proteínas Cromosómicas no Histona/metabolismo , ADN Polimerasa Dirigida por ADN/metabolismo , Hepatitis A/tratamiento farmacológico , Hepatitis A/metabolismo , Hepatitis A/virología , Virus de la Hepatitis A/efectos de los fármacos , Virus de la Hepatitis A/genética , Virus de la Hepatitis A/fisiología , Humanos , Proteínas Intrínsecamente Desordenadas/metabolismo , Ratones , Ratones Mutantes , ARN Nucleotidiltransferasas/metabolismo , ARN Viral/biosíntesis , ARN Viral/genética , Receptor de Interferón alfa y beta/genética , Replicación Viral/efectos de los fármacos
3.
J Biol Chem ; 299(12): 105443, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37949221

RESUMEN

The methyltransferase Trm10 modifies a subset of tRNAs on the base N1 position of the ninth nucleotide in the tRNA core. Trm10 is conserved throughout Eukarya and Archaea, and mutations in the human gene (TRMT10A) have been linked to neurological disorders such as microcephaly and intellectual disability, as well as defects in glucose metabolism. Of the 26 tRNAs in yeast with guanosine at position 9, only 13 are substrates for Trm10. However, no common sequence or other posttranscriptional modifications have been identified among these substrates, suggesting the presence of some other tRNA feature(s) that allow Trm10 to distinguish substrate from nonsubstrate tRNAs. Here, we show that substrate recognition by Saccharomyces cerevisiae Trm10 is dependent on both intrinsic tRNA flexibility and the ability of the enzyme to induce specific tRNA conformational changes upon binding. Using the sensitive RNA structure-probing method SHAPE, conformational changes upon binding to Trm10 in tRNA substrates, but not nonsubstrates, were identified and mapped onto a model of Trm10-bound tRNA. These changes may play an important role in substrate recognition by allowing Trm10 to gain access to the target nucleotide. Our results highlight a novel mechanism of substrate recognition by a conserved tRNA modifying enzyme. Further, these studies reveal a strategy for substrate recognition that may be broadly employed by tRNA-modifying enzymes which must distinguish between structurally similar tRNA species.


Asunto(s)
Conformación de Ácido Nucleico , Nucleótidos , ARN de Transferencia , Saccharomyces cerevisiae , ARNt Metiltransferasas , Humanos , Nucleótidos/metabolismo , ARN de Transferencia/química , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Especificidad por Sustrato , ARNt Metiltransferasas/química , ARNt Metiltransferasas/metabolismo
4.
Langmuir ; 39(38): 13695-13704, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37708347

RESUMEN

Amphiphilic Janus particles typically comprise two distinct hemispheres with spatially dispersed physicochemical properties. The anisotropic structure and physicochemical properties of Janus particles can be exploited for various applications. However, their preparation typically requires complex and sophisticated processes and expensive equipment to control the formation of different structures and chemical compositions. Herein, a simple synthetic approach for the facile fabrication of versatile Janus particles with efficient control of the Janus ratio and wettability based on particle fixation at a three-phase interface and photopolymerization is reported. Agarose gel and surfactant are used to control the surface-coated boundaries of the Janus particles through the equilibrium of a floating microparticle at the fluid interface. poly(propylene glycol) diacrylate or poly(N-isopropylacrylamide) coating on polystyrene-based microparticles allows easy control of the chemical functionality of the particle surfaces. Depending on the particle morphology and wettability, the interfacial behavior between two immiscible liquids can be adjusted, which allows the stabilization of Pickering emulsions that encapsulate independent oil droplets in water or vice versa. This facile approach has the potential to enable more efficient mass production of Janus particles and their use in various applications, such as biomedical and environmental engineering.

5.
Int J Mol Sci ; 23(4)2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35216078

RESUMEN

Metastasising cells express the intermediate filament protein vimentin, which is used to diagnose invasive tumours in the clinic. We aimed to clarify how vimentin regulates the motility of metastasising fibroblasts. STED super-resolution microscopy, live-cell imaging and quantitative proteomics revealed that oncogene-expressing and metastasising fibroblasts show a less-elongated cell shape, reduced cell spreading, increased cell migration speed, reduced directionality, and stronger coupling between these migration parameters compared to normal control cells. In total, we identified and compared 555 proteins in the vimentin interactome. In metastasising cells, the levels of keratin 18 and Rab5C were increased, while those of actin and collagen were decreased. Inhibition of HDAC6 reversed the shape, spreading and migration phenotypes of metastasising cells back to normal. Inhibition of HDAC6 also decreased the levels of talin 1, tropomyosin, Rab GDI ß, collagen and emilin 1 in the vimentin interactome, and partially reversed the nanoscale vimentin organisation in oncogene-expressing cells. These findings describe the changes in the vimentin interactome and nanoscale distribution that accompany the defective cell shape, spreading and migration of metastasising cells. These results support the hypothesis that oncogenes can act through HDAC6 to regulate the vimentin binding of the cytoskeletal and cell-extracellular matrix adhesion components that contribute to the defective motility of metastasising cells.


Asunto(s)
Movimiento Celular/fisiología , Fibroblastos/metabolismo , Fibroblastos/patología , Vimentina/metabolismo , Actinas/metabolismo , Animales , Adhesión Celular/fisiología , Forma de la Célula/fisiología , Uniones Célula-Matriz/metabolismo , Células Cultivadas , Colágeno/metabolismo , Citoesqueleto/metabolismo , Histona Desacetilasa 6/metabolismo , Humanos , Ratones , Oncogenes/fisiología
6.
J Neuroinflammation ; 17(1): 48, 2020 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-32019570

RESUMEN

BACKGROUND: Ischemic stroke is a main cause of mortality. Blood-brain barrier (BBB) breakdown appears to play a critical role in inflammation in patients with ischemic stroke and acceleration of brain injury. The BBB has a protective function and is composed of endothelial cells, pericytes, and astrocytes. In ischemic stroke treatments, regulation of vascular endothelial growth factor (VEGF)-A and vascular endothelial growth factor receptor (VEGFR)-2 is a crucial target despite adverse effects. Our previous study found that loss of C-type lectin family 14 member A (CLEC14A) activated VEGF-A/VEGFR-2 signaling in developmental and tumoral angiogenesis. Here, we evaluate the effects of BBB impairment caused by CLEC14A deficiency in ischemia-reperfusion injury. METHODS: In vitro fluorescein isothiocyanate (FITC)-dextran permeability, transendothelial electrical resistance (TEER) assay, and immunostaining were used to evaluate endothelial integrity. BBB permeability was assessed using Evans blue dye and FITC-dextran injection in Clec14a-/- (CLEC14A-KO) mice and wild-type mice. Middle cerebral artery occlusion surgery and behavioral assessments were performed to evaluate the neurologic damage. The change of tight junctional proteins, adhesion molecules, pro-inflammatory cytokines, and microglial were confirmed by immunofluorescence staining, Western blotting, and quantitative reverse transcription polymerase chain reaction of brain samples. RESULTS: In endothelial cells, knockdown of CLEC14A increased FITC-dextran permeability and decreased transendothelial electrical resistance; the severity of this effect increased with VEGF treatment. Immunofluorescence staining revealed that tight junctional proteins were attenuated in the CLEC14A knockdown endothelial cells. Consistent with the in vitro results, CLEC14A-KO mice that were injected with Evans blue dye had cerebral vascular leakage at postnatal day 8; wild-type mice had no leakage. We used a middle cerebral artery occlusion model and found that CLEC14A-KO mice had severe infarcted brain and neurological deficits with upregulated VEGFR-2 expression. FITC-dextran leakage was present in CLEC14A-KO mice after ischemia-reperfusion, and the numbers of tight junctional molecules were significantly decreased. Loss of CLEC14A increased the pro-inflammatory response through adhesion molecule expression, and glial cells were activated. CONCLUSIONS: These results suggest that activation of VEGFR-2 in CLEC14A-KO mice aggravates ischemic stroke by exacerbating cerebral vascular leakage and increasing neuronal inflammation after ischemia-reperfusion injury.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Lectinas Tipo C/metabolismo , Proteínas de la Membrana/metabolismo , Neuronas/metabolismo , Daño por Reperfusión/metabolismo , Animales , Barrera Hematoencefálica/patología , Encéfalo/metabolismo , Encéfalo/patología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Infarto de la Arteria Cerebral Media/genética , Infarto de la Arteria Cerebral Media/patología , Inflamación/metabolismo , Inflamación/patología , Lectinas Tipo C/genética , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Neuronas/patología , Permeabilidad , Daño por Reperfusión/genética , Daño por Reperfusión/patología
7.
Nature ; 515(7526): 279-282, 2014 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-25119035

RESUMEN

The mechanisms by which physical forces regulate endothelial cells to determine the complexities of vascular structure and function are enigmatic. Studies of sensory neurons have suggested Piezo proteins as subunits of Ca(2+)-permeable non-selective cationic channels for detection of noxious mechanical impact. Here we show Piezo1 (Fam38a) channels as sensors of frictional force (shear stress) and determinants of vascular structure in both development and adult physiology. Global or endothelial-specific disruption of mouse Piezo1 profoundly disturbed the developing vasculature and was embryonic lethal within days of the heart beating. Haploinsufficiency was not lethal but endothelial abnormality was detected in mature vessels. The importance of Piezo1 channels as sensors of blood flow was shown by Piezo1 dependence of shear-stress-evoked ionic current and calcium influx in endothelial cells and the ability of exogenous Piezo1 to confer sensitivity to shear stress on otherwise resistant cells. Downstream of this calcium influx there was protease activation and spatial reorganization of endothelial cells to the polarity of the applied force. The data suggest that Piezo1 channels function as pivotal integrators in vascular biology.


Asunto(s)
Células Endoteliales/citología , Células Endoteliales/fisiología , Fricción , Canales Iónicos/metabolismo , Estrés Mecánico , Animales , Embrión de Mamíferos/irrigación sanguínea , Embrión de Mamíferos/metabolismo , Femenino , Hemorreología , Masculino , Ratones
8.
Environ Microbiol ; 21(3): 1151-1169, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30773773

RESUMEN

Because molecular oxygen functions as the final acceptor of electrons during aerobic respiration and a substrate for diverse enzymatic reactions, eukaryotes employ various mechanisms to maintain cellular homeostasis under varying oxygen concentration. Human fungal pathogens change the expression of genes involved in virulence and oxygen-required metabolisms such as ergosterol (ERG) synthesis when they encounter oxygen limitation (hypoxia) during infection. The oxygen level in plant tissues also fluctuates, potentially creating hypoxic stress to pathogens during infection. However, little is known about how in planta oxygen dynamics impact pathogenesis. In this study, we investigated oxygen dynamics in rice during infection by Magnaporthe oryzae via two approaches. First, rice leaves infected by M. oryzae were noninvasively probed using a microscopic oxygen sensor. Second, an immunofluorescence assay based on a chemical probe, pimonidazole, was used. Both methods showed that oxygen concentration in rice decreased after fungal penetration. We also functionally characterized five hypoxia-responsive genes participating in ERG biosynthesis for their role in pathogenesis. Resulting insights and tools will help study the nature of in planta oxygen dynamics in other pathosystems.


Asunto(s)
Magnaporthe/fisiología , Oryza/microbiología , Oxígeno/metabolismo , Enfermedades de las Plantas/microbiología , Microambiente Celular , Proteínas Fúngicas/genética , Magnaporthe/genética , Oryza/metabolismo , Hojas de la Planta/microbiología , Virulencia
9.
Physiol Plant ; 165(3): 464-475, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30159898

RESUMEN

Plants exhibit helical growth movements known as circumnutation in growing organs. Some studies indicate that circumnutation involves the gravitropic response, but this notion is a matter of debate. Here, using the agravitropic rice mutant lazy1 and space-grown rice seedlings, we found that circumnutation was reduced or lost during agravitropic growth in coleoptiles. Coleoptiles of wild-type rice exhibited circumnutation in the dark, with vigorous oscillatory movements during their growth. The gravitropic responses in lazy1 coleoptiles differed depending on the growth stage, with gravitropic responses detected during early growth and agravitropism during later growth. The nutation-like movements observed in lazy1 coleoptiles at the early stage of growth were no longer detected with the disappearance of the gravitropic response. To verify the relationship between circumnutation and gravitropic responses in rice coleoptiles, we conducted spaceflight experiments in plants under microgravity conditions on the International Space Station. Wild-type rice seeds were germinated, and the resulting seedlings were grown under microgravity or a centrifuge-generated 1 g environment in space. We began filming the seedlings 2 days after seed imbibition and obtained images of seedling growth every 15 min. The seed germination rate in space was 92-100% under both microgravity and 1 g conditions. LED-synchronized flashlight photography induced an attenuation of coleoptile growth and circumnutational movement due to cumulative light exposure. Nevertheless, wild-type rice coleoptiles still showed circumnutational oscillations under 1 g but not microgravity conditions. These results support the idea that the gravitropic response is involved in plant circumnutation.


Asunto(s)
Cotiledón/fisiología , Oryza/fisiología , Plantones/fisiología , Cotiledón/genética , Gravitropismo/genética , Gravitropismo/fisiología , Mutación/genética , Oryza/genética , Plantones/genética
10.
Circ Res ; 119(3): 450-62, 2016 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-27245171

RESUMEN

RATIONALE: Blood flow-induced shear stress controls endothelial cell (EC) physiology during atherosclerosis via transcriptional mechanisms that are incompletely understood. The mechanosensitive transcription factor TWIST is expressed during embryogenesis, but its role in EC responses to shear stress and focal atherosclerosis is unknown. OBJECTIVE: To investigate whether TWIST regulates endothelial responses to shear stress during vascular dysfunction and atherosclerosis and compare TWIST function in vascular development and disease. METHODS AND RESULTS: The expression and function of TWIST1 was studied in EC in both developing vasculature and during the initiation of atherosclerosis. In zebrafish, twist was expressed in early embryonic vasculature where it promoted angiogenesis by inducing EC proliferation and migration. In adult porcine and murine arteries, TWIST1 was expressed preferentially at low shear stress regions as evidenced by quantitative polymerase chain reaction and en face staining. Moreover, studies of experimental murine carotid arteries and cultured EC revealed that TWIST1 was induced by low shear stress via a GATA4-dependent transcriptional mechanism. Gene silencing in cultured EC and EC-specific genetic deletion in mice demonstrated that TWIST1 promoted atherosclerosis by inducing inflammation and enhancing EC proliferation associated with vascular leakiness. CONCLUSIONS: TWIST expression promotes developmental angiogenesis by inducing EC proliferation and migration. In addition to its role in development, TWIST is expressed preferentially at low shear stress regions of adult arteries where it promotes atherosclerosis by inducing EC proliferation and inflammation. Thus, pleiotropic functions of TWIST control vascular disease and development.


Asunto(s)
Aterosclerosis/metabolismo , Velocidad del Flujo Sanguíneo/fisiología , Endotelio Vascular/metabolismo , Proteínas Nucleares/biosíntesis , Proteína 1 Relacionada con Twist/biosíntesis , Animales , Aterosclerosis/patología , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Células Endoteliales/metabolismo , Células Endoteliales/patología , Endotelio Vascular/patología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Porcinos , Pez Cebra
11.
Physiol Plant ; 157(1): 108-18, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26565659

RESUMEN

Plant circumnutation is a helical movement of growing organs such as shoots and roots. Gravitropic response is hypothesized to act as an external oscillator in shoot circumnutation, although this is subject to debate. The relationship between circumnutational movement and gravitropic response in roots remains unknown. In this study, we analyzed circumnutation of agravitropic roots using the ageotropum pea (Pisum sativum) mutant, and compared it with that of wild-type (cv. Alaska) pea roots. We further examined the relationship of gravitropic response to circumnutation of Alaska seedling roots by removing the gravisensing tissue (the root cap) and by treating the roots with auxin transport inhibitors. Alaska roots displayed circumnutational movements with a period of approximately 150 min, whereas ageotropum roots did not exhibit distinct circumnutational movement. Removal of the root cap in Alaska roots reduced gravitropic response and circumnutational movements. Treatment of Alaska roots with auxin transport inhibitors, 2,3,5-triiodobenzoic acid (TIBA) and N-(1-naphthyl)phthalamic acid (NPA), dramatically reduced gravitropic response and circumnutational movements. These results suggest that a gravity-regulated auxin transport is involved in circumnutation of pea seedling roots.


Asunto(s)
Gravitropismo/fisiología , Ácidos Indolacéticos/antagonistas & inhibidores , Pisum sativum/fisiología , Reguladores del Crecimiento de las Plantas/farmacología , Raíces de Plantas/fisiología , Transporte Biológico , Gravitropismo/efectos de los fármacos , Ácidos Indolacéticos/metabolismo , Pisum sativum/efectos de los fármacos , Ftalimidas/farmacología , Reguladores del Crecimiento de las Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Plantones/efectos de los fármacos , Plantones/fisiología , Ácidos Triyodobenzoicos/farmacología
12.
Arterioscler Thromb Vasc Biol ; 34(10): 2199-205, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24947523

RESUMEN

Atherosclerosis is a chronic inflammatory disease of arteries that develops preferentially at branches and bends that are exposed to disturbed blood flow. Vascular function is modified by flow, in part, via the generation of mechanical forces that alter multiple physiological processes in endothelial cells. Shear stress has profound effects on vascular inflammation; high uniform shear stress prevents leukocyte recruitment to the vascular wall by reducing endothelial expression of adhesion molecules and other inflammatory proteins, whereas low oscillatory shear stress has the opposite effects. Here, we review the molecular mechanisms that underpin the effects of shear stress on endothelial inflammatory responses. They include shear stress regulation of inflammatory mitogen-activated protein kinase and nuclear factor-κB signaling. High shear suppresses these pathways through the induction of several negative regulators of inflammation, whereas low shear promotes inflammatory signaling. Furthermore, we summarize recent studies indicating that inflammatory signaling is highly sensitive to pulse wave frequencies, magnitude, and direction of flow. Finally, the importance of systems biology approaches (including omics studies and functional screening) to identify novel mechanosensitive pathways is discussed.


Asunto(s)
Aterosclerosis/patología , Células Endoteliales/patología , Endotelio Vascular/patología , Inflamación/patología , Mecanotransducción Celular , Animales , Aterosclerosis/genética , Aterosclerosis/metabolismo , Aterosclerosis/fisiopatología , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Regulación de la Expresión Génica , Hemodinámica , Humanos , Inflamación/genética , Inflamación/metabolismo , Inflamación/fisiopatología , Mediadores de Inflamación/metabolismo , Flujo Sanguíneo Regional , Estrés Mecánico
13.
Development ; 138(9): 1783-94, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21447554

RESUMEN

The development of the different muscles within the somite is a complex process that involves the Hedgehog (Hh) signaling pathway. To specify the proper number of muscle cells and organize them spatially and temporally, the Hh signaling pathway needs to be precisely regulated at different levels, but only a few factors external to the pathway have been described. Here, we report for the first time the role of the STAR family RNA-binding protein Quaking A (QkA) in somite muscle development. We show in zebrafish that the loss of QkA function affects fast muscle fiber maturation as well as Hh-induced muscle derivative specification and/or morphogenesis. Mosaic analysis reveals that fast fiber maturation depends on the activity of QkA in the environment of fast fiber progenitors. We further show that Hh signaling requires QkA activity for muscle development. By an in silico approach, we screened the 3'UTRs of known Hh signaling component mRNAs for the Quaking response element and found the transcription factor Gli2a, a known regulator of muscle fate development. Using destabilized GFP as a reporter, we show that the gli2a mRNA 3'UTR is a functional QkA target. Consistent with this notion, the loss of QkA function rescued slow muscle fibers in yot mutant embryos, which express a dominant-negative Gli2a isoform. Thus, our results reveal a new mechanism to ensure muscle cell fate diversity by fine-tuning of the Hh signaling pathway via RNA-binding proteins.


Asunto(s)
Proteínas Hedgehog/fisiología , Desarrollo de Músculos/genética , Proteínas de Unión al ARN/fisiología , Proteínas de Pez Cebra/fisiología , Animales , Animales Modificados Genéticamente , Tipificación del Cuerpo/genética , Tipificación del Cuerpo/fisiología , Mapeo Cromosómico , Embrión no Mamífero , Genes Recesivos , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Morfogénesis/genética , Morfogénesis/fisiología , Desarrollo de Músculos/fisiología , Fibras Musculares de Contracción Rápida/metabolismo , Fibras Musculares de Contracción Rápida/fisiología , Fibras Musculares de Contracción Lenta/metabolismo , Fibras Musculares de Contracción Lenta/fisiología , Mutación/fisiología , Proteínas de Unión al ARN/genética , Transducción de Señal/genética , Transducción de Señal/fisiología , Pez Cebra/embriología , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
14.
Histopathology ; 65(6): 764-74, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25040719

RESUMEN

AIMS: Granular cell tumours (GCTs) are uncommon in the gastrointestinal tract, particularly in the colorectum. Herein, we report a series of 30 colorectal GCTs and discuss the properties of colorectal GCTs based on histopathological and immunohistochemical studies. METHODS AND RESULTS: Searching the surgical pathology files identified 30 cases of colorectal GCTs for 2005-2013. A broad panel of antibodies including neural and macrophage markers were used for immunohistochemical evaluation. Colorectal GCTs predominantly involved the right colon and showed increased nuclear atypia including nuclear pleomorphism and nuclear spindling. All 24 cases with mucosal tumour components had infiltrative growth patterns within the mucosa. In all available cases, diffuse strong immunopositivity was observed for S100 and SOX10 of schwannian differentiation markers, as well as for CD68. Other neuronal lineage markers, including CD56, neuron-specific enolase, nestin, and synaptophysin showed consistently high expression rates. The immunohistochemical results are suggestive for a neural origin of GCTs. CONCLUSION: Histopathological and immunohistochemical features of colorectal GCTs were delineated in this large series of 30 colorectal GCTs. Although the incidence of GCTs is relatively low, clinicians and pathologists need to be aware of GCT in the differential diagnosis.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias Colorrectales/patología , Tumor de Células Granulares/patología , Adulto , Anciano , Neoplasias Colorrectales/metabolismo , Femenino , Tumor de Células Granulares/metabolismo , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad
15.
Chemosphere ; 355: 141798, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38548074

RESUMEN

The reuse of waste papers by conversion into valuable carbon materials has received considerable attention for diverse applications such as energy storage and water purification. However, traditional methods for converting waste papers into materials with suitable properties for specific applications are often complex and ineffective, involving consecutive carbonization and activation steps. Herein, we propose a simple one-step microwave (MW)-assisted synthesis for preparing waste paper-derived porous carbons (WPCs) for energy storage and water purification. Through a 30-min synthesis, WPCs with graphitic structure and high specific surface area were successfully produced. The fabricated WPCs exhibited outstanding charge storage capability with a maximum specific capacitance of 237.7 F g-1. Additionally, the WPC demonstrates a high removal efficiency for various dyes, achieving a maximum removal efficiency of 95.0% for methylene blue. The developed one-step MW synthesis not only enables the production of porous carbon from waste paper, but also offers a viable approach to address solid waste management challenges while simultaneously yielding valuable materials.


Asunto(s)
Grafito , Purificación del Agua , Carbono/química , Porosidad , Microondas
16.
PLoS One ; 19(2): e0298815, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38363779

RESUMEN

OBJECTIVE: To investigate the anti-cancer efficacy of ENB101-LNP, an ionizable lipid nanoparticles (LNPs) encapsulating siRNA against E6/E7 of HPV 16, in combination therapy with cisplatin in cervical cancer in vitro and in vivo. METHODS: CaSki cells were treated with ENB101-LNP, cisplatin, or combination. Cell viability assessed the cytotoxicity of the treatment. HPV16 E6/E7 gene knockdown was verified with RT-PCR both in vitro and in vivo. HLA class I and PD-L1 were checked by flow cytometry. A xenograft model was made using CaSki cells in BALB/c nude mice. To evaluate anticancer efficacy, mice were grouped. ENB101-LNP was given three times weekly for 3 weeks intravenously, and cisplatin was given once weekly intraperitoneally. Tumor growth was monitored. On day 25, mice were euthanized; tumors were collected, weighed, and imaged. Tumor samples were analyzed through histopathology, immunostaining, and western blot. RESULTS: ENB101-LNP and cisplatin synergistically inhibit CaSki cell growth. The combination reduces HPV 16 E6/E7 mRNA and boosts p21 mRNA, p53, p21, and HLA class I proteins. In mice, the treatment significantly blocked tumor growth and promoted apoptosis. Tumor inhibition rates were 29.7% (1 mpk ENB101-LNP), 29.6% (3 mpk), 34.0% (cisplatin), 47.0% (1 mpk ENB101-LNP-cisplatin), and 68.8% (3 mpk ENB101-LNP-cisplatin). RT-PCR confirmed up to 80% knockdown of HPV16 E6/E7 in the ENB101-LNP groups. Immunohistochemistry revealed increased p53, p21, and HLA-A expression with ENB101-LNP treatments, alone or combined. CONCLUSION: The combination of ENB101-LNP, which inhibits E6/E7 of HPV 16, with cisplatin, demonstrated significant anticancer activity in the xenograft mouse model of cervical cancer.


Asunto(s)
Liposomas , Nanopartículas , Proteínas Oncogénicas Virales , Neoplasias del Cuello Uterino , Femenino , Humanos , Animales , Ratones , ARN Interferente Pequeño/genética , Cisplatino/farmacología , Cisplatino/uso terapéutico , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Proteína p53 Supresora de Tumor/genética , Ratones Desnudos , Xenoinjertos , Línea Celular Tumoral , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , ARN Mensajero/genética
17.
Clin Chim Acta ; 557: 117872, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38471630

RESUMEN

The goal of this study is to create a highly sensitive time-resolved fluorescence lateral flow immunoassay (TRF-LFIA) capable of concurrently measuring glial fibrillary acidic protein (GFAP) and the N-terminal fragment of B-type natriuretic peptide precursor (NT-proBNP). This assay is designed as a diagnostic tool and aims to provide an algorithm for stroke management, specifically for distinguishing between Ischemic stroke (IS) and Hemorrhagic stroke (HS). However, LFIA to quantify simultaneous serum NT-proBNP and GFAP are not yet available. We have developed and validated a novel TRF-LFIA for the simultaneous quantitative detection of NT-proBNP and GFAP. The sensitivity and reproducibility of the immunoassay were significantly improved by employing specific monoclonal antibodies linked to europium nanoparticles (EuNPs) that specifically target NT-proBNP and GFAP. The detection area on the nitrocellulose membrane featured sandwich-style complexes containing two test lines for NT-proBNP and GFAP, and one Control line. The fluorescence intensity of these test lines and control line was measured using an in-house developed Exdia TRF-Plus analyzer. As proof-of-concept, we enrolled patients suspected of having a stroke who were admitted within a specific time frame (6 h). A small amount of clinical specimen (serum) was used. To optimize the LFIA, an EuNPs conjugated antibodies were investigated to improve the detection sensitivity and decrease the background signal as well shorten the detection time. The Exdia TRF-LFIA cartridge offers a wide linear dynamic detection range, rapid detection, high sensitivity, and specificity. The limit of detection was determined to be 98 pg/mL for NT-proBNP and 68 pg/mL for GFAP, with minimal cross-reactivity. There were 200 clinical human serum samples that were used to evaluate this platform with high correlation. By combining the results of NT-proBNP and GFAP, we formulated an algorithm for the clinical assessment of Ischemic Stroke (IS) and Hemorrhagic Stroke (HS). According to our proposed algorithm, the combination of GFAP and NT-proBNP emerged as the most effective biomarker combination for distinguishing between IS and HS. Exdia TRF-LFIA shows great potential as a supplemental method for in vitro diagnostics in the laboratory or in other point-of-care testing (POCT) applications. Its development substantially decreases the diagnosis time for IS and HS. The proposed algorithm not only minimizes treatment delays but also lowers medical costs for patients.


Asunto(s)
Accidente Cerebrovascular Hemorrágico , Accidente Cerebrovascular Isquémico , Nanopartículas del Metal , Accidente Cerebrovascular , Humanos , Péptido Natriurético Encefálico , Proteína Ácida Fibrilar de la Glía , Reproducibilidad de los Resultados , Europio , Accidente Cerebrovascular/diagnóstico , Fragmentos de Péptidos , Biomarcadores
18.
Front Pharmacol ; 14: 1242970, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37711172

RESUMEN

Background: Interleukin-2 (IL-2) is the first cancer therapeutic agent with an immunomodulatory function. Although it has been experimentally proven to be effective against metastatic renal cell carcinoma and metastatic melanoma, the clinical application of high-dose IL-2 (HDIL-2) has been limited because of its short half-life and severe side effects, such as vascular leakage syndrome (VLS) or capillary leaky syndrome (CLS). However, methods for overcoming this issue have not yet been identified. Methods: We discovered CU06-1004, an endothelial dysfunction blocker, through a previous study, and co-treated with IL-2 immunotherapy to confirm its inhibitory effect on HDIL-2-induced endothelial permeability. CU06-1004 was co-administered with HDIL-2 for 4 days in an in vivo mouse model. After drug injection, the mice were sacrificed, and Evans blue staining was performed. Results: In vitro, HDIL-2 treatment decreased HUVEC stability, which was rescued by co-treatment with CU06-1004. In our mouse model, co-administration of CU06-1004 and HDIL-2 prevented HDIL-2-induced vascular leakage by normalizing endothelial cells. Notably, the HDIL-2 and CU06-1004 combination therapy considerably reduced tumor growth in the B16F10 melanoma mouse model. Conclusion: Our data suggest that CU06-1004 acts as a potential anticancer drug candidate, not only by preventing HDIL-2-induced VLS but also by enhancing the anticancer effects of HDIL-2 immunotherapy.

19.
Eur J Pharmacol ; 939: 175427, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36509133

RESUMEN

Retinal vascular diseases are the leading cause of blindness worldwide. These diseases have common disease mechanisms including vascular endothelial growth factor (VEGF) signaling, hypoxia, and inflammation. Treatment of these diseases with laser therapy, anti-VEGF injections and/or steroids has significantly improved clinical outcomes. However, these strategies do not address the underlying cause of the pathology and may have harmful side effects. Pathological processes that damage retinal vessels result in vascular occlusion and impairment of the barrier properties of retinal endothelial cells, leading to excessive vascular leakage. Therefore, a new therapeutic approach is needed for the treatment of retinal vascular disease. We were able to confirm that oral administration of CU06-1004, an endothelial dysfunction blocker, inhibited retinal vascular leakage induced by vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang2). Interestingly, oral administration of CU06-1004 prevented excessive vascular leakage in the diabetic retinopathy model. In addition, CU06-1004 inhibited angiogenesis and confirmed vascular stabilization in the oxygen-induced retinopathy model and laser-induced CNV model. Taken together, CU06-1004 could be a potential therapeutic agent for the treatment of retinal vascular diseases.


Asunto(s)
Retinopatía Diabética , Enfermedades de la Retina , Humanos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Permeabilidad Capilar , Células Endoteliales , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/complicaciones , Enfermedades de la Retina/metabolismo , Factores de Crecimiento Endotelial Vascular/metabolismo , Factores de Crecimiento Endotelial Vascular/farmacología , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/etiología , Administración Oral
20.
Fluids Barriers CNS ; 20(1): 9, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36726154

RESUMEN

BACKGROUND: Age-related changes in the cerebrovasculature, including blood-brain barrier (BBB) disruption and vascular dementia, are emerging as potential risks for many neurodegenerative diseases. Therefore, the endothelial cells that constitute the cerebrovasculature may play key roles in preventing brain injury. Our previous study showed that CU06-1004, an endothelial cell dysfunction blocker, prevented vascular leakage, enhanced vascular integrity in ischemic reperfusion injury, and promoted the normalization of tumor vasculature. Here, we evaluated the effects of CU06-1004 on age-related cerebrovascular functional decline in the aged mouse brain. RESULTS: In this study, we investigated the protective effects of CU06-1004 against oxidative stress-induced damage in human brain microvascular endothelial cells (HBMECs). HBMECs were treated with hydrogen peroxide (H2O2) to establish an oxidative stress-induced model of cellular injury. Compared with H2O2 treatment alone, pretreatment of HBMECs with CU06-1004 considerably reduced oxidative stress-induced cytotoxicity, reactive oxygen species generation, senescence-associated ß-galactosidase activity, senescence marker expression, and the expression levels of inflammatory proteins. Based on the observed cytoprotective effects of CU06-1004 in HBMECs, we examined whether CU06-1004 displayed protective effects against cerebrovascular aging in mice. Long-term administration of CU06-1004 alleviated age-associated cerebral microvascular rarefaction and cerebrovascular senescence in the aged mouse brain. CU06-1004 supplementation also reduced the extravasation of plasma IgG by improving BBB integrity in the aged mouse brain, associated with reductions in neuronal injury. A series of behavioral tests also revealed improved motor and cognitive functions in aged mice that received long-term CU06-1004 administration. CONCLUSIONS: These findings suggest that CU06-1004 may represent a promising therapeutic approach for delaying age-related cerebrovascular impairment and improving cognitive function in old age.


Asunto(s)
Barrera Hematoencefálica , Células Endoteliales , Humanos , Ratones , Animales , Barrera Hematoencefálica/metabolismo , Células Endoteliales/metabolismo , Peróxido de Hidrógeno/metabolismo , Envejecimiento , Modelos Animales de Enfermedad
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