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1.
Nat Immunol ; 13(6): 560-8, 2012 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-22561606

RESUMO

Signaling via the T cell antigen receptor (TCR) during the CD4(+)CD8(+) double-positive developmental stage determines thymocyte selection and lineage commitment. Here we describe a previously uncharacterized T cell-expressed protein, Tespa1, with critical functions during the positive selection of thymocytes. Tespa1(-/-) mice had fewer mature thymic CD4(+) and CD8(+) T cells, which reflected impaired thymocyte development. Tespa1 associated with the TCR signaling components PLC-γ1 and Grb2, and Tespa1 deficiency resulted in attenuated TCR signaling, as reflected by defective activation of the Erk-AP-1 and Ca(2+)-NFAT pathways. Our findings demonstrate that Tespa1 is a component of the TCR signalosome and is essential for T cell selection and maturation through the regulation of TCR signaling during T cell development.


Assuntos
Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Timo/imunologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular/imunologia , Clonagem Molecular , Proteína Adaptadora GRB2/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Dados de Sequência Molecular , Fosfolipase C gama/imunologia , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Transdução de Sinais/imunologia , Timo/citologia
2.
J Environ Manage ; 366: 121688, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971059

RESUMO

Heavy metals (HMs) contained terrestrial ecosystems are often significantly display the antibiotic resistome in the pristine area due to increasing pressure from anthropogenic activity, is complex and emerging research interest. This study investigated that impact of chromium (Cr), nickel (Ni), cobalt (Co) concentrations in serpentine soil on the induction of antibiotic resistance genes and antimicrobial resistance within the native bacterial community as well as demonstrated their metabolic fingerprint. The full-length 16S-rRNA amplicon sequencing observed an increased abundance of Firmicutes, Actinobacteriota, and Acidobacteriota in serpentine soil. The microbial community in serpentine soil displayed varying preferences for different carbon sources, with some, such as carbohydrates and carboxylic acids, being consistently favored. Notably, 27 potential antibiotic resistance opportunistic bacterial genera have been identified in different serpentine soils. Among these, Lapillicoccus, Rubrobacter, Lacibacter, Chloroplast, Nitrospira, Rokubacteriales, Acinetobacter, Pseudomonas were significantly enriched in high and medium HMs concentrated serpentine soil samples. Functional profiling results illustrated that vancomycin resistance pathways were prevalent across all groups. Additionally, beta-lactamase, aminoglycoside, tetracycline, and vancomycin resistance involving specific bio-maker genes (ampC, penP, OXA, aacA, strB, hyg, aph, tet(A/B), otr(C), tet(M/O/Q), van(A/B/D), and vanJ) were the most abundant and enriched in the HMs-contaminated serpentine soil. Overall, this study highlighted that heavy-metal enriched serpentine soil is potential to support the proliferation of bacterial antibiotic resistance in native microbiome, and might able to spread antibiotic resistance to surrounding environment.

3.
Molecules ; 28(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36838679

RESUMO

Natural polysaccharides with high viscosity, good thermal stability, and biocompatibility can improve the mechanical properties of inorganic silica aerogels and enhance their application safety. However, the effects of the preparation methods of polysaccharide-silica aerogels on their microstructure and application properties have not been systematically studied. To better investigate the effect of the microstructure on the properties of aerogel materials, two aerogels with different structures were prepared using Konjac glucomannan (KGM) and tetraethoxysilane (TEOS) via physical blending (KTB) and co-precursor methods (KTC), respectively. The structural differences between the KTB and KTC aerogels were characterized, and the thermal insulation and fire-retardant properties were further investigated. The compressive strength of the KTC aerogels with a cross-linked interpenetrating network (IPN) structure was three times higher than that of the KTB aerogels, while their thermal conductivity was 1/3 of that of the KTB aerogels. The maximum limiting oxygen index (LOI) of the KTC aerogels was 1.4 times, the low peak heat release rate (PHRR) was reduced by 61.45%, and the lowest total heat release (THR) was reduced by 41.35% compared with the KTB aerogels. The results showed that the KTC aerogels with the IPN have better mechanical properties, thermal insulation, and fire-retardant properties than the simple physically blending KTB aerogels. This may be due to the stronger hydrogen-bonding interactions between KGM and silica molecules in the KTC aerogels under the unique forcing effect of the IPN, thus enhancing their structural stability and achieving complementary properties. This work will provide new ideas for the microstructure design of aerogels and the research of new thermal insulation and fire-retardant aerogels.


Assuntos
Retardadores de Chama , Mananas , Força Compressiva , Dióxido de Silício
4.
Opt Express ; 28(2): 1103-1113, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32121826

RESUMO

The optical waveguide is a lightweight and portable scheme for augmented reality near-eye display devices. However, the surface roughness of the waveguide affects its imaging performance, which has not been studied. In this work, we investigate the light scattering caused by the root-mean-square roughness of the waveguide surface and present two methods to numerically analyze the modulation transfer function (MTF) of the display system. Here, we consider the effects of different surface roughness, incident angle, and incident wavelength on the scattering distribution when other conditions are constant. For a simplified optical waveguide display system, the MTF degradation and the variation of the tolerance is calculated. And when the MTF (@ 40 cycles/mm) is required to be 0.3 and the incident angles of the total reflection surface are 45°, 55°, 65° and 75°, the random surface error (RSE) tolerances are 0.207λ0, 0.255λ0, 0.347λ0 and 0.566λ0 (λ0=0.5461µm), respectively. We find a formula descripting the relationship between RSE tolerance and incident angle. If the RSE tolerance exceeds the value of the formula at an angle, the imaging quality of the system will drop significantly. The formula can predict tolerances and incident angles and provide basic tool for imaging quality analysis and manufacturing for optical waveguide AR/VR display systems.

5.
Eur J Clin Invest ; 50(10): e13332, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32589285

RESUMO

BACKGROUND: This study aimed to summarize the association between diabetes mellitus (DM) and the incidence of lung cancer using a meta-analysis of cohort studies. MATERIALS AND METHODS: We systematically searched PubMed, Embase and the Cochrane Library to identify potential cohort studies. Relative risk (RR) was used to calculate the association between DM and the risk of lung cancer. Subgroup analysis, sensitivity analysis and test for publication bias were performed. Twenty cohort studies were selected. RESULTS: The participants with DM showed little or no significant effect on the risk of lung cancer (RR: 1.10; 95% CI: 0.99-1.23; P = .087). DM was not associated with the risk of lung cancer in men (RR: 1.11; 95%CI: 0.92-1.35; P = .270), but a significant association was observed in women (RR: 1.18; 95%CI: 1.10-1.28; P < .001). Subgroup analysis suggested that smoker status was confounding variables that could bias the relationship between DM and the incidence of lung cancer. CONCLUSIONS: This meta-analysis suggests that DM has no significant impact on the incidence of lung cancer in men but has a harmful effect on women.


Assuntos
Diabetes Mellitus/epidemiologia , Neoplasias Pulmonares/epidemiologia , Humanos
6.
J Org Chem ; 85(10): 6498-6508, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32329338

RESUMO

An alternative process of Pd-catalyzed C-4 selective coupling of 2,4-dichloropyridines with boronic esters was developed, which afforded 24 examples of C-4 coupled pyridines in moderate to good yields. After further arylation, 21 examples of C-2, C-4 diarylated pyridines with a significant photophysical property were obtained, which were applied as pyridine-based dyes into live-cell imaging with good biocompatibility and low toxicity.


Assuntos
Corantes , Paládio , Catálise , Células , Estrutura Molecular , Piridinas
7.
Acta Biochim Biophys Sin (Shanghai) ; 51(9): 945-952, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31435645

RESUMO

The relationship of carcinogenesis and DNA methyltransferases has attracted extensive attention in tumor research. We reported previously that inhibition of de novo DNA methyltransferase 3a (Dnmt3a) in murine B16 melanoma cells significantly suppressed tumor growth and metastasis in xenografted mouse model. Here, we further demonstrated that knockdown of Dnmt3a enhanced the proliferation in anchor-independent conditions of B16 cells, but severely disrupted its multipotent differentiation capacity in vitro. Furthermore, transforming growth factor ß1, a key trigger in stem cell differentiation and tumor cell epithelial-mesenchymal transition (EMT), mainly induced apoptosis, but not EMT in Dnmt3a-deficient B16 cells. These data suggested that Dnmt3a is required for maintaining the tumor stemness of B16 cells and it assists B16 cells to escape from death during cell differentiation. Thus it is hypothesized that not only extraordinary self-renewal ability, but also the capacity of multipotent differentiation is necessary for the melanoma tumorigenesis. Inhibition of multipotent differentiation of tumor cells may shed light on the tumor treatment.


Assuntos
Carcinogênese/metabolismo , DNA (Citosina-5-)-Metiltransferases/fisiologia , Melanoma Experimental/patologia , Células-Tronco Neoplásicas/patologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Diferenciação Celular , Linhagem Celular Tumoral , DNA Metiltransferase 3A , Transição Epitelial-Mesenquimal , Camundongos , Camundongos Endogâmicos C57BL
8.
Opt Express ; 26(25): 32802-32811, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30645442

RESUMO

We propose an integrated holographic waveguide display system. An infrared volume holographic grating (IVHG) and a visible light grating are recorded on the same waveguide to achieve the purpose of a common light path for system miniaturization. Simulated and experimental results verify the feasibility of this method. The coupling efficiencies of the infrared module for eye tracking and the visible light module for augmented reality (AR) display are 40% and 45%. The holographic waveguide has a weight of only 4.3 grams. It is believed that this technique is a good way to achieve a light and thin eye tracking near-eye display.

9.
Acta Biochim Biophys Sin (Shanghai) ; 50(7): 666-675, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29860267

RESUMO

Multiple sclerosis and its primary animal model, experimental autoimmune encephalomyelitis (EAE), are inflammatory diseases of the central nervous system (CNS) characterized by immune-mediated demyelination and neurodegeneration that may be mediated by inhibition of the nuclear factor-κB (NF-κB) signaling pathway. Gpr97, encoded by Adgrg3, has been reported to regulate the activity of NF-κB. In this study, using a previously established Adgrg3-knockout mouse model, we investigated the roles of Gpr97 in the development of autoimmune CNS disease in mice. We found a marked increase in the expression of Adgrg3 in spinal cords of mice with EAE. Adgrg3-deficient (Adgrg3-/-) mice with EAE exhibited increases in peak severity and the cumulative disease score compared with littermate controls, followed by a notable increase of leukocyte infiltration and more extensive demyelination. The percentages of Th1/Th17 cells in the CNS were significantly increased in Adgrg3-/- mice and accompanied by high levels of interleukin (IL)-6, interferon-γ, tumor necrosis factor-α, and IL-17. An in vitro culture assay verified that Gpr97 regulated proinflammatory cytokine production. Taken together, our results show that Gpr97 plays an important role in the development of EAE and may have a therapeutic potential for the treatment of CNS autoimmunity.


Assuntos
Sistema Nervoso Central/imunologia , Citocinas/imunologia , Encefalomielite Autoimune Experimental/imunologia , Receptores Acoplados a Proteínas G/imunologia , Animais , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Citocinas/genética , Citocinas/metabolismo , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/metabolismo , Feminino , Interferon gama/genética , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-17/metabolismo , Interleucina-6/genética , Interleucina-6/imunologia , Interleucina-6/metabolismo , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/patologia , Células Th17/imunologia , Células Th17/metabolismo , Células Th17/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
10.
Med Sci Monit ; 23: 535-541, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-28133358

RESUMO

BACKGROUND Vitamin D is an import regulator of T helper 17 (Th17) differentiation, but our understanding of the underlying mechanisms remains limited. In the present study, we aimed to detect the expression levels of microRNAs (miRNAs) during human Th17 differentiation and evaluate the effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), the bioactive form of vitamin D, on Th17 differentiation and miRNA expression. MATERIAL AND METHODS We cultured human peripheral blood mononuclear cells (PBMC) in vitro and activated them with anti-CD3 and anti-CD28 antibodies in the presence of Th17-promoting cytokines interleukin (IL)-23, IL-1ß, TGF-ß1, and IL-6 for 72 hours. 1,25(OH)2D3 was added to the medium at a final concentration of 100 nM on day 0. The production of IL-17A in culture medium was detected by enzyme-linked immunosorbent assay (ELISA). The expression levels of miRNAs during Th17 differentiation were determined by quantitative polymerase chain reaction (qPCR). RESULTS Six miRNAs were found to be dysregulated during human Th17 differentiation. Of these miRNAs, hsa-miR-155 was significantly up-regulated (median fold change: 3.61, P<0.05), whereas hsa-miR-20b, hsa-miR-21, hsa-miR-181a, hsa-miR-210, and hsa-miR-301a were significantly down-regulated (median fold change: 0.44, 0.37, 0.18, 0.15, and 0.26, respectively, P<0.05). 1,25(OH)2D3 treatment significantly decreased IL-17A production (median [interquartile range], 745.7 [473.5] pg/mL vs. 2535.4 [2153.3] pg/mL, P<0.05). However, expression of these miRNAs was not changed after 1,25(OH)2D3 treatment. CONCLUSIONS 1,25(OH)2D3 suppressed human Th17 differentiation without affecting miRNA expression.


Assuntos
Calcitriol/farmacologia , MicroRNAs/biossíntese , Células Th17/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/farmacologia , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucina-17/biossíntese , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células Th17/citologia , Células Th17/metabolismo , Vitaminas/farmacologia
11.
Nucleic Acids Res ; 43(3): 1549-61, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25609696

RESUMO

The Krüppel-associated box (KRAB) domain is a transcription repression module from the largest family of transcriptional regulators encoded by higher vertebrates. We developed a drug-controllable regulation system based on an artificial KRAB-containing repressor (tTS) that targets the endogenous Hprt gene to explore the regulatory mechanism and molecular basis of KRAB-containing regulators within the context of an endogenous gene in vivo. We show that KRAB can mediate irreversible and reversible regulation of endogenous genes in mouse that is dependent on embryonic developmental stage. KRAB-induced stable DNA methylation within the KRAB binding region during the early embryonic stage, resulting in irreversible gene repression. In later stages, KRAB mainly induced de-acetylation and methylation of histone, resulting in reversible gene repression. Thus, we have characterized the KRAB-mediated regulation system within the context of an endogenous gene and multiple spatiotemporal ranges, thereby providing a basis for identifying the function of KRAB-containing regulators and aiding development of novel KRAB-based gene regulation tools in vivo.


Assuntos
Proteínas de Transporte/fisiologia , Cromatina/metabolismo , Regulação da Expressão Gênica , Proteínas Nucleares/fisiologia , Proteínas Repressoras/fisiologia , Animais , Sequência de Bases , Células Cultivadas , Imunoprecipitação da Cromatina , Metilação de DNA , Primers do DNA , Epigênese Genética , Hipoxantina Fosforribosiltransferase/genética , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase em Tempo Real
12.
Am J Med Genet B Neuropsychiatr Genet ; 174(8): 828-838, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28981195

RESUMO

Nhe5, a Na+ /H+ exchanger, is predominantly expressed in brain tissue and is proposed to act as a negative regulator of dendritic spine growth. Up to now, its physiological function in vivo remains unclear. Here we show that Nhe5-deficient mice exhibit markedly enhanced learning and memory in Morris water maze, novel object recognition, and passive avoidance task. Meanwhile, the pre- and post-synaptic components, synaptophysin (Syn) and post-synaptic density 95 (PSD95) expression levels were found increased in hippocampal regions lacking of Nhe5, suggesting a possible alterations in neuronal synaptic structure and function in Nhe5-/- mice. Further study reveals that Nhe5 deficiency leads to higher Bdnf expression levels, followed by increased phosphorylated TrkB and PLCγ levels, indicating that Bdnf/TrkB signaling is activated due to Nhe5 deficiency. Moreover, the corresponding brain regions of Nhe5-/- mice display elevated ERK/CaMKII/CREB phosphorylation levels. Taken together, these findings uncover a novel physiological function of Nhe5 in regulating learning and memory, further implying Nhe5 as a potential therapeutic target for improving cognition.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Receptor trkB/metabolismo , Trocadores de Sódio-Hidrogênio/fisiologia , Animais , Comportamento Animal , Encéfalo/citologia , Encéfalo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/citologia , Neurônios/metabolismo , Receptor trkB/genética , Transdução de Sinais , Regulação para Cima
13.
Acta Biochim Biophys Sin (Shanghai) ; 48(11): 1058-1065, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27649891

RESUMO

PRSS37, a putative trypsin-like serine protease, is highly conserved during mammalian evolution as revealed by multiple sequence alignment. Mice deficient for Prss37 gene exhibit male infertility, but their mating behavior, spermatogenesis, sperm morphology, and motility remain unaffected, similar to a situation called unexplained male infertility (UMI) in men (human being). Here, we demonstrated that PRSS37 is restrictively expressed in human testis, where it is mainly located in the elongating and elongated spermatids during spermiogenesis as shown by immunohistochemical analysis of normal human testicular sections. In mature sperm, PRSS37 appears in the acrosome region and diminishes during acrosome reaction. Further examination reveals that PRSS37 contents in sperm from patients with UMI are dramatically lower than those in sperm from men with proven fertility or from sperm donors. Sperm with low PRSS37 contents exhibit abnormal activation of the proacrosin/acrosin system and premature proteolysis of ADAM2, which may impair the functional competence of human sperm in vivo However, the in vitro fertilization outcomes of sperm with low PRSS37 contents are not affected. Together, these data implicate an important role of PRSS37 for male fertility. PRSS37 can be used as a potential molecular biomarker for evaluating sperm fertilization capability in vivo but not in vitro.


Assuntos
Infertilidade Masculina/metabolismo , Serina Proteases/metabolismo , Espermatozoides/metabolismo , Acrossomo/metabolismo , Reação Acrossômica , Estudos de Casos e Controles , Fertilinas/metabolismo , Fertilização in vitro , Perfilação da Expressão Gênica , Humanos , Masculino , Proteólise , Serina Proteases/genética
14.
Proc Natl Acad Sci U S A ; 110(16): 6459-64, 2013 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-23553835

RESUMO

Retinoic acid inducible gene I (RIG-I) senses viral RNAs and triggers innate antiviral responses through induction of type I IFNs and inflammatory cytokines. However, whether RIG-I interacts with host cellular RNA remains undetermined. Here we report that Rig-I interacts with multiple cellular mRNAs, especially Nf-κb1. Rig-I is required for NF-κB activity via regulating Nf-κb1 expression at posttranscriptional levels. It interacts with the multiple binding sites within 3'-UTR of Nf-κb1 mRNA. Further analyses reveal that three distinct tandem motifs enriched in the 3'-UTR fragments can be recognized by Rig-I. The 3'-UTR binding with Rig-I plays a critical role in normal translation of Nf-κb1 by recruiting the ribosomal proteins [ribosomal protein L13 (Rpl13) and Rpl8] and rRNAs (18S and 28S). Down-regulation of Rig-I or Rpl13 significantly reduces Nf-κb1 and 3'-UTR-mediated luciferase expression levels. These findings indicate that Rig-I functions as a positive regulator for NF-κB signaling and is involved in multiple biological processes in addition to host antivirus immunity.


Assuntos
RNA Helicases DEAD-box/metabolismo , Regulação da Expressão Gênica/fisiologia , NF-kappa B/metabolismo , RNA Mensageiro/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Northern Blotting , Western Blotting , Proteína DEAD-box 58 , RNA Helicases DEAD-box/genética , Imunofluorescência , Imunoprecipitação , Luciferases , Camundongos , Camundongos Knockout , Análise em Microsséries , Simulação de Dinâmica Molecular , NF-kappa B/genética , Interferência de RNA , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Ribossômicas/metabolismo
15.
Int J Neurosci ; 126(3): 205-12, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26000455

RESUMO

PURPOSE: Polymorphisms in the genes encoding interleukin-23 receptor (IL23R) and the p40 subunit of IL-12/23 (IL12B) have been implicated in multiple sclerosis (MS) risk. However, results of different studies are inconsistent. Our aim was to perform a meta-analysis on this topic. METHODS: We assessed two variants (rs10889677 and rs7517847) of IL23R and the A1188C polymorphism (rs3212227) of IL12B. Electronic databases (PubMed, Web of Science and Scopus) were searched for eligible studies published until September 2014. Odds ratio (OR) and 95% confidence interval (95% CI) were used to investigate the strength of association in dominant, recessive, homozygote and allelic comparison models. RESULTS: Seven case-control studies with 2250 MS patients and 2320 controls were included in this meta-analysis. The pooled results showed no association of rs10889677 and rs7517847 with MS risk in any of the genetic models. Although the pooled analysis showed an association between rs3212227 and MS in all study subjects in dominant (OR = 0.81, 95% CI: 0.66-0.99, P(h) = 0.480, P(z) = 0.044) and allelic comparison (OR = 0.84, 95% CI: 0.72-0.98, P(h) = 0.967, P(z) = 0.030) models, subgroup analysis based on ethnicity did not suggest an association between rs3212227 and MS risk in Caucasians in any of the genetic models, and there was no association between rs3212227 and MS risk in an Asian group. CONCLUSIONS: The IL23R polymorphisms rs10889677, rs7517847, and the IL12B polymorphism rs3212227 are not associated with MS risk.


Assuntos
Predisposição Genética para Doença , Subunidade p40 da Interleucina-12/genética , Esclerose Múltipla/genética , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina/genética , Alelos , Frequência do Gene , Estudos de Associação Genética , Humanos
16.
Am J Hum Genet ; 91(6): 1088-94, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23141294

RESUMO

Charcot-Marie-Tooth (CMT) disease represents a clinically and genetically heterogeneous group of inherited neuropathies. Here, we report a five-generation family of eight affected individuals with CMT disease type 2, CMT2. Genome-wide linkage analysis showed that the disease phenotype is closely linked to chromosomal region 10p13-14, which spans 5.41 Mb between D10S585 and D10S1477. DNA-sequencing analysis revealed a nonsense mutation, c.1455T>G (p.Tyr485(∗)), in exon 8 of dehydrogenase E1 and transketolase domain-containing 1 (DHTKD1) in all eight affected individuals, but not in other unaffected individuals in this family or in 250 unrelated normal persons. DHTKD1 mRNA expression levels in peripheral blood of affected persons were observed to be half of those in unaffected individuals. In vitro studies have shown that, compared to wild-type mRNA and DHTKD1, mutant mRNA and truncated DHTKD1 are significantly decreased by rapid mRNA decay in transfected cells. Inhibition of nonsense-mediated mRNA decay by UPF1 silencing effectively rescued the decreased levels of mutant mRNA and protein. More importantly, DHTKD1 silencing was found to lead to impaired energy production, evidenced by decreased ATP, total NAD(+) and NADH, and NADH levels. In conclusion, our data demonstrate that the heterozygous nonsense mutation in DHTKD1 is one of CMT2-causative genetic alterations, implicating an important role for DHTKD1 in mitochondrial energy production and neurological development.


Assuntos
Povo Asiático/genética , Doença de Charcot-Marie-Tooth/genética , Códon sem Sentido , Cetona Oxirredutases/genética , Sequência de Aminoácidos , Sequência de Bases , Doença de Charcot-Marie-Tooth/diagnóstico , Doença de Charcot-Marie-Tooth/metabolismo , China , Éxons , Feminino , Ordem dos Genes , Humanos , Complexo Cetoglutarato Desidrogenase , Masculino , Mitocôndrias Musculares/genética , Mitocôndrias Musculares/metabolismo , Mitocôndrias Musculares/ultraestrutura , Modelos Moleculares , Dados de Sequência Molecular , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Degradação do RNAm Mediada por Códon sem Sentido , Linhagem
17.
Acta Biochim Biophys Sin (Shanghai) ; 47(6): 466-73, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25921412

RESUMO

Transgenic mouse model with fluorescently labeled sperm has extensive application value. It is an auxiliary tool for investigating the mechanism of fertilization, especially for visualizing the oviduct-migrating ability of sperm in vivo. Here, we produced transgenic mouse lines whose sperm were tagged with enhanced green fluorescent protein (EGFP) according to the previously described method. Polymerase chain reaction analysis of tail-tip genomic DNA identified 13 founders, of which 5 male founders produced offspring to form transgenic lines. We showed that EGFP was testis-specifically expressed, sharing similar expression pattern with endogenous acrosin. It has luminal side restricted distribution in seminiferous tubules and acrosomal aggregation in mature sperm. In addition, interstrain hybridization obtained Prss37(-/-)EGFP(tg/+) males produced sperm with impaired oviduct-migrating ability as visualized under fluorescence microscope, compared with Prss37(+/+)EGFP(tg/+) counterparts. These results indicate that a transgenic mouse model with fluorescently labeled sperm has been successfully established and it is a useful tool for evaluating the oviduct-migrating ability of sperm.


Assuntos
Proteínas de Fluorescência Verde/genética , Oviductos/fisiologia , Espermatozoides/fisiologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transgenes
18.
Int J Toxicol ; 34(2): 204-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25568138

RESUMO

Bood POZ containing gene type 2 (BPOZ2), a Broad-Complex, Tramtrack, and Bric a brac domain containing protein, is an adaptor protein for the E3 ubiquitin ligase scaffold protein CUL3. It plays an important role in acute carbon tetrachloride (CCl4)-induced liver injury and regeneration in mice. In this study, we investigated the role of BPOZ2 in the process of liver fibrosis induced by chronic CCl4 treatment. The results indicate that BPOZ2 deficiency decreases sustained activation of hepatic stellate cells, attenuates collagen αI(I) and tissue inhibitor of matrix metalloprotease 1 expression, and decreases liver fibrosis after repeated CCl4 administration. These findings suggest BPOZ2 as a new therapeutic target for the prevention and treatment of hepatic fibrosis in chronic liver disease.


Assuntos
Tetracloreto de Carbono/toxicidade , Cirrose Hepática/induzido quimicamente , Proteínas Nucleares/deficiência , Animais , Western Blotting , Colágeno/análise , Feminino , Fígado/química , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Nucleic Acids Res ; 40(21): e166, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22879379

RESUMO

Methods for generating loss-of-function mutations, such as conventional or conditional gene knockout, are widely used in deciphering gene function in vivo. By contrast, inducible and reversible regulation of endogenous gene expression has not been well established. Using a mouse model, we demonstrate that a chimeric transcriptional repressor molecule (tTS) can reversibly inhibit the expression of an endogenous gene, Nmyc. In this system, a tetracycline response element (TRE) artificially inserted near the target gene's promoter region turns the gene on and off in a tetracycline-inducible manner. Nmyc(TRE) mice were generated by inserting a TRE into the first intron of Nmyc by the knockin technique. Nmyc(TRE) mice were crossed to tTS transgenic mice to produce Nmyc(TRE/TRE): tTS embryos. In these embryos, tTS blocked Nmyc expression, and embryonic lethality was observed at E11.5d. When the dam was exposed to drinking water containing doxycycline (dox), normal endogenous Nmyc expression was rescued, and the embryo survived to birth. This novel genetic modification strategy based on the tTS-dox system for inducible and reversible regulation of endogenous mouse genes will be a powerful tool to investigate target genes that cause embryonic lethality or other defects where reversible regulation or temporary shutdown of the target gene is needed.


Assuntos
Regulação da Expressão Gênica , Marcação de Genes/métodos , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Córtex Cerebelar/anormalidades , Córtex Cerebelar/crescimento & desenvolvimento , Córtex Cerebelar/metabolismo , Doxiciclina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Introdução de Genes , Genes Letais , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Repressoras/genética , Elementos de Resposta , Sindactilia/etiologia
20.
Int J Biol Macromol ; 265(Pt 1): 130895, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492692

RESUMO

Fruit is prone to rot and deterioration due to oxidative browning and microbial infection during storage, which can cause serious economic losses and food safety problems. It is urgent to develop a multifunctional composite coating to extend the shelf life of fruits. In this work, multifunctional quaternized chitosan nanoparticles (QCs/TA NPs) with excellent antibacterial and antioxidant properties were prepared based on electrostatic interaction using tannic acid instead of conventional cross-linking agents. Meanwhile, konjac glucomannan (KGM) with high viscosity, edible and biodegradable properties was used as a dispersant to disperse and stabilize the nanoparticles, and as a film-forming agent to form a multifunctional composite coating. The composite coating exhibited excellent oxygen and water vapor barrier properties, antioxidant, antibacterial, mechanical properties, hydrophobicity, and UV shielding properties. Surprisingly, the oxygen permeability of the K-NPs-15 composite film was as low as 1.93 × 10-13 (cm3·cm)/(cm2·s·Pa). The banana spray preservation experiments proved that the K-NPs-15 composite coating could effectively prolong the shelf life of bananas. Therefore, this study provides a new idea for designing multifunctional freshness preservation coatings, which has a broad application prospect.


Assuntos
Anti-Infecciosos , Mananas , Musa , Nanocompostos , Polifenóis , Antioxidantes/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos , Oxigênio
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