RESUMEN
Porcine epidemic diarrhea virus (PEDV) is an entero-pathogenic coronavirus, which belongs to the genus Alphacoronavirus in the family Coronaviridae, causing lethal watery diarrhea in piglets. Previous studies have shown that PEDV has developed an antagonistic mechanism by which it evades the antiviral activities of interferon (IFN), such as the sole accessory protein open reading frame 3 (ORF3) being found to inhibit IFN-ß promoter activities, but how this mechanism used by PEDV ORF3 inhibits activation of the type I signaling pathway remains not fully understood. Thus, in this present study, we showed that PEDV ORF3 inhibited both polyinosine-polycytidylic acid (poly(I:C))- and IFNα2b-stimulated transcription of IFN-ß and interferon-stimulated genes (ISGs) mRNAs. The expression levels of antiviral proteins in the retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs)-mediated pathway was down-regulated in cells with over-expression of PEDV ORF3 protein, but global protein translation remained unchanged and the association of ORF3 with RLRs-related antiviral proteins was not detected, implying that ORF3 only specifically suppressed the expression of these signaling molecules. At the same time, we also found that the PEDV ORF3 protein inhibited interferon regulatory factor 3 (IRF3) phosphorylation and poly(I:C)-induced nuclear translocation of IRF3, which further supported the evidence that type I IFN production was abrogated by PEDV ORF3 through interfering with RLRs signaling. Furthermore, PEDV ORF3 counteracted transcription of IFN-ß and ISGs mRNAs, which were triggered by over-expression of signal proteins in the RLRs-mediated pathway. However, to our surprise, PEDV ORF3 initially induced, but subsequently reduced the transcription of IFN-ß and ISGs mRNAs to normal levels. Additionally, mRNA transcriptional levels of signaling molecules located at IFN-ß upstream were not inhibited, but elevated by PEDV ORF3 protein. Collectively, these results demonstrate that inhibition of type I interferon signaling by PEDV ORF3 can be realized through down-regulating the expression of signal molecules in the RLRs-mediated pathway, but not via inhibiting their mRNAs transcription. This study points to a new mechanism evolved by PEDV through blockage of the RLRs-mediated pathway by ORF3 protein to circumvent the host's antiviral immunity.
Asunto(s)
Infecciones por Coronavirus , Interferón Tipo I , Virus de la Diarrea Epidémica Porcina , Enfermedades de los Porcinos , Animales , Porcinos , Virus de la Diarrea Epidémica Porcina/genética , Sistemas de Lectura Abierta , Transducción de Señal , Antivirales , Infecciones por Coronavirus/veterinaria , Interferón Tipo I/metabolismoRESUMEN
Porcine epidemic diarrhea virus (PEDV) envelope protein (E) is recognized as a viroporin that plays important functions in virus budding, assembly and virulence. Our previous study found that PEDV E protein induces endoplasmic reticulum stress (ERS), as well as suppresses the type I interferon (IFN) response, but their link and underlying mechanism remain obscure. To better understand this relationship, we investigated the roles of PEDV E protein-induced ERS in regulating cellular type I IFN production. Our results showed that PEDV E protein localized in the ER and triggered ERS through activation of PERK/eIF2α branch, as revealed by the up-regulated phosphorylation of PERK and eIF2α. PEDV E protein also significantly inhibited both poly(I:C)-induced and RIG-I signaling-mediated type I interferon production. The PERK/eIF2α branch of ERS activated by PEDV E protein led to the translation attenuation of RIG-I signaling-associated antiviral proteins, resulting in the suppression of type I IFN production. However, PEDV E protein had no effect on the mRNA transcription of RIG-I-associated molecules. Moreover, suppression of ERS with 4-PBA, a widely used ERS inhibitor, restored the expression of RIG-I-signaling-associated antiviral proteins and mRNA transcription of IFN-ß and ISGs genes to their normal levels, suggesting that PEDV E protein blocks the production of type I IFN through inhibiting expression of antiviral proteins caused by ERS-mediated translation attenuation. This study elucidates the mechanism by which PEDV E protein specifically modulates the ERS to inhibit type I IFN production, which will augment our understanding of PEDV E protein-mediated virus evasion of host innate immunity.
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Infecciones por Coronavirus , Interferón Tipo I , Virus de la Diarrea Epidémica Porcina , Enfermedades de los Porcinos , Porcinos , Animales , Antivirales , Estrés del Retículo Endoplásmico , Línea Celular , Factor 2 Eucariótico de Iniciación , ARN Mensajero , Infecciones por Coronavirus/veterinariaRESUMEN
The unique structures of polynuclear MoxSy clusters make it possible to maximize the number of their active sites and for them to be good candidates for HER catalysts. An appropriate support is highly necessary not only to avoid the desorption of MoxSy clusters in a working environment, but also to improve their HER activity. Our work here shows that the CeO2 support could provide strong support for interaction with various MoxSy clusters and the formed MoxSy/CeO2 hetero-structures also have modest ΔGH* for the HER. The electronic features of MoxSy clusters are regulated by the CeO2 support, which leads to charge redistribution on edge atoms and plays a key role in H adsorption. Our studies provide instructive predictions on efficient candidates of molybdenum-sulfur based catalysts for the HER.
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BACKGROUND: Mutations in bone morphogenetic protein type II receptor (BMPR2) have been found in patients with congenital heart disease-associated pulmonary arterial hypertension (CHD-PAH). Our study aimed to clarify whether deficient BMPR2 signalling acts through downstream effectors, inhibitors of DNA-binding proteins (IDs) during heart development to contribute to the progress of PAH in CHD patients. METHODS: To confirm that IDs are downstream effectors of BMPR2 signalling in cardiac mesoderm progenitors (CMPs) and contribute to PAH, we generated cardiomyocyte-specific Id 1/3 knockout mice (Ids cDKO), and 12 out of 25 developed mild PAH with altered haemodynamic indices and pulmonary vascular remodelling. Moreover, we generated ID1 and ID3 double-knockout (IDs KO) human embryonic stem cells that recapitulated the BMPR2 signalling deficiency of CHD-PAH induced pluripotent stem cells (iPSCs). RESULTS: Cardiomyocytes differentiated from iPSCs derived from CHD-PAH patients with BMP receptor mutations exhibited dysfunctional cardiac differentiation and reduced calcium (Ca2+) transients, as evidenced by confocal microscopy experiments. Smad1/5 phosphorylation and ID1 and ID3 expression were reduced in CHD-PAH iPSCs and in Bmpr2 +/- rat right ventricles. Moreover, ultrasound revealed that 33% of Ids cDKO mice had detectable defects in their ventricular septum and pulmonary regurgitation. Cardiomyocytes isolated from mouse right ventricles also showed reduced Ca2+ transients and shortened sarcomeres. Single-cell RNA sequencing analysis revealed impaired differentiation of CMPs and downregulated USP9X expression in IDs KO cells compared with wild-type cells. CONCLUSION: We found that BMPR2 signals through IDs and USP9X to regulate cardiac differentiation, and the loss of ID1 and ID3 expression contributes to cardiomyocyte dysfunction in CHD-PAH patients with BMPR2 mutations.
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Cardiopatías Congénitas , Hipertensión Pulmonar , Hipertensión Arterial Pulmonar , Animales , Receptores de Proteínas Morfogenéticas Óseas de Tipo II/genética , Receptores de Proteínas Morfogenéticas Óseas de Tipo II/metabolismo , Proteínas de Unión al ADN/metabolismo , Cardiopatías Congénitas/genética , Ratones , Mutación , Arteria Pulmonar , Ratas , Análisis de Secuencia de ARN , Función Ventricular DerechaRESUMEN
Primary cytoreductive surgery with platinum-taxane-based chemotherapy is the standard treatment for ovarian cancer (OC) patients; however, resistance to chemotherapy is a contributing factor to OC mortality. Paclitaxel (PTX), the most widely used taxane, has become the first-line drug against OC. The molecular mechanism of PTX resistance is different from that of platinum-based agents and is still not completely elucidated. Our previous study showed that glucose-regulated protein 78 (GRP78) is involved in the resistance of OC cells to PTX. However, little is known regarding endogenous inhibitors of this gene. MicroRNAs (miRNAs) play critical roles in the regulation of gene expression; therefore, we sought to identify miRNA(s) with potential to target GRP78 under the hypothesis that miRNA(s) could serve as potential therapeutic targets. Here, we show that miR-181c, predicted to target GRP78, was downregulated in PTX-resistant OC cells and tissues. MiR-181c downregulated GRP78 expression and induced apoptosis by directly targeting its 3'-untranslated region (UTR). Overexpression of miR-181c sensitized resistant OC to PTX by inhibiting the PI3K/Akt pathway in vitro and in vivo. Taken together, our findings indicate that the delivery of miR-181c can efficiently suppress GRP78 expression and GRP78-mediated PTX resistance in OC and suggest that this strategy has therapeutic potential.
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MicroARNs , Neoplasias Ováricas , Regiones no Traducidas 3' , Carcinoma Epitelial de Ovario/genética , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Chaperón BiP del Retículo Endoplásmico/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
As a novel anodic electrode for Li-ion storage, the cubic Bi4Ge3O12 phase can experimentally deliver a remarkably high reversible specific capacity of 586 mA h g-1 at 200 mA h g-1 with a coulombic efficiency of 99.8% after 500 cycles, and has recently attracted attention for its stable electrochemical performance. Here we calculated its lithiation/delithiation reactions by using density functional theory studies, through the structural changes as the conversion and alloying reaction takes place during the Li-ion insertion and extraction process. The obtained theoretical capacity of Li is 48.75 mol (â¼1043 mA h g-1) for 1 mol Bi4Ge3O12. The decomposed Bi2O3 (P3[combining macron]m1) and GeO2 (P3121) in the lithiation process of Bi4Ge3O12 are the active materials to react with the Li atoms via a conversion reaction. Besides Li2O with both Fm3[combining macron]m and Pnma phases, the final lithiation products of Bi4Ge3O12 should include Li3Bi (Fm3[combining macron]m) and Li4.25Ge (F4[combining macron]3m), through the alloying reactions of multi-valence elements of Bi and Ge with Li. Bi and Ge metals are also helpful in the decomposition of Li2O into Li during the delithiation process, increasing the reversibility of the conversion reactions. Our research provides theoretical support to understand the working mechanism of Bi4Ge3O12 and related mixed-metal anode materials.
RESUMEN
FGF-2 accumulates in many tumor tissues and is closely related to the development of tumor angiogenesis and the immunosuppressive microenvironment. This study aimed to investigate whether active immunization against FGF-2 could modify antitumor immunity and enhance the efficacy of an HPV16 E7-specific therapeutic vaccine. Combined immunization targeting both FGF-2 and E7 significantly suppressed tumor growth, which was accompanied by significantly increased levels of IFN-γ-expressing splenocytes and effector CD8 T cells and decreased levels of immunosuppressive cells such as regulatory T cells (Tregs) and myeloid-derived suppressor cells(MDSCs) in both the spleen and tumor; in addition, the levels of FGF-2 and neovascularization in tumors were decreased in the mice receiving the combined immunization, and tumor cell apoptosis was promoted. The combination of an HPV16 E7-specific vaccine and active immunization against FGF-2 significantly enhances antitumor immune responses in mice with TC-1 tumors, indicating a promising strategy for tumor immunotherapy.
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Vacunas contra el Cáncer/farmacología , Factor 2 de Crecimiento de Fibroblastos/inmunología , Neovascularización Patológica/inmunología , Proteínas E7 de Papillomavirus/inmunología , Vacunas contra Papillomavirus/farmacología , Animales , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/inmunología , Línea Celular Tumoral , Factor 2 de Crecimiento de Fibroblastos/antagonistas & inhibidores , Factor 2 de Crecimiento de Fibroblastos/genética , Humanos , Inmunoterapia , Ratones , Neovascularización Patológica/genética , Neovascularización Patológica/prevención & control , Neovascularización Patológica/virología , Proteínas E7 de Papillomavirus/antagonistas & inhibidores , Proteínas E7 de Papillomavirus/genética , Vacunas contra Papillomavirus/inmunología , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , VacunaciónRESUMEN
As an alternative for depleting fossil fuel energy, hydrogen economy desires low-cost and efficient hydrogen production from water splitting. In order to explore a cheap, abundant, active, and durable catalyst for the electrocatalytic hydrogen evolution reaction (HER), two-dimensional (2D) ceria nanosheets are produced through a thermal decomposition exfoliation method from CeCO3OH with a layer-stacked structure. The additional cobalt dopant promotes formation of oxygen vacancies in ceria nanosheets and, in turn, optimizes hydrogen binding/water dissociation and increases the active sites. As a result, the 2D Co-doped CeO2 nanosheets exhibit an excellent catalytic performance in alkaline HER such that the overpotential is as low as 132 and 215 mV to deliver a high current density of 100 and 500 mA cm-2, respectively, outperforming Pt. Such 2D Co-doped CeO2 nanosheets are also durable HER electrocatalysts, as the activity loss during an extended period of operation is nearly negligible.
RESUMEN
Recently, interleukin (IL)-33 has been closely associated with a variety of clinical cancers. IL-33 presents both protumorigenic, and less frequently, antitumorigenic functions depending on disease conditions. IL-33 signaling appears to be a possible target for the treatment of applicable tumor diseases. This study aimed to develop an effective approach to intervene in IL-33 functioning in tumors and reveal the immunotherapeutic potential of anti-IL-33 active immunization. Recombinant truncated hepatitis B virus core antigen (HBcAg), presenting mature IL-33 molecules on the surface of virus-like particles (VLPs), was prepared and used to immunize BALB/c mice in a model of murine 4T1 breast cancer. The immunization was performed through either a preventive or therapeutic strategy in two separate studies. Anti-IL-33 immunization with VLPs elicited a persistent and highly titrated specific antibody response and significantly suppressed orthotopic tumor growth in the preventive study and lung metastasis in both studies. The underlying mechanisms might include promoting tumor-specific Th1 and CTL-mediated cellular responses and the expression of the effector molecule interferon-γ (IFN-γ), suppressing T-helper type 2 (Th2) responses, and significantly reducing the infiltration of immunosuppressive Treg (regulatory T) cells and myeloid-derived suppressor cells (MDSCs) into tumor tissues in the immunized mice. In conclusion, anti-IL-33 active immunization employing recombinant VLPs as an antigen delivery platform effectively modified the tumor microenvironment and promoted antitumor immunity, indicating the potential of this approach as a new and promising immunotherapeutic strategy for the treatment of cancers where IL-33 plays a definite protumorigenic role. STATEMENT OF SIGNIFICANCE: Interleukin (IL)-33 is closely associated with a variety of clinical cancers. IL-33 signaling appears to be a possible target for the treatment of applicable tumor diseases. Recombinant truncated hepatitis B virus core antigen (HBcAg), presenting mature IL-33 molecules on the surface of virus-like particles (VLPs), was prepared and used to immunize BALB/c mice in a model of murine 4T1 breast cancer. The immunization was performed through either a preventive or therapeutic strategy in two separate studies. Anti-IL-33 immunization with VLPs elicited a persistent and highly titrated specific antibody response and significantly suppressed orthotopic tumor growth and lung metastasis in both studies. Furthermore, anti-IL-33 active immunization employing recombinant VLPs as an antigen delivery platform effectively modified the tumor microenvironment and promoted antitumor immunity, indicating its potential as a new and promising immunotherapeutic strategy for the treatment of cancers where IL-33 plays a definite protumorigenic role.
Asunto(s)
Inmunidad , Interleucina-33/metabolismo , Neoplasias Mamarias Animales/inmunología , Modelos Biológicos , Recombinación Genética/genética , Microambiente Tumoral , Virión/metabolismo , Animales , Línea Celular Tumoral , Femenino , Antígenos del Núcleo de la Hepatitis B/inmunología , Inmunización , Neoplasias Pulmonares/secundario , Neoplasias Mamarias Animales/patología , Ratones Endogámicos BALB C , Células Supresoras de Origen Mieloide/inmunología , Linfocitos T Reguladores/inmunología , Células TH1/inmunologíaRESUMEN
FDA approval of CpG oligodeoxynucleotide (CpG ODN) adjuvants for a human hepatitis B virus vaccine has been delayed until late 2017 because of concerns regarding the severe side effects, which may be attributed to the high dosage and systemic diffusion of this proinflammatory material. Considering that PLGA could provide shelter to resist nucleases in tissue and that cationic lipids could confine anionic oligonucleotides in the nanoparticles via electrostatic attraction to avoid systemic diffusion, we encapsulated a natural phosphodiester or the expensive phosphorothioate CpG ODNs in our previously reported hyaluronic acid-modified cationic lipid-PLGA hybrid nanoparticles and evaluated vaccine efficacy in a TC-1-grafted mouse model. Our results showed that together with Poly I:C, CpG ODN could promote the maturation of bone marrow-derived dendritic cells and the cross-presentation of exogenous antigens in vitro. For the coencapsulation with Poly I:C, in vivo studies showed that adjuvant effects on the vaccine efficacy of tumor depression, immune cell activation, and memory T-cell elevation of phosphodiester CpG ODNs were comparable to those of the phosphorothioate CpG ODNs at a low concentration (5⯵g/dose). In conclusion, the combination of oligonucleotide adjuvants and synthetic particulate systems not only potentiated the immunogenicity of these nanoparticles but also made these adjuvants safer and more economical, which may be helpful for their wide application.
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Adyuvantes Inmunológicos/administración & dosificación , Nanopartículas , Oligodesoxirribonucleótidos/administración & dosificación , Poli I-C/administración & dosificación , Vacunas/administración & dosificación , Adyuvantes Inmunológicos/toxicidad , Animales , Cationes , Células Dendríticas/inmunología , Femenino , Ácido Hialurónico/química , Lípidos/química , Ratones , Ratones Endogámicos C57BL , Neoplasias Experimentales/inmunología , Oligodesoxirribonucleótidos/inmunología , Oligodesoxirribonucleótidos/toxicidad , Poli I-C/inmunología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Linfocitos T/inmunología , Vacunas/inmunología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Although the antimicrobial peptide cathelicidin-BF shows minimal cytotoxicity in mammalian cells and has excellent direct killing effects on multidrug-resistant clinical pathogens such as Pseudomonas aeruginosa, its clinical application is precluded by its high sensitivity to serum proteases. Here, we demonstrate that intravenous administration of cathelicidin-BF after P. aeruginosa infection did not increase the survival rate of mice with acute pneumonia but that pretreatment with cathelicidin-BF ameliorated pneumonia by effectively activating innate immunity. Enhanced neutrophil extracellular trap (NET) activation and release (NETosis) are key processes for capturing and killing bacteria, concomitantly enhanced macrophage clearance activity, including phagocytosis and autophagy, may eliminate NETs early enough to prevent severe tissue damage. Our study not only suggests a possible approach for applying cathelicidin-BF in vivo but also provides a possible defense strategy against multidrug-resistant pathogens, i.e., efficiently activation of innate immunity.
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Catelicidinas/uso terapéutico , Trampas Extracelulares/fisiología , Macrófagos/fisiología , Neutrófilos/fisiología , Neumonía/tratamiento farmacológico , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa/fisiología , Animales , Autofagia , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunidad Innata , Ratones , Ratones Endogámicos BALB C , Infiltración Neutrófila , FagocitosisRESUMEN
An unexplored promising lithiation-host anode material, Bi4Ge3O12, delivers a reversible specific discharge capacity of â¼586 mA h g-1 at 200 mA g-1 after 500 cycles with a coulombic efficiency of â¼99.8%. DFT calculations detected distorted [BiO6]9- octahedra, and the band structure of BGO revealed an indirect gap of 3.50 eV. A plausible reaction mechanism of storing lithium is proposed.
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We have systematically investigated the electronic structures and activation capacities of BiOBr {001} facets with different atomic terminations by means of DFT methods. Our calculations reveal that oxygen vacancies (OVs) give a significant boost in band edges of the O-terminated BiOBr {001} facets, and excess electrons induced by OVs could exceed the reduction potentials of high-energy N2 intermediates. Interestingly, the Bi-terminated BiOBr {001} facets may be good candidates for photocatalytic nitrogen fixation due to the stronger activation ability of N2 molecules comparing with O-terminated BiOBr {001} facets with OVs. Moreover, the Bi-terminated BiOBr {001} facets may tend to yield NH3 instead of N2 H4 .
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Cross-talk by pattern recognition receptors may facilitate the maturation of dendritic cells and fine tune the immune response. Thus, the inclusion of ligands agonistic to multiple receptors in a vaccine formula may be an effective strategy to elicit robust antitumor cellular immunity. We tested the adjuvant effects and possible synergy of CpG (CpG oligodeoxynucleotide), Poly I:C (polyinosinic-polycytidylic acid) and the cationic peptide Cramp (cathelicidin-related antimicrobial peptide) formulated in a DOTAP (1,2-dioleoyl-3-trimethylammonium-propane) liposomal HPV E7 epitope vaccine on a TC-1 grafted mouse model. The vaccine formulations were administered both preventively and therapeutically. Based on our results, both CpG and Poly I:C-adjuvanted vaccines abolished tumor development in a preventive trial and significantly suppressed tumor growth in a therapeutic trial. Increased interferon (IFN)-γ expression and potent memory T cells in splenocytes as well as elevated CD8+IFN-γ+ cells in both spleen and tumor tissue indicated an elevated E744-62-specific cellular immune response. Although synergistic effects were detected between CpG and Poly I:C, their adjuvant effects were not enhanced further when combined with Cramp. Because the enhancement of tumor antigen-specific cellular immune responses is vital for the clearance of infected and cancerous cells, our results contribute a potential adjuvant combination for cancer vaccines.
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Cationes/inmunología , Epítopos/inmunología , Oligodesoxirribonucleótidos/inmunología , Proteínas E7 de Papillomavirus/inmunología , Vacunas contra Papillomavirus/inmunología , Péptidos/inmunología , Adyuvantes Inmunológicos/farmacología , Animales , Antígenos de Neoplasias/inmunología , Vacunas contra el Cáncer/inmunología , Modelos Animales de Enfermedad , Femenino , Inmunidad Celular/inmunología , Inmunización/métodos , Ratones , Ratones Endogámicos C57BL , Poli I-C/inmunología , Linfocitos T Citotóxicos/inmunología , Vacunación/métodosRESUMEN
The genetic diversity and relationships among ethnic minority populations of southwest China were investigated using seven polymorphic restriction enzyme sites in the ß-globin gene cluster. The haplotypes of 1392 chromosomes from ten ethnic populations living in southwest China were determined. Linkage equilibrium and recombination hotspot were found between the 5' sites and 3' sites of the ß-globin gene cluster. 5' haplotypes 2 (+---), 6 (-++-+), 9 (-++++) and 3' haplotype FW3 (-+) were the predominant haplotypes. Notably, haplotype 9 frequency was significantly high in the southwest populations, indicating their difference with other Chinese. The interpopulation differentiation of southwest Chinese minority populations is less than those in populations of northern China and other continents. Phylogenetic analysis shows that populations sharing same ethnic origin or language clustered to each other, indicating current ß-globin cluster diversity in the Chinese populations reflects their ethnic origin and linguistic affiliations to a great extent. This study characterizes ß-globin gene cluster haplotypes in southwest Chinese minorities for the first time, and reveals the genetic variability and affinity of these populations using ß-globin cluster haplotype frequencies. The results suggest that ethnic origin plays an important role in shaping variations of the ß-globin gene cluster in the southwestern ethnic populations of China.
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Pueblo Asiatico/genética , Globinas beta/genética , China , Variación Genética , Genotipo , Haplotipos , Humanos , Desequilibrio de Ligamiento , Familia de Multigenes , Filogenia , Polimorfismo Genético , Globinas beta/clasificaciónRESUMEN
OBJECTIVE: To analyze the hematological and genetic characteristics of unstable hemoglobin Rush (Hb Rush) and compound heterozygote of Hb Rush and thalassemia. METHODS: Peripheral blood samples and genomic DNA from three patients (including two ethnic Dai and one Han Chinese) with anemia of undetermined origin were collected. Hematological phenotypes of these patients were determined through red blood cell analysis and hemoglobin electrophoresis. Genotypes of alpha- and beta-globin genes, -158 Xmnâ polymorphic site of Gγ promoter region, and haplotypes of 7 polymorphic restriction sites in the beta-globin gene cluster were determined using PCR-based methods and DNA sequencing. RESULTS: All patients have presented hypochromic microcytic anemia and hemoglobin fraction with significant increased measurement (30.5%-59.2%) in the region of fetal hemoglobin during alkaline medium electrophoresis. DNA analysis suggested that all patients have carried mutations leading to the unstable hemoglobin Rush (HBB codon 101, GAG>CAG, Glu>Gln). Two of them were compound heterozygotes of Hb Rush and thalassemia mutations of -α 3.7,CD17 and Hb E, respectively. Hb Rush mutation was associated with various haplotypes of the ß-globin gene cluster. No significant association was found between increased abnormal hemoglobin fraction in the region of Hb F and the polymorphism of Gγ promoter or large deletion of the beta-globin gene cluster. CONCLUSION: This study has confirmed the distribution of Hb Rush among various Chinese populations and is the third report of its kind. Hb Rush can result in increased measurement of hemoglobin fraction in the region of fetal hemoglobin (Hb F) during routine hemoglobin electrophoresis under alkaline condition. Hb Rush heterozygote alone can lead to hypochromic microcytic anemia and thalassemia-like phenotype. Prenatal diagnosis of Hb Rush is necessary for carriers.
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Hemoglobinas Anormales/genética , Mutación , Polimorfismo Genético , Talasemia/genética , Adulto , Secuencia de Bases , Electroforesis de las Proteínas Sanguíneas/métodos , Femenino , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Genotipo , Haplotipos , Hemoglobinas Anormales/metabolismo , Heterocigoto , Humanos , Lactante , Fenotipo , Análisis de Secuencia de ADN/métodos , Talasemia/sangre , Talasemia/diagnóstico , Adulto Joven , Globinas alfa/genética , Globinas alfa/metabolismo , Globinas beta/genética , Globinas beta/metabolismoRESUMEN
OBJECTIVE: The aim of this study was to determine the distribution and origin of hemoglobin E (HbE) in seven minority groups from various geographical regions of the malaria-endemic Yunnan province, southwestern China, which have similar ethnic origins and geographic relationships with HbE-prevalent populations of Southeast Asian countries. METHODS: By using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) methods, the prevalence of HbE was examined in 1488 individuals from seven native minority groups of Yunnan, and ß-globin gene cluster haplotypes were determined on 1420 chromosomes. RESULTS: The prevalence of HbE in the study populations ranged from 1.5 to 39.1%. Higher HbE prevalence was correlated with the minority groups of Tibeto-Burman origin and groups from the Dehong district. The ßE -globin genes in Yunnan were mostly associated with three haplotypes [-+++++-], [+----+-], and [-+-+++-] on chromosomes with gene framework 2. Interestingly, the predominant ßE associated haplotype in Yunnan minorities was remarkably different from that in other previously reported populations. This study, for the first time, reports population-based data on the heterogeneity of HbE gene frequencies and haplotype distribution in native minorities from southwestern China. CONCLUSIONS: Natural selection based on the presence of malaria, ethnic origin, and epistatic interactions may be factors of varying importance for the remarkable variation in HbE frequency among these minority groups. In addition, there appears to be a common origin of the ßE -globin gene in populations from Yunnan and Southeast Asia. Am. J. Hum. Biol. 28:927-931, 2016. © 2016Wiley Periodicals, Inc.