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1.
Mar Genomics ; 49: 100724, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31735579

RESUMO

The ancient origins and functional versatility of globins make them ideal subjects for studying physiological adaptation to environmental change. Our goals in this review are to describe the evolution of the vertebrate globin gene superfamily and to explore the structure/function relationships of hemoglobin, myoglobin, neuroglobin and cytoglobin in teleost fishes. We focus on the globins of Antarctic notothenioids, emphasizing their adaptive features as inferred from comparisons with human proteins. We dedicate this review to Guido di Prisco, our co-author, colleague, friend, and husband of C.V. Ever thoughtful, creative, and enthusiastic, Guido spearheaded study of the structure, function, and evolution of the hemoglobins of polar fishes - this review is testimony to his wide-ranging contributions. Throughout his career, Guido inspired younger scientists to embrace polar biological research, and he challenged researchers of all ages to explore evolutionary adaptation in the context of global climate change. Beyond his scientific contributions, we will miss his warmth, his culture, and his great intellect. Guido has left an outstanding legacy, one that will continue to inspire us and our research.


Assuntos
Adaptação Fisiológica , Evolução Molecular , Peixes/genética , Globinas/genética , Sequência de Aminoácidos , Animais , Regiões Antárticas , Citoglobina/genética , Hemoglobinas/genética , Família Multigênica , Mioglobina/genética , Neuroglobina/genética , Sintenia
2.
Genome Biol Evol ; 11(11): 3291-3308, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31687752

RESUMO

The Gasterosteidae fish family hosts several species that are important models for eco-evolutionary, genetic, and genomic research. In particular, a wealth of genetic and genomic data has been generated for the three-spined stickleback (Gasterosteus aculeatus), the "ecology's supermodel," whereas the genomic resources for the nine-spined stickleback (Pungitius pungitius) have remained relatively scarce. Here, we report a high-quality chromosome-level genome assembly of P. pungitius consisting of 5,303 contigs (N50 = 1.2 Mbp) with a total size of 521 Mbp. These contigs were mapped to 21 linkage groups using a high-density linkage map, yielding a final assembly with 98.5% BUSCO completeness. A total of 25,062 protein-coding genes were annotated, and about 23% of the assembly was found to consist of repetitive elements. A comprehensive analysis of repetitive elements uncovered centromere-specific tandem repeats and provided insights into the evolution of retrotransposons. A multigene phylogenetic analysis inferred a divergence time of about 26 million years ago (Ma) between nine- and three-spined sticklebacks, which is far older than the commonly assumed estimate of 13 Ma. Compared with the three-spined stickleback, we identified an additional duplication of several genes in the hemoglobin cluster. Sequencing data from populations adapted to different environments indicated potential copy number variations in hemoglobin genes. Furthermore, genome-wide synteny comparisons between three- and nine-spined sticklebacks identified chromosomal rearrangements underlying the karyotypic differences between the two species. The high-quality chromosome-scale assembly of the nine-spined stickleback genome obtained with long-read sequencing technology provides a crucial resource for comparative and population genomic investigations of stickleback fishes and teleosts.


Assuntos
Genoma , Perciformes/genética , Animais , Elementos de DNA Transponíveis , Evolução Molecular , Feminino , Proteínas de Peixes/genética , Hemoglobinas/genética , Masculino , Repetições de Microssatélites , Anotação de Sequência Molecular , Perciformes/classificação , Filogenia , Recombinação Genética
4.
BMC Med Genet ; 20(1): 136, 2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31399060

RESUMO

BACKGROUND: Thalassemia is the most common inherited disease in the world, involving α- or ß-globin in red blood cells. Thalassemia cases rank fifth in the list of national catastrophic diseases in Indonesia; however, nationwide screening for thalassemia carriers is not yet mandatory. This study aimed to assess whether blood count metrics, such as the Shine & Lal index (SLI; MCV*MCV*MCH/100), might serve as a predictor to screen thalassemia carriers in a limited resource area where molecular methods are not readily available. METHODS: During a family gathering of thalassemia patients, family members (n196) underwent a complete blood count test. Those with MCV < 80 fL and/or MCH < 27 pg and/or SLI < 1530 were further examined for Hb analysis. Only samples with HbA2 fraction > 4% or with a peak in the HbE fraction were sequenced to confirm ß-globin gene mutations. RESULTS: Of 196 family members, 117 (59.6%) had low MCV and/or low MCH and/or low SLI. The HbE fraction (mean 24.06% ± 0.95, range 22.4-26.5) was found in 27 (13.7%) cases, and all had a mutation at codon (CD)26 (c.79G > A). The mean HbA2 fraction in these samples was 3.18% ± 0.62 (range 2.6-3.8). For samples with HbA2 > 4% (n30; 15.3%), all had mutations at IVS1nt5 (c.92 + 5 G > C; n28), CD8/9 (c.27_28insG; n1) and CD19 (c.59A > G; n1). The mean HbA2 fraction with a mutation at IVS1nt5 (c.92 + 5 G > C) was 4.65% ± 0.77 (range 4.0-5.6). Interestingly, anaemia was only present in 25 and 57% of ß-thalassemia carriers with mutations at CD26 (c.79G > A) and at IVS1nt5 (c.92 + 5 G > C), respectively. CONCLUSIONS: The Shine & Lal index is helpful in the early screening of ß-thalassemia carriers, since this index confirms mutations at CD-26 (c.79G > A) and at IVS1nt5 (c.92 + 5 G > C), which are both common mutations in Bandung, Indonesia. Further DNA analysis is a topic of interest to map variants in globin genes and their distribution across populations.


Assuntos
Diagnóstico Precoce , Estudos de Associação Genética , Predisposição Genética para Doença/genética , Globinas beta/genética , Talassemia beta/genética , Adolescente , Sequência de Bases , Eritrócitos , Feminino , Hemoglobinas/genética , Humanos , Indonésia , Masculino , Deleção de Sequência
5.
Hemoglobin ; 43(1): 60-62, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31092072

RESUMO

Unstable hemoglobin (Hb) variants are a rare etiology of congenital jaundice caused by hemolytic anemia. For infant patients with jaundice this disorder is often under diagnosed or the last consideration. We report a 14-month-old boy, who presented with a long-standing jaundice. His diagnosis of Hb Sabine [ß91(F7)Leu→Pro; HBB: c.275T > C] was not revealed until gene sequencing of the ß-globin gene was performed.


Assuntos
Predisposição Genética para Doença , Variação Genética , Hemoglobinas/genética , Icterícia/genética , Icterícia/metabolismo , Alelos , Substituição de Aminoácidos , Biomarcadores , Análise Mutacional de DNA , Índices de Eritrócitos , Estudos de Associação Genética , Hemoglobinas/metabolismo , Hemoglobinas Anormais/genética , Humanos , Lactente , Icterícia/diagnóstico , Masculino , Mutação , Estabilidade Proteica , Globinas beta/genética
6.
Methods Cell Biol ; 151: 43-45, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30948023

RESUMO

A retrospective of an academic career. The article poses the question about the values involved in a life in the academy, starting with the role of hemoglobin in the chick embryo and ending with the role of calcium in the sea urchin spine.


Assuntos
Biologia Celular/história , Desenvolvimento Embrionário/genética , Mesoderma/crescimento & desenvolvimento , Ouriços-do-Mar/crescimento & desenvolvimento , Animais , Cálcio/metabolismo , Embrião de Galinha , Embrião não Mamífero , Hemoglobinas/genética , Hemoglobinas/metabolismo , História do Século XX , História do Século XXI , Ouriços-do-Mar/genética
7.
BMC Immunol ; 20(1): 12, 2019 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-31029083

RESUMO

BACKGROUND: High Immunoglobulin G (IgG) response to Plasmodium falciparum antigens is associated with partial malaria protection in sickle hemoglobin (HbS) children. However, this response has been more studied in children with heterozygous sickle cell trait (HbAS) but little explored in those with homozygous sickle cell trait (HbSS). The current study was conducted to determine the IgG responses against specific Plasmodium falciparum antigens in children with homozygous sickle cell trait (HbSS) by comparing to those with normal hemoglobin (HbAA). METHODS: A cross sectional study was conducted between April and July 2018 in Dar es Salaam tertiary hospitals. Parents were consented for their child to give about 5 ml of venous blood. IgG concentration from the blood plasma of 220 children (110 HbAA vs. 110 HbSS) were determined using indirect Enzyme Linked Immunosorbent Assay (ELISA). Then IgG medians were compared between the groups with prism 5 software (GraphPad) using Mann Whitney U test. Where the differences in age, hemoglobin levels and body weight between the groups was analyzed using independent sample t test. Multiple linear regressions were used to control cofounding variables such as body weight, age and hemoglobin level using statistical package for social sciences software (SPSS version 23). P value <0.05 was considered statistically significant. RESULTS: The median IgG concentration to PfEBA-175, Pfg27, yPfs28C antigens were HbSS; 20.7 ng/ml (IQR; 18.1-25.6) vs. HbAA; 2.3 ng/ml (IQR; 1.21-3.04), HbSS; 2.76 ng/ml (IQR: 2.08-5.69) vs. HbAA; 1.36 ng/ml (IQR: 1.28-1.76), and HbSS; 26,592 ng/ml (IQR: 10817-41,462) vs. HbAA; 14,164 ng/ml (IQR; 3069-24,302) respectively (p < 0.0001 for all IgG). In both groups; age, body weight and hemoglobin level had no impact on the levels of IgG responses to Plasmodium falciparum antigens except for HbAA group which showed a significant increase in IgG against Pfg27 by 0.004 ng/ml with 1 g/dl increase in Hb level (p = 0.028). CONCLUSIONS: This study found significant higher levels of specific Plasmodium falciparum IgG responses in children with homozygous sickle cell trait than those with normal hemoglobin.


Assuntos
Hemoglobinas/metabolismo , Malária Falciparum/imunologia , Plasmodium falciparum/fisiologia , Traço Falciforme/imunologia , Adolescente , Anticorpos Antiprotozoários/metabolismo , Antígenos de Protozoários/imunologia , Criança , Pré-Escolar , Estudos Transversais , Resistência à Doença , Feminino , Hemoglobinas/genética , Homozigoto , Humanos , Imunidade Humoral , Imunoglobulina G/metabolismo , Malária Falciparum/epidemiologia , Masculino , Traço Falciforme/epidemiologia , Tanzânia/epidemiologia
8.
Talanta ; 199: 27-31, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952256

RESUMO

Devising a robust, efficient and cost effective hemoglobin (Hb) purification strategy is one of the key challenges in the development of Hb-based blood substitutes. The aim of this study was to use molecularly imprinted polymers (MIPs) as a novel and efficient chromatographic resin to selectively recognize and purify different Hb variants. The results showed that the Hb-MIP material developed here could selectively recognize and purify various Hb directly from either crude E. coli extracts or human body fluids, such as blood plasma and cerebrospinal fluid (CSF), in one-step. The dynamic binding capacity at 10% breakthrough was around 7.4 mg mL-1resin for adult Hb (HbA) and fetal Hb (HbF). This chromatographic material also allowed identification of changes related to amino acid substitutions on the Hb protein surface. For instance, when an additional lysine residue was introduced, the HbA αY42K mutant eluted later in an Hb-MIP column than wildtype HbA. Additional negative charges on the protein surface, such as aspartate, mitigated the interaction between the protein and imprinted polymers, and therefore an αA19D-αA12D HbF mutant eluted earlier, at -2.7 column volumes compared to wildtype HbF.


Assuntos
Líquidos Corporais/química , Hemoglobinas/química , Hemoglobinas/isolamento & purificação , Impressão Molecular , Polímeros/química , Cromatografia , Escherichia coli/química , Escherichia coli/citologia , Hemoglobinas/genética , Humanos , Mutação , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
10.
Ann Lab Med ; 39(3): 237-244, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30623615

RESUMO

BACKGROUND: Type II diabetes mellitus causes many complications, and its prevalence continues to increase in Korea. Accurate measurement of glycated Hb (HbA1c) is important because of its usefulness in diagnosis, follow-up, and prediction of prognosis. We tested the analytical performance of the HLC-723 G11 Variant Mode (G11vr; Tosoh Bioscience, Inc., Tokyo, Japan), recently introduced to Korea, in detecting HbA1c. METHODS: We evaluated precision, linearity, carry-over, and turnaround time. Using 208 samples, including 108 flagged samples, we compared HbA1c concentrations from four analyzers through correlation analysis: G11vr, HLC-723 G8 Variant Mode (G8vr, Tosoh Bioscience), HLC-723 G11 Standard Mode (G11st, Tosoh Bioscience), and HLC-723 G8 Standard Mode (G8st, Tosoh Bioscience). We used HPLC mass spectrometry (MS) and capillary electrophoresis (CE) to confirm the HbA1c concentrations of 15 additional known Hb variant samples. RESULTS: Repeatability (% CV) in measuring low- and high-concentration controls was 0.57% and 0.35%, respectively; within-laboratory precision was 0.86% and 0.69%, respectively. In a linearity test, the coefficient of determination was 0.9999 (measurement range: 3.64% to 18.59%) for HbA1c. The correlations between G11vr and other analyzers were weaker for flagged samples than for non-flagged samples. The carry-over effect was less than 0.4%. Turnaround time for a single sample was lower in G11vr (one minute) than in G8vr (1.6 minutes). For 15 samples with Hb variants, G11vr HbA1c results were more similar than those of other analyzers to HPLC-MS and CE results. CONCLUSIONS: G11vr showed adequate performance and rapid turnaround time in measuring HbA1c.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Diabetes Mellitus Tipo 2/diagnóstico , Hemoglobina A Glicada/análise , Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Variação Genética , Hemoglobinas/genética , Humanos , Espectrometria de Massas/instrumentação , Reprodutibilidade dos Testes
11.
Fish Physiol Biochem ; 45(3): 943-954, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30627834

RESUMO

Teleost haemoglobins vary in polymorphisms and primary structure, although display similar functional properties. Key amino acids for Root effect (a reduction in oxygen-carrying capacity and loss of cooperativity with declining pH) are conserved throughout fish evolution. For the first time, we cloned and characterised Sparus aurata L. embryonic globin chains (eα1, eα2, eß). We also studied haemoglobins (eHbI, eHbII) behaviour in normal and low-oxygen conditions. Several amino acids in fry globins are different in chemical type (e.g. polar → non-polar and vice versa), compared to adult globins. His55α1, crucial for Root effect, is substituted by Ala in fry, presumably enhancing oxygen capture, transport and reducing the dependence of Root effect from pH. Phylogenetic trees demonstrate that eα1 globin diversified more recently than eα2; moreover, eα1, eα2 and eß globins evolved earlier than adult α and ß globins. In low-oxygen conditions, fry haemoglobins display the same behaviour of the adult haemoglobins (probably, embryonic and adult-type I Hbs display a higher oxygen affinity than type II Hbs, operating through a rapid cycle of heme-Fe auto-oxidation/reduction). Therefore, based on our results and on the comparison with adult haemoglobins, we hypothesise that embryonic haemoglobins have evolved to better adapt fry to variable habitats. We studied Sparus aurata for its economical relevance in Mediterranean aquaculture. The information we provide can help understand Sparus aurata behaviour in the wild and in rearing conditions. Further studies with functional assays will deepen the knowledge on the molecular mechanisms of fry haemoglobin physiology.


Assuntos
Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Hemoglobinas/metabolismo , Oxigênio/metabolismo , Dourada/embriologia , Sequência de Aminoácidos , Animais , Evolução Biológica , Proteínas de Peixes , Hemoglobinas/genética , Hipóxia , Dourada/metabolismo
12.
Blood Rev ; 33: 11-23, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30616747

RESUMO

Genetic lesions of the ß-globin gene result in haemoglobinopathies such as ß-thalassemia and sickle cell disease. To discover and test new molecular medicines for ß-haemoglobinopathies, cell-based and animal models are now being widely utilised. However, multiple in vitro and in vivo models are required due to the complex structure and regulatory mechanisms of the human globin gene locus, subtle species-specific differences in blood cell development, and the influence of epigenetic factors. Advances in genome sequencing, gene editing, and precision medicine have enabled the first generation of molecular therapies aimed at reactivating, repairing, or replacing silenced or damaged globin genes. Here we compare and contrast current animal and cell-based models, highlighting their complementary strengths, reflecting on how they have informed the scope and direction of the field, and describing some of the novel molecular and precision medicines currently under development or in clinical trial.


Assuntos
Regulação da Expressão Gênica , Hemoglobinas/genética , Modelos Biológicos , Animais , Loci Gênicos , Hematopoese/genética , Hemoglobinopatias/sangue , Hemoglobinopatias/genética , Hemoglobinas/metabolismo , Humanos , Pesquisa Médica Translacional , alfa-Globinas/genética , Globinas beta/genética
13.
Mol Ecol Resour ; 19(1): 245-259, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30329222

RESUMO

Combining high-throughput sequencing with targeted sequence capture has become an attractive tool to study specific genomic regions of interest. Most studies have so far focused on the exome using short-read technology. These approaches are not designed to capture intergenic regions needed to reconstruct genomic organization, including regulatory regions and gene synteny. Here, we demonstrate the power of combining targeted sequence capture with long-read sequencing technology for comparative genomic analyses of the haemoglobin (Hb) gene clusters across eight species separated by up to 70 million years. Guided by the reference genome assembly of the Atlantic cod (Gadus morhua) together with genome information from draft assemblies of selected codfishes, we designed probes covering the two Hb gene clusters. Use of custom-made barcodes combined with PacBio RSII sequencing led to highly continuous assemblies of the LA (~100 kb) and MN (~200 kb) clusters, which include syntenic regions of coding and intergenic sequences. Our results revealed an overall conserved genomic organization of the Hb genes within this lineage, yet with several, lineage-specific gene duplications. Moreover, for some of the species examined, we identified amino acid substitutions at two sites in the Hbb1 gene as well as length polymorphisms in its regulatory region, which has previously been linked to temperature adaptation in Atlantic cod populations. This study highlights the use of targeted long-read capture as a versatile approach for comparative genomic studies by generation of a cross-species genomic resource elucidating the evolutionary history of the Hb gene family across the highly divergent group of codfishes.


Assuntos
Gadiformes/classificação , Gadiformes/genética , Loci Gênicos , Genômica/métodos , Hemoglobinas/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Família Multigênica , Animais , Biologia Computacional , Evolução Molecular , Gadus morhua , Ordem dos Genes , Variação Genética , Sintenia
14.
Blood Cells Mol Dis ; 74: 13-17, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30309760

RESUMO

INTRODUCTION: Identification of beta-thalassemia carrier in prenatal screening relies on the elevated Hb A2 level. Borderline Hb A2 levels pose a diagnostic challenge. We determined the HBB genotypes in subjects with borderline Hb A2 in northern Thailand and studied the effects of coinherited alpha0-thalassemia on Hb A2 levels. METHODS: Blood samples with Hb A2 3.1-10.0% from 2193 samples submitted for prenatal thalassemia screening were selected. Information on HBB genotypes and coinherited alpha0-thalassemia were collected. All samples with unknown HBB genotypes underwent an automated DNA sequencing. The Hb A2 levels were compared according to the coinherited alpha0-thalassemia. RESULTS: HBB mutations were found in 298 (98.7%) of 302 samples with Hb A2 4.0-10.0%. In the 106 samples with Hb A2 3.1-3.9%, six had HBB mutations; four Hb Dhonburi [codon 126 (T > G)], one CAP site mutation [CAP + 1 (A > C)] and one beta0-thalassemia [codon 41/42 (-TTCT)] with a coinherited HBD mutation [nt-77 (T > C)]. The Hb A2 levels in beta-thalassemia carriers with and without coinherited alpha0-thalassemia were not significantly different. CONCLUSIONS: HBB mutations in northern Thais with borderline Hb A2 levels comprise an unstable variant Hb Dhonburi and CAP + 1 (A > C) mutation. Coinherited HBD mutation lowers Hb A2 and can cause a misidentification of a beta-thalassemia carrier.


Assuntos
Hemoglobina A2/análise , Hemoglobinas/genética , Talassemia alfa/genética , Erros de Diagnóstico , Genótipo , Hemoglobinas Anormais , Humanos , Epidemiologia Molecular , Mutação , Diagnóstico Pré-Natal , Tailândia/epidemiologia , Talassemia beta
15.
Reprod Fertil Dev ; 31(4): 724-734, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30482269

RESUMO

Haemoglobin expression is not restricted to erythroid cells. We investigated the gene expression of the haemoglobin subunits haemoglobin, alpha adult chain 1 (Hba-a1) and haemoglobin, beta (Hbb), 2,3-bisphosphoglycerate mutase (Bpgm) and the oxygen-regulated genes BCL2/adenovirus E1B interacting protein 3 (Bnip3), solute carrier family 2 (facilitated glucose transporter), member 1 (Slc2a1) and N-myc downstream regulated gene 1 (Ndrg1) in the murine preimplantation embryo, comparing invivo to invitro gene expression. Relatively high levels of Hba-a1 and Hbb were expressed invivo from the 2-cell to blastocyst stage; in contrast, little or no expression occurred invitro. We hypothesised that the presence of haemoglobin invivo creates a low oxygen environment to induce oxygen-regulated gene expression, supported by high expression of Slc2a1 and Ndrg1 in invivo relative to invitro embryos. In addition, analysis of an invitro-derived human embryo gene expression public dataset revealed low expression of haemoglobin subunit alpha (HBA) and HBB, and high expression of BPGM. To explore whether there was a developmental stage-specific effect of haemoglobin, we added exogenous haemoglobin either up to the 4-cell stage or throughout development to the blastocyst stage, but observed no difference in blastocyst rate or the inner cell mass to trophectoderm cell ratio. We conclude that haemoglobin in the invivo preimplantation embryo raises an interesting premise of potential mechanisms for oxygen regulation, which may influence oxygen-regulated gene expression.


Assuntos
Blastocisto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Hemoglobinas/metabolismo , Oxigênio/metabolismo , Animais , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário , Feminino , Hemoglobinas/genética , Camundongos
16.
Int J Lab Hematol ; 41(2): 218-226, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30489691

RESUMO

INTRODUCTION: The hemoglobinopathies pose a significant health burden in India. Apart from the ß thalassemias and sickle cell disorders, α thalassemias and structural hemoglobin variants are also common. Here we have reviewed the phenotypic and molecular diversity of hemoglobinopathies encountered at a referral center in western India over a period of 15 years. MATERIALS AND METHODS: Screening for hemoglobinopathies was done using HPLC and cellulose acetate electrophoresis. Molecular characterization was done using Covalent Reverse Dot Blot Hybridization (CRDB), Amplification Refractory Mutation System (ARMS), GAP PCR and direct DNA sequencing. RESULTS: The study includes 31 075 individuals who were referred for diagnosis of hemoglobinopathies and prenatal diagnosis. Of these 14 423 individuals showed various hemoglobin abnormalities. Beta genotyping in 5615 individuals showed the presence of 49 ß thalassemia mutations. 143 ß thalassemia heterozygotes had normal or borderline HbA2 levels. We identified three δ gene mutations (HbA2 Pellendri, HbA2 St.George, HbA2 Saurashtra) in ß thalassemia heterozygotes leading to normal HbA2 levels. The commonest defects among the raised Hb F determinants were Gγ(Αγδß)0 Indian inversion and the HPFH-3 Indian deletion. A total of 312 individuals showed the presence of α thalassemia, of which 12.0% had a single α gene deletion (-α/αα). HbH disease was identified in 29 cases with 10 different genotypes. Alpha globin gene triplication was seen in 2.1% of ß thalassemia heterozygotes with a thalassemia intermedia phenotype. Seven unusual α chain variants and eight uncommon ß chain variants were identified. CONCLUSION: The repertoire of molecular defects seen in the different globin genes will be valuable for management and control of these disorders both in India as well as in other countries where there is a huge influx of migrant populations from India.


Assuntos
Hemoglobinas/genética , Mutação , Talassemia beta/genética , Feminino , Humanos , Índia/epidemiologia , Masculino , Estudos Retrospectivos , Talassemia beta/epidemiologia
17.
Exp Hematol ; 69: 17-21.e1, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30315825

RESUMO

Transcription factor 4 (TCF4) is implicated in lymphoid cell differentiation and its expression predicts outcome in acute myeloid leukemia. Here, we investigated the role of TCF4 in myelopoiesis. Overexpression of TCF4 (TCF4OE) in umbilical cord blood (UCB) cells resulted in a twofold increase in erythroid colony forming units (CFU-Es), whereas knock-down (KD) of TCF4 (TCF4KD) caused a dramatic decrease in the number of erythroid colonies. In megakaryocyte CFUs (CFU-MKs), both TCF4KD and TCF4OE inhibited MK colony formation. TCF4 did not have an impact on granulocyte, macrophage, or granulocyte-macrophage colonies or on the proportion of MK-erythrocyte progenitors (MEPs) in culture. Because TCF4 affects erythroid/MK development and these lineages are affected in myelodysplastic syndrome (MDS), we studied the impact of TCF4 expression in this disease. MDS patients with high (≥median) TCF4 mRNA expression had higher hemoglobin (Hb) levels than MDS patients with low TCF4 expression (mean 9.0 vs. 8.55 g/dL, p = 0.02). Overall, TCF4 mRNA expression was lower in hematopoietic stem cells, common myeloid progenitors, and MEPs from MDS patients, but not in granulocyte-macrophage progenitors, compared with healthy controls. Therefore, in cell fractions with erythroid lineage potential, TCF4 is expressed less in MDS patients than in healthy controls. This correlates with the low overall Hb levels seen in MDS patients compared with healthy individuals and is consistent with the positive impact of TCF4 on erythroid development while not having impact on white colonies. These results indicate a role for TCF4 as a novel factor in erythroid-megakaryocytic differentiation.


Assuntos
Diferenciação Celular , Células Precursoras Eritroides/metabolismo , Hemoglobinas , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Mielopoese , Fator de Transcrição 4 , Células Cultivadas , Células Precursoras Eritroides/patologia , Sangue Fetal/metabolismo , Regulação da Expressão Gênica , Hemoglobinas/biossíntese , Hemoglobinas/genética , Humanos , Megacariócitos/patologia , Síndromes Mielodisplásicas/patologia , Fator de Transcrição 4/genética , Fator de Transcrição 4/metabolismo
18.
Circulation ; 139(10): 1300-1319, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30586735

RESUMO

BACKGROUND: Platelet-neutrophil interactions contribute to vascular occlusion and tissue damage in thromboinflammatory disease. Platelet glycoprotein Ibα (GPIbα), a key receptor for the cell-cell interaction, is believed to be constitutively active for ligand binding. Here, we established the role of platelet-derived protein disulfide isomerase (PDI) in reducing the allosteric disulfide bonds in GPIbα and enhancing the ligand-binding activity under thromboinflammatory conditions. METHODS: Bioinformatic analysis identified 2 potential allosteric disulfide bonds in GPIbα. Agglutination assays, flow cytometry, surface plasmon resonance analysis, a protein-protein docking model, proximity ligation assays, and mass spectrometry were used to demonstrate a direct interaction between PDI and GPIbα and to determine a role for PDI in regulating GPIbα function and platelet-neutrophil interactions. Also, real-time microscopy and animal disease models were used to study the pathophysiological role of PDI-GPIbα signaling under thromboinflammatory conditions. RESULTS: Deletion or inhibition of platelet PDI significantly reduced GPIbα-mediated platelet agglutination. Studies using PDI-null platelets and recombinant PDI or Anfibatide, a clinical-stage GPIbα inhibitor, revealed that the oxidoreductase activity of platelet surface-bound PDI was required for the ligand-binding function of GPIbα. PDI directly bound to the extracellular domain of GPIbα on the platelet surface and reduced the Cys4-Cys17 and Cys209-Cys248 disulfide bonds. Real-time microscopy with platelet-specific PDI conditional knockout and sickle cell disease mice demonstrated that PDI-regulated GPIbα function was essential for platelet-neutrophil interactions and vascular occlusion under thromboinflammatory conditions. Studies using a mouse model of ischemia/reperfusion-induced stroke indicated that PDI-GPIbα signaling played a crucial role in tissue damage. CONCLUSIONS: Our results demonstrate that PDI-facilitated cleavage of the allosteric disulfide bonds tightly regulates GPIbα function, promoting platelet-neutrophil interactions, vascular occlusion, and tissue damage under thromboinflammatory conditions.


Assuntos
Anemia Falciforme/enzimologia , Plaquetas/enzimologia , Inflamação/enzimologia , Neutrófilos/metabolismo , Adesividade Plaquetária , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Trombose/enzimologia , Anemia Falciforme/sangue , Anemia Falciforme/genética , Animais , Modelos Animais de Doenças , Hemoglobinas/genética , Hemoglobinas/metabolismo , Humanos , Inflamação/sangue , Inflamação/genética , Ligantes , Camundongos Endogâmicos C57BL , Camundongos Knockout , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Ligação Proteica , Isomerases de Dissulfetos de Proteínas/deficiência , Isomerases de Dissulfetos de Proteínas/genética , Transdução de Sinais , Trombose/sangue , Trombose/genética
19.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(5): 422-427, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31894674

RESUMO

OBJECTIVE: To investigate the effects of mitochondrial ATPase inhibitory factor 1 (Atpif1) on hemoglobin synthesis. METHODS: Firstly, the K562 cells were divided into 2 groups, hypoxia-treated group and normoxic control group. The K562 cells in hypoxia-treated group were treated with 2% oxygen. The K562 cells in the two groups were collected after cultured for 24, 48 and 72 hours. The proliferation-inhibitory rates of cells were detected by CCK-8 assay. The apoptosis rates of K562 cells were analyzed by flow cytometry. The hemoglobin synthesis of K562 cells was induced by hemin. The gene expressions of Atpif1, Aladelta-aminolevulinate synthase 2 (Alas2) and nuclear factor kappa B (NF-κB) were detected by qRT-PCR. Then, the K562 cells were cultured in hypoxic incubator and divided into blank control group, negative control group and si-Atpif1 group. After sliencing Atpif1 gene, the hemoglobin synthesis and the levels of NF-κB and Alas2 were determined. RESULTS: Compared with the normoxic control group, the proliferation activity of K562 cells was inhibited, the apoptosis rate was increased, and the hemoglobin synthesis was also increased in hypoxia-treated groups. The expressions of Atpif1, Alas2 and NF-κB mRNA of K562 cells were upregulated. Compared with blank control group and negative control group, the content of hemoglobin was decreased, and the levels of NF-κB and Alas2 mRNA were also decreased in si-Atpif1 group. CONCLUSION: Atpif1 gene is involved in the regulation of hemoglobin synthesis. Exploring its roles in the development of high altitude polycythemia (HAPC) can provide new ideas and therapeutic targets for the prevention and treatment of HAPC.


Assuntos
Hemoglobinas , Proteínas , Apoptose/genética , Proliferação de Células/genética , Regulação da Expressão Gênica/genética , Hemoglobinas/genética , Humanos , Células K562 , NF-kappa B/genética , Proteínas/genética , RNA Mensageiro/genética
20.
PLoS One ; 13(12): e0208465, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30513111

RESUMO

A methodology to cluster proteins based on their dynamics' similarity is presented. For each pair of proteins from a dataset, the structures are superimposed, and the Anisotropic Network Model modes of motions are calculated. The twelve slowest modes from each protein are matched using a local mode alignment algorithm based on the local sequence alignment algorithm of Smith-Waterman. The dynamical similarity distance matrix is calculated based on the top scoring matches of each pair and the proteins are clustered using a hierarchical clustering algorithm. The utility of this method is exemplified on a dataset of protein chains from the globin family and a dataset of tetrameric hemoglobins. The results demonstrate the effect of the quaternary structure of globin members on their intrinsic dynamics and show good ability to distinguish between different states of hemoglobin, revealing the dynamical relations between them.


Assuntos
Globinas/química , Globinas/genética , Família Multigênica , Sequência de Aminoácidos , Animais , Archaea/classificação , Archaea/genética , Conjuntos de Dados como Assunto , Globinas/metabolismo , Hemoglobinas/química , Hemoglobinas/genética , Humanos , Methanosarcina/classificação , Methanosarcina/genética , Modelos Moleculares , Filogenia , Porcos-Espinhos , Conformação Proteica , Multimerização Proteica , Estrutura Quaternária de Proteína , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
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