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1.
Nat Commun ; 11(1): 3569, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678083

RESUMO

The clinically important MAM blood group antigen is present on haematopoietic cells of all humans except rare MAM-negative individuals. Its molecular basis is unknown. By whole-exome sequencing we identify EMP3, encoding epithelial membrane protein 3 (EMP3), as a candidate gene, then demonstrate inactivating mutations in ten known MAM-negative individuals. We show that EMP3, a purported tumour suppressor in various solid tumours, is expressed in erythroid cells. Disruption of EMP3 by CRISPR/Cas9 gene editing in an immortalised human erythroid cell line (BEL-A2) abolishes MAM expression. We find EMP3 to associate with, and stabilise, CD44 in the plasma membrane. Furthermore, cultured erythroid progenitor cells from MAM-negative individuals show markedly increased proliferation and higher reticulocyte yields, suggesting an important regulatory role for EMP3 in erythropoiesis and control of cell production. Our data establish MAM as a new blood group system and demonstrate an interaction of EMP3 with the cell surface signalling molecule CD44.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Proliferação de Células , Células Eritroides/citologia , Glicoproteínas de Membrana/genética , Antígenos de Grupos Sanguíneos/química , Antígenos de Grupos Sanguíneos/metabolismo , Plaquetas/metabolismo , Células Cultivadas , Membrana Eritrocítica/metabolismo , Células Eritroides/metabolismo , Humanos , Receptores de Hialuronatos/metabolismo , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Modelos Moleculares , Mutação , Fenótipo , Ligação Proteica , Sequenciamento Completo do Exoma
2.
Nat Commun ; 11(1): 2807, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32533074

RESUMO

The nuclear receptor binding SET domain protein 1 (NSD1) is recurrently mutated in human cancers including acute leukemia. We show that NSD1 knockdown alters erythroid clonogenic growth of human CD34+ hematopoietic cells. Ablation of Nsd1 in the hematopoietic system of mice induces a transplantable erythroleukemia. In vitro differentiation of Nsd1-/- erythroblasts is majorly impaired despite abundant expression of GATA1, the transcriptional master regulator of erythropoiesis, and associated with an impaired activation of GATA1-induced targets. Retroviral expression of wildtype NSD1, but not a catalytically-inactive NSD1N1918Q SET-domain mutant induces terminal maturation of Nsd1-/- erythroblasts. Despite similar GATA1 protein levels, exogenous NSD1 but not NSDN1918Q significantly increases the occupancy of GATA1 at target genes and their expression. Notably, exogenous NSD1 reduces the association of GATA1 with the co-repressor SKI, and knockdown of SKI induces differentiation of Nsd1-/- erythroblasts. Collectively, we identify the NSD1 methyltransferase as a regulator of GATA1-controlled erythroid differentiation and leukemogenesis.


Assuntos
Diferenciação Celular , Células Eritroides/metabolismo , Células Eritroides/patologia , Fator de Transcrição GATA1/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Leucemia Eritroblástica Aguda/metabolismo , Leucemia Eritroblástica Aguda/patologia , Adulto , Animais , Antígenos CD/metabolismo , Antígenos CD34/metabolismo , Linhagem Celular Tumoral , Linhagem da Célula , Cromatina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Eritroblastos/metabolismo , Fator de Transcrição GATA1/genética , Regulação Leucêmica da Expressão Gênica , Técnicas de Silenciamento de Genes , Hematopoese , Histona-Lisina N-Metiltransferase/genética , Humanos , Estimativa de Kaplan-Meier , Leucemia Eritroblástica Aguda/genética , Masculino , Camundongos , Ligação Proteica , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores da Transferrina/metabolismo
3.
DNA Cell Biol ; 39(5): 756-765, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32282232

RESUMO

Iron-sulfur (Fe-S) clusters are required for mitochondrial function. Fe-S cluster synthesis occurs in the mitochondria and iron uptake is required for mitochondrial biogenesis. However, Fe-S clusters inhibit the expression of the iron importer transferrin receptor 1 (TfR1), whereas lack of the Fe-S cluster stimulates TfR1 expression. Yet, it is unclear whether Fe-S cluster synthesis increases with mitochondria biogenesis and, in turn, whether this negatively modulates TfR1 expression. We manipulated peroxisome proliferator-activated receptor-gamma coactivator-1α expression to control mitochondrial biogenesis in a variety of cell types, including erythroid cells. We demonstrated that Fe-S cluster synthesis increases with mitochondria biogenesis but does not interfere with increasing TfR1 expression. In fact, TfR1 expression is stimulated through alternative means to meet iron requirement for mitochondria biogenesis. Furthermore, under enhanced mitochondria biogenesis, increased Fe-S cluster synthesis inhibits the function of iron-regulating protein (IRP)1 and hence stimulates the expression of 5'-aminolevulinate synthase 2 (ALAS2), a target of IRP1 and rate-limiting enzyme in erythroid heme biogenesis. Increased ALAS2 expression leads to enhanced heme production, hemoglobinization, and erythropoiesis. Therefore, our study also provides a mechanism to link mitochondrial biogenesis with erythropoiesis and has a potential therapeutic value in the treatment of blood disorders.


Assuntos
Ferro/metabolismo , Biogênese de Organelas , Enxofre/metabolismo , Células 3T3-L1 , 5-Aminolevulinato Sintetase/genética , Animais , Transporte Biológico/efeitos dos fármacos , Células Eritroides/citologia , Células Eritroides/metabolismo , Eritropoese/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Heme/biossíntese , Hemoglobinas/metabolismo , Humanos , Camundongos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/farmacologia
4.
Exp Hematol ; 82: 43-52.e4, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32014431

RESUMO

Aged hematopoietic stem cells (HSCs) undergo biased lineage priming and differentiation toward production of myeloid cells. A comprehensive understanding of gene regulatory mechanisms causing HSC aging is needed to devise new strategies to sustainably improve immune function in aged individuals. Here, a focused short hairpin RNA screen of epigenetic factors reveals that the histone acetyltransferase Kat6b regulates myeloid cell production from hematopoietic progenitor cells. Within the stem and progenitor cell compartment, Kat6b is highly expressed in long-term (LT)-HSCs and is significantly decreased with aging at the transcript and protein levels. Knockdown of Kat6b in young LT-HSCs causes skewed production of myeloid cells at the expense of erythroid cells both in vitro and in vivo. Transcriptome analysis identifies enrichment of aging and macrophage-associated gene signatures alongside reduced expression of self-renewal and multilineage priming signatures. Together, our work identifies KAT6B as a novel epigenetic regulator of hematopoietic differentiation and a target to improve aged immune function.


Assuntos
Envelhecimento/metabolismo , Diferenciação Celular , Células Eritroides/enzimologia , Regulação Enzimológica da Expressão Gênica , Histona Acetiltransferases/biossíntese , Células Progenitoras Mieloides/enzimologia , Envelhecimento/genética , Envelhecimento/patologia , Animais , Epigênese Genética , Células Eritroides/patologia , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Histona Acetiltransferases/genética , Masculino , Camundongos , Camundongos Transgênicos , Células Progenitoras Mieloides/patologia , Transcriptoma
5.
Nat Genet ; 52(2): 138-145, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31959994

RESUMO

Increased production of fetal hemoglobin (HbF) can ameliorate the severity of sickle cell disease and ß-thalassemia1. BCL11A represses the genes encoding HbF and regulates human hemoglobin switching through variation in its expression during development2-7. However, the mechanisms underlying the developmental expression of BCL11A remain mysterious. Here we show that BCL11A is regulated at the level of messenger RNA (mRNA) translation during human hematopoietic development. Despite decreased BCL11A protein synthesis earlier in development, BCL11A mRNA continues to be associated with ribosomes. Through unbiased genomic and proteomic analyses, we demonstrate that the RNA-binding protein LIN28B, which is developmentally expressed in a pattern reciprocal to that of BCL11A, directly interacts with ribosomes and BCL11A mRNA. Furthermore, we show that BCL11A mRNA translation is suppressed by LIN28B through direct interactions, independently of its role in regulating let-7 microRNAs, and that BCL11A is the major target of LIN28B-mediated HbF induction. Our results reveal a previously unappreciated mechanism underlying human hemoglobin switching that illuminates new therapeutic opportunities.


Assuntos
Hemoglobinas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras/genética , Adulto , Animais , Sítios de Ligação , Células Cultivadas , Células Eritroides/metabolismo , Eritropoese/genética , Regulação da Expressão Gênica , Hemoglobinas/genética , Humanos , Recém-Nascido , MicroRNAs/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , RNA Ribossômico 18S/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas Repressoras/metabolismo , Ribossomos/genética , Ribossomos/metabolismo
6.
Einstein (Sao Paulo) ; 18: eAO4966, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31994605

RESUMO

OBJECTIVE: To validate multilineage score system correlating results of flow cytometry, cytogenetics, cytomorphology and histology from samples of patients with suspected myelodysplastic syndrome or cytopenia of unknown origin. METHODS: A retrospective study analyzing laboratory data of 49 patients with suspected myelodysplastic syndrome or cytopenia of unknown origin, carried out between May and September 2017. The inclusion criteria were availability of flow cytometry results, and at least one more method, such as morphology, histology or cytogenetics. Thirty-eight patients were classified as diagnosis of myelodysplastic syndromes, whereas 11 were classified as normal. Patients were evaluated based on score systems, Ogata score and flow cytometry multilineage score. RESULTS: Comparing the scores obtained in the Ogata score and the multilineage score, it was observed that in four cases the Ogata score was zero or 1 point, while the multilineage score was higher than 3 points. In addition, in 12 cases with Ogata score of 2, the multilineage score was greater than 3. CONCLUSION: The flow cytometry multilineage score system demonstrated to be more effective in dysplasia analysis, by assessing the erythroid, monocytic, granulocytic and precursor cell lineages, apart from the parameters evaluated by the Ogata score.


Assuntos
Citometria de Fluxo/normas , Síndromes Mielodisplásicas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Células da Medula Óssea/patologia , Criança , Pré-Escolar , Análise Citogenética/métodos , Análise Citogenética/normas , Células Eritroides/patologia , Feminino , Citometria de Fluxo/métodos , Granulócitos/patologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Monócitos/patologia , Padrões de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto Jovem
7.
Nucleic Acids Res ; 48(2): 770-787, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31799629

RESUMO

Variants in ribosomal protein (RP) genes drive Diamond-Blackfan anemia (DBA), a bone marrow failure syndrome that can also predispose individuals to cancer. Inherited and sporadic RP gene variants are also linked to a variety of phenotypes, including malignancy, in individuals with no anemia. Here we report an individual diagnosed with DBA carrying a variant in the 5'UTR of RPL9 (uL6). Additionally, we report two individuals from a family with multiple cancer incidences carrying a RPL9 missense variant. Analysis of cells from these individuals reveals that despite the variants both driving pre-rRNA processing defects and 80S monosome reduction, the downstream effects are remarkably different. Cells carrying the 5'UTR variant stabilize TP53 and impair the growth and differentiation of erythroid cells. In contrast, ribosomes incorporating the missense variant erroneously read through UAG and UGA stop codons of mRNAs. Metabolic profiles of cells carrying the 5'UTR variant reveal an increased metabolism of amino acids and a switch from glycolysis to gluconeogenesis while those of cells carrying the missense variant reveal a depletion of nucleotide pools. These findings indicate that variants in the same RP gene can drive similar ribosome biogenesis defects yet still have markedly different downstream consequences and clinical impacts.


Assuntos
Anemia de Diamond-Blackfan/genética , Processamento Pós-Transcricional do RNA/genética , Proteínas Ribossômicas/genética , Ribossomos/genética , Regiões 5' não Traduzidas/genética , Adolescente , Adulto , Anemia de Diamond-Blackfan/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Criança , Células Eritroides , Feminino , Humanos , Masculino , Mutação/genética , Precursores de RNA/genética , RNA Mensageiro/genética , Sequenciamento Completo do Exoma
8.
Exp Hematol ; 81: 16-31.e4, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31887343

RESUMO

We previously studied the role of ß1 integrin and some of its different α partners relevant to erythropoiesis. Although clear and consistent answers regarding the role of α4ß1 (VLA-4) were evident, the role of its companion integrin α5ß1 (VLA-5) was clouded by inconsistent outcomes in all prior publications. Furthermore, the functional consequences of integrin deficiencies only in microenvironmental (ME) cells supporting erythroid cell expansion and maturation post stress have never been explored. In the study described here, we created several additional mouse models in the aim of addressing unanswered questions regarding functional consequences of single or combined integrin deficiencies in erythroid cells or only in ME supporting cells. Our novel and expansive data solidified the intrinsic requirement of both α4 and α5 integrins in erythroid cells for their proliferative expansion and maturation in response to stress; α5 integrin alone, deleted either early in all hematopoietic cells or only in erythroid cell, has only a redundant role in proliferative expansion and is dispensable for erythroid maturation. By contrast, α4 integrin, on its own, exerts a dominant effect on timely and optimal erythroid maturation. Deficiency of both α4 and α5 integrins in ME cells, including macrophages, does not negatively influence stress response by normal erythroid cells, in great contrast to the effect of ME cells deficient in all ß1 integrins. Collectively the present data offer deeper insight into the coordination of different ß1 integrin functional activities in erythroid cells or in ME cells for optimal erythroid stress response.


Assuntos
Células Eritroides/metabolismo , Eritropoese , Integrina alfa5/metabolismo , Nicho de Células-Tronco , Estresse Fisiológico , Animais , Células Eritroides/citologia , Integrina alfa4beta1/genética , Integrina alfa4beta1/metabolismo , Integrina alfa5/genética , Integrina alfa5beta1/genética , Integrina alfa5beta1/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout
9.
Hum Genomics ; 13(1): 66, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823818

RESUMO

Transcription factors (TFs) consisting of zinc fingers combined with BTB (for broad-complex, tram-track, and bric-a-brac) domain (ZBTB) are a highly conserved protein family that comprises a multifunctional and heterogeneous group of TFs, mainly modulating cell developmental events and cell fate. LRF/ZBTB7A, in particular, is reported to be implicated in a wide variety of physiological and cancer-related cell events. These physiological processes include regulation of erythrocyte maturation, B/T cell differentiation, adipogenesis, and thymic insulin expression affecting consequently insulin self-tolerance. In cancer, LRF/ZBTB7A has been reported to act either as oncogenic or as oncosuppressive factor by affecting specific cell processes (proliferation, apoptosis, invasion, migration, metastasis, etc) in opposed ways, depending on cancer type and molecular interactions. The molecular mechanisms via which LRF/ZBTB7A is known to exert either physiological or cancer-related cellular effects include chromatin organization and remodeling, regulation of the Notch signaling axis, cellular response to DNA damage stimulus, epigenetic-dependent regulation of transcription, regulation of the expression and activity of NF-κB and p53, and regulation of aerobic glycolysis and oxidative phosphorylation (Warburg effect). It is a pleiotropic TF, and thus, alterations to its expression status become detrimental for cell survival. This review summarizes its implication in different cellular activities and the commonly invoked molecular mechanisms triggered by LRF/ZBTB7A's orchestrated action.


Assuntos
Fatores de Transcrição/metabolismo , Adipogenia/genética , Animais , Células Eritroides/metabolismo , Humanos , Neoplasias/metabolismo , Oncogenes , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/metabolismo
10.
mBio ; 10(6)2019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31772057

RESUMO

CD71+ erythroid cells (CECs) have a wide range of immunomodulatory properties. Here, we show that CECs are expanded in the peripheral blood of HIV patients, with a positive correlation between their frequency and the plasma viral load. CECs from HIV patients and human cord blood/placenta exacerbate HIV-1 infection/replication when cocultured with CD4+ T cells, and that preexposure of CD4+ T cells to CECs enhances their permissibility to HIV infection. However, mature red blood cells (RBCs) do not enhance HIV replication when cocultured with CD4+ T cells. We also found CECs express substantial levels of the NOX2 gene and via a mitochondrial reactive oxygen species (ROS)-dependent mechanism possibly upregulate NF-κB in CD4+ T cells once cocultured, which affects the cell cycle machinery to facilitate HIV-1 replication. The complement receptor-1 (CD35) and the Duffy antigen receptor for chemokines (DARC) as potential HIV target molecules are expressed significantly higher on CECs compared to mature red blood cells. Blocking CD35 or DARC substantially abolishes HIV-1 transmission by RBCs to uninfected CD4+ T cells but not by CECs. In contrast, we observed CECs bind to HIV-1 via CD235a and subsequently transfer the virus to uninfected CD4+ T cells, which can be partially blocked by the anti-CD235a antibody. More importantly, we found that CECs from HIV-infected individuals in the presence of antiretroviral therapy harbor infective viral particles, which mediate HIV-1 trans-infection of CD4+ T cells. Therefore, our findings provide a novel insight into the role of CECs in HIV pathogenesis as potential contributing cells in viral persistence and transmission.IMPORTANCE Immature red blood cells (erythroid precursors or CD71+ erythroid cells) have a wide range of immunomodulatory properties. In this study, we found that these erythroid precursors are abundant in the human cord blood/placental tissues, in the blood of HIV-infected and anemic individuals. We observed that these cells exacerbate HIV-1 replication/infection in target cells and even make HIV target cells more permissible to HIV infection. In addition, we found that HIV gets a free ride by binding on the surface of these cells and thus can travel to different parts of the body. In agreement, we noticed a positive correlation between the plasma viral load and the frequency of these cells in HIV patients. More importantly, we observed that infective HIV particles reside inside these erythroid precursors but not mature red blood cells. Therefore, these cells by harboring HIV can play an important role in HIV pathogenesis.


Assuntos
Células Eritroides/virologia , Infecções por HIV/virologia , HIV-1/fisiologia , Antígenos CD/genética , Antígenos CD/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Células Cultivadas , Células Eritroides/imunologia , Feminino , Sangue Fetal/imunologia , Sangue Fetal/virologia , Infecções por HIV/genética , Infecções por HIV/imunologia , HIV-1/genética , Humanos , Gravidez , Receptores da Transferrina/genética , Receptores da Transferrina/imunologia , Replicação Viral
11.
G3 (Bethesda) ; 9(12): 4149-4157, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31619461

RESUMO

Ribosome is a vital molecular machine for protein translation in the cell. Defects in several ribosomal proteins including RPS19, RPL11 and RPS14 have been observed in two types of anemia: Diamond Blackfan Anemia and 5q- syndrome. In zebrafish, deficiency of these ribosomal proteins shows similar anemic phenotype. It remains to be determined if any other ribosome proteins are similarly involved in regulating erythropoiesis. Here we generated mutations in zebrafish rps9, a rarely studied ribosomal protein gene, and investigated its function. Analysis of this mutant demonstrates that rps9 disruption leads to impairment of erythrocyte maturation, resulting in anemia. In addition, the overall phenotype including the anemic state is p53-dependent in rps9 mutants. Furthermore, this anemic state can be partially relieved by the treatment of L-leucine, and dexamethasone, which have been previously used in rescuing the phenotype of other ribosomal protein mutants. Finally, by comparing the phenotype, we show that there are considerable differences in morphology, cytomorphology, and hemoglobin levels for four ribosomal protein mutants in zebrafish. Based on the observed difference, we suggest that the level of anemic severity correlates with the delayed status of erythrocyte maturation in zebrafish models.


Assuntos
Anemia/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas de Peixe-Zebra/deficiência , Peixe-Zebra/metabolismo , Animais , Regulação para Baixo/genética , Embrião não Mamífero/anormalidades , Embrião não Mamífero/metabolismo , Células Eritroides/metabolismo , Células Eritroides/patologia , Regulação da Expressão Gênica no Desenvolvimento , Hemoglobinas/metabolismo , Mutação/genética , Fenótipo , Regulação para Cima/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
12.
Nat Cell Biol ; 21(11): 1449-1461, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31659274

RESUMO

Development and differentiation are associated with profound changes to histone modifications, yet their in vivo function remains incompletely understood. Here, we generated mouse models expressing inducible histone H3 lysine-to-methionine (K-to-M) mutants, which globally inhibit methylation at specific sites. Mice expressing H3K36M developed severe anaemia with arrested erythropoiesis, a marked haematopoietic stem cell defect, and rapid lethality. By contrast, mice expressing H3K9M survived up to a year and showed expansion of multipotent progenitors, aberrant lymphopoiesis and thrombocytosis. Additionally, some H3K9M mice succumbed to aggressive T cell leukaemia/lymphoma, while H3K36M mice exhibited differentiation defects in testis and intestine. Mechanistically, induction of either mutant reduced corresponding histone trimethylation patterns genome-wide and altered chromatin accessibility as well as gene expression landscapes. Strikingly, discontinuation of transgene expression largely restored differentiation programmes. Our work shows that individual chromatin modifications are required at several specific stages of differentiation and introduces powerful tools to interrogate their roles in vivo.


Assuntos
Epigênese Genética , Histonas/metabolismo , Leucemia de Células T/genética , Lisina/metabolismo , Metionina/metabolismo , Teratoma/genética , Animais , Transplante de Medula Óssea , Linhagem da Célula/genética , Modelos Animais de Doenças , Doxiciclina/farmacologia , Células Eritroides/metabolismo , Células Eritroides/patologia , Feminino , Granulócitos/metabolismo , Granulócitos/patologia , Histonas/genética , Leucemia de Células T/induzido quimicamente , Leucemia de Células T/metabolismo , Leucemia de Células T/patologia , Masculino , Metilação , Camundongos , Camundongos Transgênicos , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Embrionárias Murinas/patologia , Mutação , Transdução de Sinais , Análise de Sobrevida , Linfócitos T/metabolismo , Linfócitos T/patologia , Teratoma/induzido quimicamente , Teratoma/metabolismo , Teratoma/patologia
13.
PLoS One ; 14(9): e0221472, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31483850

RESUMO

Our previous single-cell based gene expression analysis pointed out significant variations of LDHA level during erythroid differentiation. Deeper investigations highlighted that a metabolic switch occurred along differentiation of erythroid cells. More precisely we showed that self-renewing progenitors relied mostly upon lactate-productive glycolysis, and required LDHA activity, whereas differentiating cells, mainly involved mitochondrial oxidative phosphorylation (OXPHOS). These metabolic rearrangements were coming along with a particular temporary event, occurring within the first 24h of erythroid differentiation. The activity of glycolytic metabolism and OXPHOS rose jointly with oxgene consumption dedicated to ATP production at 12-24h of the differentiation process before lactate-productive glycolysis sharply fall down and energy needs decline. Finally, we demonstrated that the metabolic switch mediated through LDHA drop and OXPHOS upkeep might be necessary for erythroid differentiation. We also discuss the possibility that metabolism, gene expression and epigenetics could act together in a circular manner as a driving force for differentiation.


Assuntos
Diferenciação Celular , Metabolismo Energético , Trifosfato de Adenosina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Galinhas , Metabolismo Energético/efeitos dos fármacos , Células Eritroides/citologia , Células Eritroides/metabolismo , Glicólise/efeitos dos fármacos , Isocumarinas/farmacologia , Lactato Desidrogenase 5/antagonistas & inibidores , Lactato Desidrogenase 5/genética , Lactato Desidrogenase 5/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos
14.
Exp Hematol ; 78: 21-34.e3, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31562902

RESUMO

Mouse models are widely used to study human erythropoiesis in vivo. One important caveat using mouse models is that mice often develop significant extramedullary erythropoiesis with anemia, which could mask important phenotypes. To overcome this drawback in mice, here we established in vitro and in vivo rat models for the studies of stress erythropoiesis. Using flow cytometry-based assays, we can monitor terminal erythropoiesis in rats during fetal and adult erythropoiesis under steady state and stress conditions. We used this system to test rat erythropoiesis under phenylhydrazine (PHZ)-induced hemolytic stress. In contrast to mice, rats did not have an increased proportion of early-stage erythroid precursors during terminal differentiation in the spleen or bone marrow. This could be explained by the abundant bone marrow spaces in rats that allow sufficient erythroid proliferation under stress. Consistently, the extent of splenomegaly in rats after PHZ treatment was significantly lower than that in mice. The level of BMP4, which was significantly increased in mouse spleen after PHZ treatment, remained unchanged in rat spleen. We further demonstrated that the bone marrow c-Kit positive progenitor population underwent a phenotype shift and became more CD71 positive and erythroid skewed with the expression of maturing erythroid markers under stress in rats and humans. In contrast, the phenotype shift to an erythroid-skewed progenitor population in mice occurred mainly in the spleen. Our study establishes rat in vitro and in vivo erythropoiesis models that are more appropriate and superior for the study of human stress erythropoiesis than mouse models.


Assuntos
Células Eritroides/metabolismo , Eritropoese/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Modelos Biológicos , Fenil-Hidrazinas/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Eritroides/patologia , Humanos , Camundongos , Ratos
15.
Int J Nanomedicine ; 14: 5581-5594, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413564

RESUMO

Background: Chronic myeloid leukemia (CML) is a myeloproliferative disorder due to the existence of BCR-ABL fusion protein that allows the cells to keep proliferating uncontrollably. Although tyrosine kinase inhibitors can inhibit the activity of BCR-ABL fusion protein to trigger the cells apoptosis, drug resistance or intolerance exists in part of CML patients. Arsenic sulfide in its raw form (r-As4S4) can be orally administrated and certain therapeutic effects have been found out in the treatment of hematologic malignancies through inducing cell apoptosis. Methods: In this work, a water-dissolvable arsenic sulfide nanoformualtion (ee-As4S4) composed of As4S4 particulates with 470 nm in diameter and encapsulated by a kind of hydrophilic polymer was fabricated and applied to the CML cell line K562, K562/AO2 and primary cells from the bone marrow of CML patients. Results: Results showed that instead of inhibiting the activity of BCR-ABL, ee-As4S4 induced direct degradation of BCR-ABL in K562 cells within 6 hr incubation, followed by the occurrence of erythroid differentiation in K562 after 72 hr incubation, evidenced by the significantly upregulated CD235a and benzidine staining, which was not detectable with r-As4S4. The ee-As4S4-induced erythroid differentiation was also observed in K562/AO2 cells and bone marrow mononuclear cells of CML patients. Mechanistic studies indicated that ee-As4S4 induced autophagy by downregulating the level of intracellular ROS and hypoxia-inducible factor-1α significantly, which led to the subsequent degradation of BCR-ABL. When the concentration was increased, ee-As4S4 induced much more significant apoptosis and cell cycle arrest than r-As4S4, and the cytotoxicity of the former was about 178 times of the latter. Conclusion: ee-As4S4 was capable of inducing significant erythroid differentiation of CML cells by inducing the direct degradation of BCR-ABL; the new effect could improve hematopoietic function of CML patients as well as inhibit the leukemic cell proliferation.


Assuntos
Arsenicais/farmacologia , Diferenciação Celular/efeitos dos fármacos , Composição de Medicamentos , Células Eritroides/citologia , Proteínas de Fusão bcr-abl/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Nanopartículas/química , Proteólise/efeitos dos fármacos , Sulfetos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Células Eritroides/efeitos dos fármacos , Células Eritroides/ultraestrutura , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Science ; 365(6455): 786-793, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31395745

RESUMO

How cellular and organismal complexity emerges from combinatorial expression of genes is a central question in biology. High-content phenotyping approaches such as Perturb-seq (single-cell RNA-sequencing pooled CRISPR screens) present an opportunity for exploring such genetic interactions (GIs) at scale. Here, we present an analytical framework for interpreting high-dimensional landscapes of cell states (manifolds) constructed from transcriptional phenotypes. We applied this approach to Perturb-seq profiling of strong GIs mined from a growth-based, gain-of-function GI map. Exploration of this manifold enabled ordering of regulatory pathways, principled classification of GIs (e.g., identifying suppressors), and mechanistic elucidation of synergistic interactions, including an unexpected synergy between CBL and CNN1 driving erythroid differentiation. Finally, we applied recommender system machine learning to predict interactions, facilitating exploration of vastly larger GI manifolds.


Assuntos
Epistasia Genética , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Apoptose/genética , Sistemas CRISPR-Cas , Proteínas de Ligação ao Cálcio/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Células Eritroides/citologia , Eritropoese/genética , Feminino , Perfilação da Expressão Gênica , Granulócitos/citologia , Humanos , Proteínas dos Microfilamentos/genética , Proteínas Proto-Oncogênicas c-cbl/genética
17.
PLoS One ; 14(8): e0217532, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31412036

RESUMO

Transcriptome analyses show a surprisingly large proportion of the mammalian genome is transcribed; much more than can be accounted for by genes and introns alone. Most of this transcription is non-coding in nature and arises from intergenic regions, often overlapping known protein-coding genes in sense or antisense orientation. The functional relevance of this widespread transcription is unknown. Here we characterize a promoter responsible for initiation of an intergenic transcript located approximately 3.3 kb and 10.7 kb upstream of the adult-specific human ß-globin genes. Mutational analyses in ß-YAC transgenic mice show that alteration of intergenic promoter activity results in ablation of H3K4 di- and tri-methylation and H3 hyperacetylation extending over a 30 kb region immediately downstream of the initiation site, containing the adult δ- and ß-globin genes. This results in dramatically decreased expression of the adult genes through position effect variegation in which the vast majority of definitive erythroid cells harbor inactive adult globin genes. In contrast, expression of the neighboring ε- and γ-globin genes is completely normal in embryonic erythroid cells, indicating a developmentally specific variegation of the adult domain. Our results demonstrate a role for intergenic non-coding RNA transcription in the propagation of histone modifications over chromatin domains and epigenetic control of ß-like globin gene transcription during development.


Assuntos
Cromatina/genética , DNA Intergênico/genética , Regulação da Expressão Gênica no Desenvolvimento , Histonas/química , Regiões Promotoras Genéticas , RNA não Traduzido/genética , Globinas beta/genética , Adulto , Animais , Cromossomos Artificiais de Levedura , Células Eritroides/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Transcrição Genética
18.
Anticancer Res ; 39(8): 4495-4502, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366551

RESUMO

BACKGROUND/AIM: In mice, fetal liver is the first tissue of definitive erythropoiesis for definitive erythroid expansion and maturation. ZFAT, originally identified as a candidate susceptibility gene for autoimmune thyroid disease, has been reported to be involved in primitive hematopoiesis and T cell development. The aim of this study was to examine whether or not Zfat is involved in definitive erythropoiesis in the fetal liver during mammalian development. MATERIALS AND METHODS: The role of Zfat during mouse fetal erythropoiesis in the fetal liver was examined using tamoxifen-inducible CreERT2 Zfat-deficient mice. RESULTS: Zfat-deficient mice exhibit moderate anemia with small and pale fetal liver through a decreased number of erythroblasts by E12.5. Apoptosis sensitivity in fetal liver erythroid progenitors was enhanced by Zfat-deficiency ex vivo. Moreover, Zfat knockdown partially inhibited CD71-/lowTer119- to CD71highTer119- transition of fetal liver erythroid progenitors with impairment in the elevation of CD71 expression. CONCLUSION: Zfat plays a critical role for erythropoiesis in the fetal liver.


Assuntos
Antígenos CD/genética , Eritropoese/genética , Fígado/crescimento & desenvolvimento , Receptores da Transferrina/genética , Fatores de Transcrição/genética , Animais , Apoptose/genética , Diferenciação Celular/genética , Células Eritroides/metabolismo , Células Eritroides/patologia , Desenvolvimento Fetal/genética , Feto , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Humanos , Fígado/metabolismo , Camundongos , Linfócitos T/citologia , Linfócitos T/metabolismo , Tireoidite Autoimune/genética , Tireoidite Autoimune/patologia
19.
Indian J Pathol Microbiol ; 62(3): 418-422, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31361230

RESUMO

Background: CD71 or Transferrin receptor is expressed on the surface of erythroid lineage cells. CD71 expression has been found to be significantly increased in rapidly proliferating cells. Methods: This cross-sectional study included 37 bone marrow samples of acute leukemia cases diagnosed between October 2016 to April 2018. The samples were analysed on BD FACS Canto II. We evaluated the expression of CD71 on leukemic blasts and compared median fluorescent intensities (MFI) of blasts in different types of acute leukemias. Results: The 37 cases comprised of 21 Acute Myeloid Leukemia (AML), 13 B-Acute Lymphoblastic Leukemia (B-ALL), 2 T- Acute Lymphoblastic Leukemia (T-ALL) and 1 mixed phenotypic acute leukemia (MPAL), T/Myeloid. CD 71 expression was noted in 70.3% (n= 26/37) of acute leukemia cases. CD71 expression was most commonly observed in AML (n= 15/21;71.4%), followed by B-ALL (n= 9/13;69.2%) and T-ALL (n= 1/2;50%). Single case of MPAL revealed blasts positive for CD71. MFI of leukemic blasts of single CD71 positive T-ALL was found to be highest, followed by AML, MPAL (T/Myeloid) and least in B ALL. Of the AML cases, the blasts of AML-M6, acute promyelocytic leukemia and AML-M1 showed higher CD71 expression in terms of MFI. Conclusions: Surface CD71 expression is not only found in erythroid lineage cells, but also in proliferating cells. CD71 MFI is highest in T lymphoblasts followed by leukemic erythroblasts, myeloblasts and least in B lymphoblasts.


Assuntos
Antígenos CD/genética , Antígenos CD/imunologia , Proliferação de Células , Células Eritroides/imunologia , Leucemia Linfoide/diagnóstico , Receptores da Transferrina/genética , Receptores da Transferrina/imunologia , Doença Aguda , Biomarcadores/análise , Células da Medula Óssea/imunologia , Linhagem da Célula , Estudos Transversais , Citometria de Fluxo , Humanos , Imunofenotipagem , Leucemia Linfoide/classificação , Estudos Retrospectivos
20.
Am J Clin Pathol ; 152(5): 675-685, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31305869

RESUMO

OBJECTIVES: Increasingly, acute promyelocytic leukemia (APL) is treated with a combination of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO). This study characterizes bone marrow findings after ATRA/ATO therapy. METHODS: Bone marrow biopsies from 16 patients treated with ATRA/ATO and seven patients treated with ATRA/chemotherapy (CTX) for APL were evaluated. RESULTS: In ATRA/ATO cases, the marrow was likely to be hypercellular (79%) with a decreased myeloid:erythroid (M:E) ratio (88%), megaloblastoid maturation of erythroid precursors (100%), erythroid atypia (75%), and increased (88%) and atypical (75%) megakaryocytes. Significant myeloid atypia was only seen in extensive residual disease. The ATRA/CTX cases were less likely to be hypercellular (38%), have a M:E ratio of 1:1 or less (0%), exhibit significant erythroid atypia (0%), or have increased (0%) or atypical (38%) megakaryocytes. CONCLUSIONS: Bone marrow biopsies from patients treated with ATO have unusual but characteristic features. Despite variability in marrow findings, clinical outcomes were uniformly favorable.


Assuntos
Trióxido de Arsênio/uso terapêutico , Células da Medula Óssea/patologia , Medula Óssea/patologia , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/patologia , Adolescente , Adulto , Idoso , Biópsia , Células Eritroides/patologia , Feminino , Humanos , Cariótipo , Masculino , Megacariócitos/patologia , Pessoa de Meia-Idade , Células Mieloides/patologia , Células Progenitoras Mieloides/patologia , Resultado do Tratamento , Tretinoína/uso terapêutico , Adulto Jovem
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