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1.
Stem Cell Res Ther ; 15(1): 104, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600587

RESUMO

BACKGROUND: Microglia, the brain's resident immune cells, play vital roles in brain development, and disorders like Alzheimer's disease (AD). Human iPSC-derived microglia (iMG) provide a promising model to study these processes. However, existing iMG generation protocols face challenges, such as prolonged differentiation time, lack of detailed characterization, and limited gene function investigation via CRISPR-Cas9. METHODS: Our integrated toolkit for in-vitro microglia functional genomics optimizes iPSC differentiation into iMG through a streamlined two-step, 20-day process, producing iMG with a normal karyotype. We confirmed the iMG's authenticity and quality through single-cell RNA sequencing, chromatin accessibility profiles (ATAC-Seq), proteomics and functional tests. The toolkit also incorporates a drug-dependent CRISPR-ON/OFF system for temporally controlled gene expression. Further, we facilitate the use of multi-omic data by providing online searchable platform that compares new iMG profiles to human primary microglia: https://sherlab.shinyapps.io/IPSC-derived-Microglia/ . RESULTS: Our method generates iMG that closely align with human primary microglia in terms of transcriptomic, proteomic, and chromatin accessibility profiles. Functionally, these iMG exhibit Ca2 + transients, cytokine driven migration, immune responses to inflammatory signals, and active phagocytosis of CNS related substrates including synaptosomes, amyloid beta and myelin. Significantly, the toolkit facilitates repeated iMG harvesting, essential for large-scale experiments like CRISPR-Cas9 screens. The standalone ATAC-Seq profiles of our iMG closely resemble primary microglia, positioning them as ideal tools to study AD-associated single nucleotide variants (SNV) especially in the genome regulatory regions. CONCLUSIONS: Our advanced two-step protocol rapidly and efficiently produces authentic iMG. With features like the CRISPR-ON/OFF system and a comprehensive multi-omic data platform, our toolkit equips researchers for robust microglial functional genomic studies. By facilitating detailed SNV investigation and offering a sustainable cell harvest mechanism, the toolkit heralds significant progress in neurodegenerative disease drug research and therapeutic advancement.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Humanos , Microglia/metabolismo , Proteômica , Peptídeos beta-Amiloides , Genômica , Doença de Alzheimer/genética , Cromatina/genética , Cromatina/metabolismo
2.
Environ Sci Pollut Res Int ; 31(12): 18435-18447, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38347353

RESUMO

Adopting renewable energy consumption is one of the most important aspects of international efforts to combat climate change, improve energy security, and encourage the shift to a more robust and sustainable energy system. Therefore, the empirics and policymakers worldwide are searching for factors that can promote renewable energy consumption. This analysis intends to investigate the role of financial globalization and tourism on renewable energy consumption in Asia and sub-regions such as Central Asia, East Asia, South Asia, Southeast Asia, and West Asia. The analysis utilized the linear and nonlinear CS-ARDL methods. Long-run outcomes of the linear and nonlinear models confirm that a rise in financial globalization and tourism promotes renewable energy consumption in Asia and all sub-regions. However, the nonlinear model highlights that a fall in financial globalization hurts renewable energy consumption in Central and South Asian regions, and tourism only hurts renewable energy consumption in Asia. In addition, ICT, GDP, and GHG emissions help promote renewable energy consumption. These results suggest that Asian policymakers must increase collaboration in the financial sectors and promote sustainable tourism in the regions to promote renewable energy consumption.


Assuntos
Desenvolvimento Econômico , Turismo , Estudos Transversais , Energia Renovável , Ásia , Internacionalidade , Dióxido de Carbono/análise
3.
J Relig Health ; 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37166691

RESUMO

Life-threatening events including terminal illness intensify the search for meaning and incite individuals to get closer to religion. Terminal patients can often find religious practices as helpful as medical therapy for bettering both physical and mental health. The present research aims to explain the interaction between religion, spirituality, and social support in coping with terminal illness among Muslim hepatitis C patients in Pakistan. A semi-structured open-ended interview guide was utilized to collect the data. Participants expressed that the deployment of religious and spiritual beliefs along with socio-emotional support during illness fostered medical therapy. Participants also revealed that belief in God provided them the strength to be steadfast during the terminal stage of the disease. Religious beliefs enabled terminal participants to accept death as an eventual reality and a normal part of their lives. Furthermore, participants put forward their longing for those kinds of religious practices that terminal diseases usually restrained them from receiving. The emotional support stemming from social relationships also improved resilience to cope with the terminal stage of illness. The study concludes that the interplay of religion, spirituality, and social support normalizes the fear of death, lessens pain, and improves resilience among Muslim hepatitis C patients in Pakistan.

4.
ACS Omega ; 7(8): 6579-6590, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35252654

RESUMO

Layered structured Ca3Co4O9 has displayed great potential for thermoelectric (TE) renewable energy applications, as it is nontoxic and contains abundantly available constituent elements. In this work, we study the crystal structure and high-temperature TE properties of Ca3-2y Na2y Co4-y Mo y O9 (0 ≤ y ≤ 0.10) polycrystalline materials. Powder X-ray diffraction (XRD) analysis shows that all samples are single-phase samples and without any noticeable amount of the secondary phase. X-ray photoelectron spectroscopic (XPS) measurements depict the presence of a mixture of Co3+ and Co4+ valence states in these materials. The Seebeck coefficient (S) of dual-doped materials is significantly enhanced, and electrical resistivities (ρ) and thermal conductivities (κ) are decreased compared to the pristine compound. The maximum thermoelectric power factor (PF = S 2/ρ) and dimensionless figure of merit (zT) obtained for the y = 0.025 sample at 1000 K temperature are ∼3.2 × 10-4 W m-1 K-2 and 0.27, respectively. The zT value for Ca2.95Na0.05Co3.975Mo0.025O9 is about 2.5 times higher than that of the parent Ca3Co4O9 compound. These results demonstrate that dual doping of Na and Mo cations is a promising strategy for improving the high-temperature thermoelectric properties of Ca3Co4O9.

5.
Inorg Chem ; 60(23): 17824-17836, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34743519

RESUMO

A new series of Ba2-xBixCoRuO6 (0.0 ≤ x ≤ 0.6) hexagonal double perovskite oxides have been synthesized by a solid-state reaction method by substituting Ba with Bi. The polycrystalline materials are structurally characterized by the laboratory X-ray diffraction, synchrotron X-ray, and neutron powder diffraction. The lattice parameters are found to increase with increasing Bi doping despite the smaller ionic radius of Bi3+ compared to Ba2+. The expansion is attributed to the reduction of Co/Ru-site cations. Scanning electron microscopy further shows that the grain size increases with the Bi content. All Ba2-xBixCoRuO6 (0.0 ≤ x ≤ 0.6) samples exhibit p-type behavior, and the electrical resistivity (ρ) is consistent with a small polaron hopping model. The Seebeck coefficient (S) and thermal conductivity (κ) are improved significantly with Bi doping. High values of the power factor (PF ∼ 6.64 × 10-4 W/m·K2) and figure of merit (zT ∼ 0.23) are obtained at 618 K for the x = 0.6 sample. These results show that Bi doping is an effective approach for enhancing the thermoelectric properties of hexagonal Ba2-xBixCoRuO6 perovskite oxides.

6.
Inorg Chem ; 60(17): 13550-13556, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34405996

RESUMO

The hexagonal perovskite derivatives Ba3NbMoO8.5, Ba3NbWO8.5, and Ba3VWO8.5 have recently been reported to exhibit significant oxide ion conductivity. Here, we report the synthesis and crystal structure of the hexagonal perovskite derivative Ba3-xVMoO8.5-x. Rietveld refinement from neutron and X-ray diffraction data show that the cation vacancies are ordered on the M2 site, leading to a structure consisting of palmierite-like layers of M1Ox polyhedra separated by vacant octahedral layers. In contrast to other members of the Ba3M'M″O8.5 family, Ba3-xVMoO8.5-x is not stoichiometric and both barium and oxygen vacancies are present. Although synthesized in air at elevated temperatures, Ba3-xVMoO8.5-x is unstable at lower temperatures, as illustrated by the formation of BaCO3 and BaMoO4 by heat treatment in air at 400 °C. This precludes measurement of the electrical properties. However, bond-valence site energy (BVSE) calculations strongly suggest that oxide ion conductivity is present in Ba3-xVMoO8.5-x.

7.
J Relig Health ; 59(6): 3126-3140, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31529272

RESUMO

Academics acknowledge religiosity, spirituality and social support as socio-behavioral factors that influence patients' ability to deal with chronic illness. This study has attempted to describe empirical reality of how these factors influence patients. The sample of this study was 500 chronically ill hepatitis patients and was selected through the multistage sampling techniques. Through structured interview schedule, data were collected during the period of September 2016 to March 2017 from five most populated cities of Punjab (Pakistan). Data were analyzed through descriptive (frequency and percentage) and inferential statistics (Cronbach's alpha, Pearson correlation, and structural equation modeling). The study suggests some recommendations and suggestions to policy makers regarding the significance of religiosity, spirituality and social support as coping strategies during chronic illness. The findings illustrate that social support has more association with coping than religiosity and spirituality of the patients.


Assuntos
Adaptação Psicológica , Hepatite Crônica/psicologia , Religião e Psicologia , Apoio Social , Espiritualidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hepatite Crônica/terapia , Humanos , Islamismo , Masculino , Pessoa de Meia-Idade , Paquistão , Adulto Jovem
8.
Nat Genet ; 51(7): 1149-1159, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31253978

RESUMO

Developmental silencing of fetal globins serves as both a paradigm of spatiotemporal gene regulation and an opportunity for therapeutic intervention of ß-hemoglobinopathy. The nucleosome remodeling and deacetylase (NuRD) chromatin complex participates in γ-globin repression. We used pooled CRISPR screening to disrupt NuRD protein coding sequences comprehensively in human adult erythroid precursors. Essential for fetal hemoglobin (HbF) control is a non-redundant subcomplex of NuRD protein family paralogs, whose composition we corroborated by affinity chromatography and proximity labeling mass spectrometry proteomics. Mapping top functional guide RNAs identified key protein interfaces where in-frame alleles resulted in loss-of-function due to destabilization or altered function of subunits. We ascertained mutations of CHD4 that dissociate its requirement for cell fitness from HbF repression in both primary human erythroid precursors and transgenic mice. Finally we demonstrated that sequestering CHD4 from NuRD phenocopied these mutations. These results indicate a generalizable approach to discover protein complex features amenable to rational biochemical targeting.


Assuntos
Cromatina/genética , Células Eritroides/metabolismo , Hemoglobina Fetal/metabolismo , Regulação da Expressão Gênica , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/metabolismo , Mutagênese , Animais , Cromatina/metabolismo , Células Eritroides/citologia , Hemoglobina Fetal/genética , Humanos , Complexo Mi-2 de Remodelação de Nucleossomo e Desacetilase/genética , Camundongos , Camundongos Transgênicos , Domínios e Motivos de Interação entre Proteínas
9.
RSC Adv ; 9(54): 31274-31283, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35527926

RESUMO

We report the electrical, magnetic and magnetotransport properties of Na and Mo dual doped Ca3-2x Na2x Co4-x Mo x O9 (0 ≤ x ≤ 0.15) polycrystalline samples. The results indicate that the strength of ferrimagnetic interaction decreases with increase in doping, as is evident from the observed decrease in Curie temperatures (T C). The substitution of non-magnetic Mo6+ ions (4d0) in CoO2 layers and the presence of oxygen vacancies are responsible for decrease in ligand field strength, which results in an enhanced magnetization in the low doped x = 0.025 sample due to a change from the low spin to partial high spin electron configuration. The electrical resistivity of samples exhibits a semiconducting-like behavior in the low temperature range, a strongly correlated Fermi liquid-like behavior in the intermediate temperature range, and an incoherent metal-like behavior in the temperature range 210-300 K. All the samples show a large negative magnetoresistance (MR) at low temperature with a maximum MR value of -59% for the x = 0.025 sample at 2 K and 16 T applied field. The MR values follow the observed trend in magnetization at 5 K and sharply increase below the Curie temperatures of the samples, suggesting that the ferrimagnetic interactions are mainly responsible for the decrease in electrical resistivity under an applied magnetic field.

11.
Genome Biol ; 19(1): 169, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30340514

RESUMO

CRISPR/Cas9 pooled screening permits parallel evaluation of comprehensive guide RNA libraries to systematically perturb protein coding sequences in situ and correlate with functional readouts. For the analysis and visualization of the resulting datasets, we develop CRISPRO, a computational pipeline that maps functional scores associated with guide RNAs to genomes, transcripts, and protein coordinates and structures. No currently available tool has similar functionality. The ensuing genotype-phenotype linear and three-dimensional maps raise hypotheses about structure-function relationships at discrete protein regions. Machine learning based on CRISPRO features improves prediction of guide RNA efficacy. The CRISPRO tool is freely available at gitlab.com/bauerlab/crispro .


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes , Genoma , Mutagênese/genética , Fases de Leitura Aberta/genética , Linhagem Celular , Humanos , Anotação de Sequência Molecular , Estrutura Secundária de Proteína , RNA Guia de Cinetoplastídeos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
Cell ; 173(2): 430-442.e17, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29606353

RESUMO

Fetal hemoglobin (HbF, α2γ2) level is genetically controlled and modifies severity of adult hemoglobin (HbA, α2ß2) disorders, sickle cell disease, and ß-thalassemia. Common genetic variation affects expression of BCL11A, a regulator of HbF silencing. To uncover how BCL11A supports the developmental switch from γ- to ß- globin, we use a functional assay and protein binding microarray to establish a requirement for a zinc-finger cluster in BCL11A in repression and identify a preferred DNA recognition sequence. This motif appears in embryonic and fetal-expressed globin promoters and is duplicated in γ-globin promoters. The more distal of the duplicated motifs is mutated in individuals with hereditary persistence of HbF. Using the CUT&RUN approach to map protein binding sites in erythroid cells, we demonstrate BCL11A occupancy preferentially at the distal motif, which can be disrupted by editing the promoter. Our findings reveal that direct γ-globin gene promoter repression by BCL11A underlies hemoglobin switching.


Assuntos
Proteínas de Transporte/metabolismo , Hemoglobina Fetal/genética , Proteínas Nucleares/metabolismo , Sequência de Bases , Sítios de Ligação , Proteínas de Transporte/genética , Linhagem Celular , Cromatina/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Células Eritroides/citologia , Células Eritroides/metabolismo , Edição de Genes , Humanos , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Repressoras , Dedos de Zinco/genética , Globinas beta/genética , Talassemia beta/genética , Talassemia beta/patologia , gama-Globinas/genética
13.
RSC Adv ; 8(22): 12211-12221, 2018 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35539404

RESUMO

The detailed crystal structures and high temperature thermoelectric properties of polycrystalline Ca3-2x Na2x Co4-x W x O9 (0 ≤ x ≤ 0.075) samples have been investigated. Powder X-ray diffraction data show that all samples are phase pure, with no detectable traces of impurity. The diffraction peaks shift to lower angle values with increase in doping (x), which is consistent with larger ionic radii of Na+ and W6+ ions. X-ray photoelectron spectroscopy data reveal that a mixture of Co2+, Co3+ and Co4+ valence states are present in all samples. It has been observed that electrical resistivity (ρ), Seebeck coefficient (S) and thermal conductivity (κ) are all improved with dual doping of Na and W in Ca3Co4O9 system. A maximum power factor (PF) of 2.71 × 10-4 W m-1 K-2 has been obtained for x = 0.025 sample at 1000 K. The corresponding thermoelectric figure of merit (zT) for x = 0.025 sample is calculated to be 0.21 at 1000 K, which is ∼2.3 times higher than zT value of the undoped sample. These results suggest that Na and W dual doping is a promising approach for improving thermoelectric properties of Ca3Co4O9 system.

14.
J Clin Invest ; 127(8): 3065-3074, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28714864

RESUMO

The lack of mechanistic explanations for many genotype-phenotype associations identified by GWAS precludes thorough assessment of their impact on human health. Here, we conducted an expression quantitative trait locus (eQTL) mapping analysis in erythroblasts and found erythroid-specific eQTLs for ATP2B4, the main calcium ATPase of red blood cells (rbc). The same SNPs were previously associated with mean corpuscular hemoglobin concentration (MCHC) and susceptibility to severe malaria infection. We showed that Atp2b4-/- mice demonstrate increased MCHC, confirming ATP2B4 as the causal gene at this GWAS locus. Using CRISPR-Cas9, we fine mapped the genetic signal to an erythroid-specific enhancer of ATP2B4. Erythroid cells with a deletion of the ATP2B4 enhancer had abnormally high intracellular calcium levels. These results illustrate the power of combined transcriptomic, epigenomic, and genome-editing approaches in characterizing noncoding regulatory elements in phenotype-relevant cells. Our study supports ATP2B4 as a potential target for modulating rbc hydration in erythroid disorders and malaria infection.


Assuntos
ATPases Transportadoras de Cálcio/genética , Eritrócitos/citologia , Predisposição Genética para Doença , Malária/genética , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Animais , Sistemas CRISPR-Cas , Cálcio/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Mapeamento Cromossômico , Elementos Facilitadores Genéticos , Epigenômica , Eritroblastos/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Células HEK293 , Humanos , Malária/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Fenótipo , ATPases Transportadoras de Cálcio da Membrana Plasmática/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
15.
Blood ; 128(19): 2338-2342, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27707736

RESUMO

BCL11A, a repressor of human fetal (γ-)globin expression, is required for immune and hematopoietic stem cell functions and brain development. Regulatory sequences within the gene, which are subject to genetic variation affecting fetal globin expression, display hallmarks of an erythroid enhancer in cell lines and transgenic mice. As such, this enhancer is a novel, attractive target for therapeutic gene editing. To explore the roles of such sequences in vivo, we generated mice in which the orthologous 10-kb intronic sequences were removed. Bcl11a enhancer-deleted mice, Bcl11a(Δenh), phenocopy the BCL11A-null state with respect to alterations of globin expression, yet are viable and exhibit no observable blood, brain, or other abnormalities. These preclinical findings provide strong in vivo support for genetic modification of the enhancer for therapy of hemoglobin disorders.


Assuntos
Proteínas de Transporte/metabolismo , Elementos Facilitadores Genéticos/genética , Células Eritroides/metabolismo , Proteínas Nucleares/metabolismo , Animais , Sequência de Bases , Compartimento Celular , Proteínas de Ligação a DNA , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Inativação Gênica , Humanos , Camundongos , Camundongos Transgênicos , Proteínas Repressoras
16.
J Coll Physicians Surg Pak ; 26(2): 100-2, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26876394

RESUMO

OBJECTIVE: To compare the frequency of surgical site infections in patients with type II diabetes undergoing laparoscopic cholecystectomy as compared with non-diabetic patients. STUDY DESIGN: Cohort study. PLACE AND DURATION OF STUDY: Surgical Unit 2, Services Hospital, Lahore, from May to October 2012. METHODOLOGY: Patients were divided into two groups of 60 each, undergoing laparoscopic cholecystectomy. Group A comprised non-diabetic patients and group B comprised type II diabetic patients. Patients were followed postoperatively upto one month for the development of SSIs. Proportion of patients with surgical site infections or otherwise was compared between the groups using chi-square test with significance of p < 0.05. RESULTS: In group A, 35 patients were above the age of 40 years. In group B, 38 patients were above the age of 40 years. Four patients in group Adeveloped a surgical site infection. Seven patients in group B developed SSIs (p = 0.07). CONCLUSION: Presence of diabetes mellitus did not significantly affect the onset of surgical site infection in patients undergoing laparoscopic cholecystectomy.


Assuntos
Colecistectomia Laparoscópica , Diabetes Mellitus Tipo 2/complicações , Infecção da Ferida Cirúrgica/epidemiologia , Adulto , Idoso , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Fatores de Risco , Infecção da Ferida Cirúrgica/etiologia
17.
Science ; 351(6270): 285-9, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26816381

RESUMO

Genes encoding human ß-type globin undergo a developmental switch from embryonic to fetal to adult-type expression. Mutations in the adult form cause inherited hemoglobinopathies or globin disorders, including sickle cell disease and thalassemia. Some experimental results have suggested that these diseases could be treated by induction of fetal-type hemoglobin (HbF). However, the mechanisms that repress HbF in adults remain unclear. We found that the LRF/ZBTB7A transcription factor occupies fetal γ-globin genes and maintains the nucleosome density necessary for γ-globin gene silencing in adults, and that LRF confers its repressive activity through a NuRD repressor complex independent of the fetal globin repressor BCL11A. Our study may provide additional opportunities for therapeutic targeting in the treatment of hemoglobinopathies.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Hemoglobina Fetal/genética , Inativação Gênica , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , gama-Globinas/genética , Anemia Falciforme/genética , Animais , Proteínas de Transporte/genética , Linhagem Celular , Cromatina/metabolismo , Proteínas de Ligação a DNA/genética , Eritroblastos/citologia , Eritropoese/genética , Humanos , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Deleção de Sequência , Talassemia/genética , Fatores de Transcrição/genética
18.
Nature ; 527(7577): 192-7, 2015 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-26375006

RESUMO

Enhancers, critical determinants of cellular identity, are commonly recognized by correlative chromatin marks and gain-of-function potential, although only loss-of-function studies can demonstrate their requirement in the native genomic context. Previously, we identified an erythroid enhancer of human BCL11A, subject to common genetic variation associated with the fetal haemoglobin level, the mouse orthologue of which is necessary for erythroid BCL11A expression. Here we develop pooled clustered regularly interspaced palindromic repeat (CRISPR)-Cas9 guide RNA libraries to perform in situ saturating mutagenesis of the human and mouse enhancers. This approach reveals critical minimal features and discrete vulnerabilities of these enhancers. Despite conserved function of the composite enhancers, their architecture diverges. The crucial human sequences appear to be primate-specific. Through editing of primary human progenitors and mouse transgenesis, we validate the BCL11A erythroid enhancer as a target for fetal haemoglobin reinduction. The detailed enhancer map will inform therapeutic genome editing, and the screening approach described here is generally applicable to functional interrogation of non-coding genomic elements.


Assuntos
Proteínas Associadas a CRISPR/metabolismo , Proteínas de Transporte/genética , Elementos Facilitadores Genéticos/genética , Engenharia Genética , Mutagênese/genética , Proteínas Nucleares/genética , Animais , Sequência de Bases , Sistemas CRISPR-Cas/genética , Células Cultivadas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Proteínas de Ligação a DNA , Eritroblastos/metabolismo , Hemoglobina Fetal/genética , Genoma/genética , Humanos , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , RNA Guia de Cinetoplastídeos/genética , Proteínas Repressoras , Reprodutibilidade dos Testes , Especificidade da Espécie
19.
Inorg Chem ; 54(6): 2536-42, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25713929

RESUMO

We have recently reported a new mechanism of colossal magnetoresistance (CMR) in electron doped manganese oxypnictides NdMnAsO1-xFx. Magnetoresistances of up to -95% at 3 K have been observed. Here we show that upon replacing Nd for Pr, the CMR is surprisingly no longer present. Instead a sizable negative magnetoresistance is observed for PrMnAsO0.95F0.05 below 35 K (MR7T (12 K) = -13.4% for PrMnAsO0.95F0.05). A detailed neutron and synchrotron X-ray diffraction study of PrMnAsO0.95F0.05 has been performed, which shows that a structural transition, Ts, occurs at 35 K from tetragonal P4/nmm to orthorhombic Pmmn symmetry. The structural transition is driven by the Pr 4f electrons degrees of freedom. The sizable -MR observed below the transition most likely arises due to a reduction in magnetic and/or multipolar scattering upon application of a magnetic field.

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