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1.
Nat Methods ; 15(10): 785-788, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30202058

RESUMO

The structural flexibility of RNA underlies fundamental biological processes, but there are no methods for exploring the multiple conformations adopted by RNAs in vivo. We developed cross-linking of matched RNAs and deep sequencing (COMRADES) for in-depth RNA conformation capture, and a pipeline for the retrieval of RNA structural ensembles. Using COMRADES, we determined the architecture of the Zika virus RNA genome inside cells, and identified multiple site-specific interactions with human noncoding RNAs.

2.
Science ; 357(6346): 83-88, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28572454

RESUMO

A recent outbreak of Zika virus in Brazil has led to a simultaneous increase in reports of neonatal microcephaly. Zika targets cerebral neural precursors, a cell population essential for cortical development, but the cause of this neurotropism remains obscure. Here we report that the neural RNA-binding protein Musashi-1 (MSI1) interacts with the Zika genome and enables viral replication. Zika infection disrupts the binding of MSI1 to its endogenous targets, thereby deregulating expression of factors implicated in neural stem cell function. We further show that MSI1 is highly expressed in neural progenitors of the human embryonic brain and is mutated in individuals with autosomal recessive primary microcephaly. Selective MSI1 expression in neural precursors could therefore explain the exceptional vulnerability of these cells to Zika infection.


Assuntos
Genoma Viral , Microcefalia/metabolismo , Microcefalia/virologia , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Ligação a RNA/metabolismo , Replicação Viral , Infecção por Zika virus/virologia , Zika virus/fisiologia , Animais , Encéfalo/anormalidades , Encéfalo/metabolismo , Encéfalo/virologia , Cercopithecus aethiops , Criança , Feminino , Células HEK293 , Humanos , Masculino , Microcefalia/genética , Mutação , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/fisiologia , Células-Tronco Neurais/virologia , Células Vero , Zika virus/genética
3.
Nature ; 544(7650): 309-315, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28405027

RESUMO

The 2013-2016 West African epidemic caused by the Ebola virus was of unprecedented magnitude, duration and impact. Here we reconstruct the dispersal, proliferation and decline of Ebola virus throughout the region by analysing 1,610 Ebola virus genomes, which represent over 5% of the known cases. We test the association of geography, climate and demography with viral movement among administrative regions, inferring a classic 'gravity' model, with intense dispersal between larger and closer populations. Despite attenuation of international dispersal after border closures, cross-border transmission had already sown the seeds for an international epidemic, rendering these measures ineffective at curbing the epidemic. We address why the epidemic did not spread into neighbouring countries, showing that these countries were susceptible to substantial outbreaks but at lower risk of introductions. Finally, we reveal that this large epidemic was a heterogeneous and spatially dissociated collection of transmission clusters of varying size, duration and connectivity. These insights will help to inform interventions in future epidemics.


Assuntos
Ebolavirus/genética , Ebolavirus/fisiologia , Genoma Viral/genética , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Clima , Surtos de Doenças/estatística & dados numéricos , Ebolavirus/isolamento & purificação , Geografia , Doença pelo Vírus Ebola/epidemiologia , Humanos , Internacionalidade , Modelos Lineares , Epidemiologia Molecular , Filogenia , Viagem/legislação & jurisprudência , Viagem/estatística & dados numéricos
4.
Clin Infect Dis ; 63(10): 1353-1356, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27585800

RESUMO

We report on an Ebola virus disease (EVD) survivor who showed Ebola virus in seminal fluid 531 days after onset of disease. The persisting virus was sexually transmitted in February 2016, about 470 days after onset of symptoms, and caused a new cluster of EVD in Guinea and Liberia.


Assuntos
Surtos de Doenças , Ebolavirus/genética , Doença pelo Vírus Ebola , Sêmen/virologia , Doenças Virais Sexualmente Transmissíveis , Ebolavirus/isolamento & purificação , Feminino , Guiné , Doença pelo Vírus Ebola/transmissão , Doença pelo Vírus Ebola/virologia , Humanos , Masculino , Reação em Cadeia da Polimerase , RNA Viral/análise , Doenças Virais Sexualmente Transmissíveis/transmissão , Doenças Virais Sexualmente Transmissíveis/virologia , Sobreviventes
5.
J Virol ; 89(15): 7758-75, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25995244

RESUMO

UNLABELLED: Recombinant hepatitis C virus (HCV) clones propagated in human hepatoma cell cultures yield relatively low infectivity titers. Here, we adapted the JFH1-based Core-NS2 recombinant SA13/JFH1C3405G,A3696G (termed SA13/JFH1orig), of the poorly characterized genotype 5a, to Huh7.5 cells, yielding a virus with greatly improved spread kinetics and an infectivity titer of 6.7 log10 focus-forming units (FFU)/ml. We identified several putative adaptive amino acid changes. In head-to-head infections at fixed multiplicities of infection, one SA13/JFH1orig mutant termed SA13/JFH1Core-NS5B, containing 13 amino acid changes (R114W and V187A [Core]; V235L [E1]; T385P [E2]; L782V [p7]; Y900C [NS2]; N2034D, E2238G, V2252A, L2266P, and I2340T [NS5A]; A2500S and V2841A [NS5B]), displayed fitness comparable to that of the polyclonal high-titer adapted virus. Single-cycle virus production assays in CD81-deficient Huh7-derived cells demonstrated that these changes did not affect replication but increased HCV assembly and specific infectivity as early as 24 h posttransfection. Infectious coculture assays in Huh7.5 cells showed a significant increase in cell-to-cell transmission for SA13/JFH1Core-NS5B viruses as well as viruses with only p7 and nonstructural protein mutations. Interestingly, the E2 hypervariable region 1 (HVR1) mutation T385P caused (i) increased sensitivity to neutralizing patient IgG and human monoclonal antibodies AR3A and AR4A and (ii) increased accessibility of the CD81 binding site without affecting the usage of CD81 and SR-BI. We finally demonstrated that SA13/JFH1orig and SA13/JFH1Core-NS5B, with and without the E2 mutation T385P, displayed similar biophysical properties following iodixanol gradient ultracentrifugation. This study has implications for investigations requiring high virus concentrations, such as studies of HCV particle composition and development of whole-virus vaccine antigens. IMPORTANCE: Hepatitis C virus (HCV) is a major global health care burden, affecting more than 150 million people worldwide. These individuals are at high risk of developing severe end-stage liver diseases. No vaccine exists. While it is possible to produce HCV particles resembling isolates of all HCV genotypes in human hepatoma cells (HCVcc), production efficacy varies. Thus, for several important studies, including vaccine development, in vitro systems enabling high-titer production of diverse HCV strains would be advantageous. Our study offers important functional data on how cell culture-adaptive mutations identified in genotype 5a JFH1-based HCVcc permit high-titer culture by affecting HCV genesis through increasing virus assembly and HCV fitness by enhancing the virus specific infectivity and cell-to-cell transmission ability, without influencing the biophysical particle properties. High-titer HCVcc like the one described in this study may be pivotal in future vaccine-related studies where large quantities of infectious HCV particles are necessary.


Assuntos
Hepacivirus/fisiologia , Hepatite C/virologia , Fragmentos de Peptídeos/genética , Recombinação Genética , Proteínas do Core Viral/genética , Proteínas não Estruturais Virais/genética , Montagem de Vírus , Linhagem Celular Tumoral , Genótipo , Hepacivirus/genética , Hepatite C/genética , Hepatite C/metabolismo , Humanos , Mutação , Fragmentos de Peptídeos/metabolismo , Inoculações Seriadas , Tetraspanina 28/genética , Tetraspanina 28/metabolismo , Proteínas do Core Viral/metabolismo , Proteínas não Estruturais Virais/metabolismo
6.
J Virol ; 89(4): 2170-81, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25473061

RESUMO

UNLABELLED: Neutralizing antibodies (NAbs) targeting glycoprotein E2 are important for the control of hepatitis C virus (HCV) infection. One conserved antigenic site (amino acids 412 to 423) is disordered in the reported E2 structure, but a synthetic peptide mimicking this site forms a ß-hairpin in complex with three independent NAbs. Our structure of the same peptide in complex with NAb 3/11 demonstrates a strikingly different extended conformation. We also show that residues 412 to 423 are essential for virus entry but not for E2 folding. Together with the neutralizing capacity of the 3/11 Fab fragment, this indicates an unexpected structural flexibility within this epitope. NAbs 3/11 and AP33 (recognizing the extended and ß-hairpin conformations, respectively) display similar neutralizing activities despite converse binding kinetics. Our results suggest that HCV utilizes conformational flexibility as an immune evasion strategy, contributing to the limited immunogenicity of this epitope in patients, similar to the conformational flexibility described for other enveloped and nonenveloped viruses. IMPORTANCE: Approximately 180 million people worldwide are infected with hepatitis C virus (HCV), and neutralizing antibodies play an important role in controlling the replication of this major human pathogen. We show here that one of the most conserved antigenic sites within the major glycoprotein E2 (amino acids 412 to 423), which is disordered in the recently reported crystal structure of an E2 core fragment, can adopt different conformations in the context of the infectious virus particle. Recombinant Fab fragments recognizing different conformations of this antigenic site have similar neutralization activities in spite of converse kinetic binding parameters. Of note, an antibody response targeting this antigenic region is less frequent than those targeting other more immunogenic regions in E2. Our results suggest that the observed conformational flexibility in this conserved antigenic region contributes to the evasion of the humoral host immune response, facilitating chronicity and the viral spread of HCV within an infected individual.


Assuntos
Anticorpos Neutralizantes/imunologia , Hepacivirus/química , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/imunologia , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia , Epitopos/química , Epitopos/imunologia , Humanos , Evasão da Resposta Imune , Modelos Moleculares , Ligação Proteica , Conformação Proteica
7.
Hepatology ; 60(6): 1891-901, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25066844

RESUMO

UNLABELLED: Interferon-alpha (IFNα) has been used to treat chronic hepatitis C virus (HCV) infection for over 20 years with varying efficacy, depending on the infecting viral genotype. The mechanism of action of IFNα is not fully understood, but is thought to target multiple stages of the HCV lifecycle, inhibiting viral transcription and translation leading to a degradation of viral RNA and protein expression in the infected cell. IFNα induces the expression of an array of interferon-stimulated genes within minutes of receptor engagement; however, the impact of these early responses on the viral lifecycle are unknown. We demonstrate that IFNα inhibits the genesis of infectious extracellular HCV particles within 2 hours of treating infected cells, with minimal effect on the intracellular viral burden. Importantly, this short duration of IFNα treatment of infected cells significantly reduced cell-free and cell-to-cell dissemination. The secreted viral particles showed no apparent change in protein content or density, demonstrating that IFNα inhibits particle infectivity but not secretion rates. To investigate whether particles released from IFNα-treated cells have a reduced capacity to establish infection we used HCV lentiviral pseudotypes (HCVpp) and demonstrated a defect in cell entry. Using a panel of monoclonal antibodies targeting the E2 glycoprotein, we demonstrate that IFNα alters glycoprotein conformation and receptor utilization. CONCLUSION: These observations show a previously unreported and rapid effect of IFNα on HCV particle infectivity that inhibits de novo infection events. Evasion of this response may be a contributing factor in whether a patient achieves early or rapid virological response, a key indicator of progression to sustained virological response or clearance of viral infection.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Interferon-alfa/farmacologia , Linhagem Celular , Humanos , Conformação Proteica/efeitos dos fármacos , Proteínas do Envelope Viral/efeitos dos fármacos
8.
Hepatology ; 59(4): 1320-30, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24259385

RESUMO

UNLABELLED: Macrophages are critical components of the innate immune response in the liver. Chronic hepatitis C is associated with immune infiltration and the infected liver shows a significant increase in total macrophage numbers; however, their role in the viral life cycle is poorly understood. Activation of blood-derived and intrahepatic macrophages with a panel of Toll-like receptor agonists induce soluble mediators that promote hepatitis C virus (HCV) entry into polarized hepatoma cells. We identified tumor necrosis factor α (TNF-α) as the major cytokine involved in this process. Importantly, this effect was not limited to HCV; TNF-α increased the permissivity of hepatoma cells to infection by Lassa, measles and vesicular stomatitis pseudoviruses. TNF-α induced a relocalization of tight junction protein occludin and increased the lateral diffusion speed of HCV receptor tetraspanin CD81 in polarized HepG2 cells, providing a mechanism for their increased permissivity to support HCV entry. High concentrations of HCV particles could stimulate macrophages to express TNF-α, providing a direct mechanism for the virus to promote infection. CONCLUSION: This study shows a new role for TNF-α to increase virus entry and highlights the potential for HCV to exploit existing innate immune responses in the liver to promote de novo infection events.


Assuntos
Carcinoma Hepatocelular/virologia , Hepacivirus/fisiologia , Neoplasias Hepáticas/virologia , Ativação de Macrófagos/fisiologia , Macrófagos/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Internalização do Vírus , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Polaridade Celular/fisiologia , Células Hep G2 , Hepatite C/metabolismo , Hepatite C/fisiopatologia , Humanos , Imunidade Inata/fisiologia , Interleucina-1beta/fisiologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Ocludina/metabolismo , Tetraspanina 28/metabolismo , Junções Íntimas/fisiologia
9.
J Hepatol ; 58(6): 1074-80, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23353869

RESUMO

BACKGROUND & AIMS: Hepatitis C virus (HCV) poses a global health problem, with over 170 million chronically infected individuals at risk of developing progressive liver disease. The ability of a virus to spread within a host is a key determinant of its persistence and virulence. HCV can transmit in vitro by cell-free particle diffusion or via contact(s) between infected and naïve hepatocytes. However, limited information is available on the relative efficiency of these routes, our aim is to develop physiologically relevant assays to quantify these processes. METHODS: We developed a single-cycle infection assay to measure HCV transmission rates. RESULTS: We compared HCV spread in proliferating and arrested cell systems and demonstrated a significant reduction in cell-to-cell infection of arrested target cells. Comparison of cell-free and cell-to-cell virus spread demonstrated relatively poor transmission rates, with 10-50 infected producer cells required to infect a single naïve target cell. We found HCV strain J6/JFH to be 10-fold more efficient at spreading via the cell-to-cell route than cell-free, whereas SA13/JFH and HK6/JFH strains showed comparable rates of infection via both routes. Importantly, the level of infectious virus released from cells did not predict the ability of a virus to spread in vitro, highlighting the importance of studying cell-associated viruses. CONCLUSIONS: These studies demonstrate the relatively poor infectivity of HCV and highlight differences between strains in their efficiency and preferred route of transmission that may inform future therapeutic strategies that target virus entry.


Assuntos
Hepacivirus/fisiologia , Hepatócitos/virologia , Adesão Celular , Comunicação Celular , Linhagem Celular , Humanos , Receptores Depuradores Classe B/fisiologia
10.
Rev Med Virol ; 22(3): 182-93, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22392805

RESUMO

HCV is a blood-borne pathogen that affects approximately 3% of the global population and leads to progressive liver disease. Recent advances have identified an essential role for host cell molecules: tetraspanin CD81, scavenger receptor B1 and the tight junction proteins claudin-1 and occludin in HCV entry, suggesting a complex multi-step process. The conserved nature of this receptor-dependent step in the viral life cycle offers an attractive target for therapeutic intervention. Evidence is emerging that additional factors other than classical receptors, such as inflammatory mediators regulate the ability of hepatocytes to support HCV entry, and as such may provide potential avenues for drug design and development. In this review, we summarise the recent literature on HCV entry mechanisms with a view to realising the future potential of therapeutically targeting this process.


Assuntos
Hepacivirus/fisiologia , Hepatite C/metabolismo , Hepatite C/virologia , Receptores Virais/metabolismo , Internalização do Vírus , Animais , Hepacivirus/genética , Hepatite C/genética , Humanos , Receptores Virais/genética
11.
Gastroenterology ; 142(3): 634-643.e6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22138189

RESUMO

BACKGROUND & AIMS: Hepatitis C virus (HCV) infection leads to progressive liver disease and is associated with a variety of extrahepatic syndromes, including central nervous system (CNS) abnormalities. However, it is unclear whether such cognitive abnormalities are a function of systemic disease, impaired hepatic function, or virus infection of the CNS. METHODS: We measured levels of HCV RNA and expression of the viral entry receptor in brain tissue samples from 10 infected individuals (and 3 uninfected individuals, as controls) and human brain microvascular endothelial cells by using quantitative polymerase chain reaction and immunochemical and confocal imaging analyses. HCV pseudoparticles and cell culture-derived HCV were used to study the ability of endothelial cells to support viral entry and replication. RESULTS: Using quantitative polymerase chain reaction, we detected HCV RNA in brain tissue of infected individuals at significantly lower levels than in liver samples. Brain microvascular endothelia and brain endothelial cells expressed all of the recognized HCV entry receptors. Two independently derived brain endothelial cell lines, hCMEC/D3 and HBMEC, supported HCV entry and replication. These processes were inhibited by antibodies against the entry factors CD81, scavenger receptor BI, and claudin-1; by interferon; and by reagents that inhibit NS3 protease and NS5B polymerase. HCV infection promotes endothelial permeability and cellular apoptosis. CONCLUSIONS: Human brain endothelial cells express functional receptors that support HCV entry and replication. Virus infection of the CNS might lead to HCV-associated neuropathologies.


Assuntos
Barreira Hematoencefálica/virologia , Células Endoteliais/virologia , Hepacivirus/patogenicidade , Hepatite C/virologia , Microvasos/virologia , Adulto , Antivirais/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Permeabilidade Capilar , Estudos de Casos e Controles , Linhagem Celular Tumoral , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Células HEK293 , Hepacivirus/genética , Hepatite C/complicações , Hepatite C/mortalidade , Humanos , Imuno-Histoquímica , Fígado/virologia , Masculino , Microscopia Confocal , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Microvasos/patologia , Pessoa de Meia-Idade , RNA Viral/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores Virais/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Vírion/metabolismo , Internalização do Vírus , Replicação Viral
12.
J Virol ; 85(1): 596-605, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20962076

RESUMO

Hepatitis C virus (HCV) can initiate infection by cell-free particle and cell-cell contact-dependent transmission. In this study we use a novel infectious coculture system to examine these alternative modes of infection. Cell-to-cell transmission is relatively resistant to anti-HCV glycoprotein monoclonal antibodies and polyclonal immunoglobulin isolated from infected individuals, providing an effective strategy for escaping host humoral immune responses. Chimeric viruses expressing the structural proteins representing the seven major HCV genotypes demonstrate neutralizing antibody-resistant cell-to-cell transmission. HCV entry is a multistep process involving numerous receptors. In this study we demonstrate that, in contrast to earlier reports, CD81 and the tight-junction components claudin-1 and occludin are all essential for both cell-free and cell-to-cell viral transmission. However, scavenger receptor BI (SR-BI) has a more prominent role in cell-to-cell transmission of the virus, with SR-BI-specific antibodies and small-molecule inhibitors showing preferential inhibition of this infection route. These observations highlight the importance of targeting host cell receptors, in particular SR-BI, to control viral infection and spread in the liver.


Assuntos
Anticorpos Neutralizantes/imunologia , Hepacivirus/fisiologia , Anticorpos Anti-Hepatite C/imunologia , Receptores Depuradores Classe B/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Linhagem Celular Tumoral , Claudina-1 , Técnicas de Cocultura , Hepacivirus/imunologia , Hepacivirus/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Ocludina , Receptores Virais/genética , Receptores Virais/metabolismo , Receptores Depuradores Classe B/genética , Tetraspanina 28 , Junções Íntimas/genética , Junções Íntimas/metabolismo
13.
PLoS One ; 4(11): e7769, 2009 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-19901984

RESUMO

Herein we describe a mutant of the two-exon HIV-1 Tat protein, termed Nullbasic, that potently inhibits multiple steps of the HIV-1 replication cycle. Nullbasic was created by replacing the entire arginine-rich basic domain of wild type Tat with glycine/alanine residues. Like similarly mutated one-exon Tat mutants, Nullbasic exhibited transdominant negative effects on Tat-dependent transactivation. However, unlike previously reported mutants, we discovered that Nullbasic also strongly suppressed the expression of unspliced and singly-spliced viral mRNA, an activity likely caused by redistribution and thus functional inhibition of HIV-1 Rev. Furthermore, HIV-1 virion particles produced by cells expressing Nullbasic had severely reduced infectivity, a defect attributable to a reduced ability of the virions to undergo reverse transcription. Combination of these inhibitory effects on transactivation, Rev-dependent mRNA transport and reverse transcription meant that permissive cells constitutively expressing Nullbasic were highly resistant to a spreading infection by HIV-1. Nullbasic and its activities thus provide potential insights into the development of potent antiviral therapeutics that target multiple stages of HIV-1 infection.


Assuntos
Produtos do Gene tat/genética , HIV-1/genética , Replicação Viral/genética , Éxons , Técnica Indireta de Fluorescência para Anticorpo , Genes Dominantes , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Mutação , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Transcrição Genética , Vírion
14.
Curr HIV Res ; 5(5): 473-83, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17896967

RESUMO

The role of Tat in HIV-1 reverse transcription has been controversial largely because different studies have observed disparate effects of the Tat protein on reverse transcription. Studies of HIV-1 lacking a functional tat gene demonstrated a decrease in reverse transcription efficiency following infection of T-cells however, in vitro recombinant Tat(1-86) has been shown to inhibit RT activity. Here we show that 20-200 nM of both N-terminally histidine-tagged recombinant Tat(1-72) and Tat(1-86) stimulated reverse transcription by HIV-1 reverse transcriptase (RT) in vitro by 2-3 fold. However, both Tat species were efficient inhibitors of RT activity at 400 nM. The lower concentrations of Tat increased reverse transcription efficiency by facilitating multiple rounds of DNA synthesis, and this increase was either not seen or reduced when Tat proteins with multiply-mutated cysteine or basic domains were used. Tat-enhanced reverse transcription occurred in a RNA-independent manner, and required formation of a Tat-RT complex. Pull-down and immunoprecipitation experiments confirmed that Tat could interact with the RT p51 subunit, and mammalian two-hybrid experiments showed interaction between Tat and both the p51 and p66 subunits. Together these results provide evidence that Tat can stimulate reverse transcription through an interaction with RT.


Assuntos
Ativação Enzimática , Produtos do Gene tat/metabolismo , Transcriptase Reversa do HIV/metabolismo , HIV-1/enzimologia , Substituição de Aminoácidos/genética , DNA Viral/biossíntese , Produtos do Gene tat/genética , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/metabolismo , Humanos , Imunoprecipitação , Mutação de Sentido Incorreto , Ligação Proteica , Mapeamento de Interação de Proteínas , Técnicas do Sistema de Duplo-Híbrido , Produtos do Gene tat do Vírus da Imunodeficiência Humana
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