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1.
Proc Natl Acad Sci U S A ; 121(5): e2308776121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38252831

RESUMO

We present a drug design strategy based on structural knowledge of protein-protein interfaces selected through virus-host coevolution and translated into highly potential small molecules. This approach is grounded on Vinland, the most comprehensive atlas of virus-human protein-protein interactions with annotation of interacting domains. From this inspiration, we identified small viral protein domains responsible for interaction with human proteins. These peptides form a library of new chemical entities used to screen for replication modulators of several pathogens. As a proof of concept, a peptide from a KSHV protein, identified as an inhibitor of influenza virus replication, was translated into a small molecule series with low nanomolar antiviral activity. By targeting the NEET proteins, these molecules turn out to be of therapeutic interest in a nonalcoholic steatohepatitis mouse model with kidney lesions. This study provides a biomimetic framework to design original chemistries targeting cellular proteins, with indications going far beyond infectious diseases.


Assuntos
Influenza Humana , Vírus , Animais , Camundongos , Humanos , Proteoma , Peptídeos/farmacologia , Descoberta de Drogas
2.
Mol Ther Nucleic Acids ; 33: 57-74, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37435135

RESUMO

Genome engineering has become more accessible thanks to the CRISPR-Cas9 gene-editing system. However, using this technology in synthetic organs called "organoids" is still very inefficient. This is due to the delivery methods for the CRISPR-Cas9 machinery, which include electroporation of CRISPR-Cas9 DNA, mRNA, or ribonucleoproteins containing the Cas9-gRNA complex. However, these procedures are quite toxic for the organoids. Here, we describe the use of the "nanoblade (NB)" technology, which outperformed by far gene-editing levels achieved to date for murine- and human tissue-derived organoids. We reached up to 75% of reporter gene knockout in organoids after treatment with NBs. Indeed, high-level NB-mediated knockout for the androgen receptor encoding gene and the cystic fibrosis transmembrane conductance regulator gene was achieved with single gRNA or dual gRNA containing NBs in murine prostate and colon organoids. Likewise, NBs achieved 20%-50% gene editing in human organoids. Most importantly, in contrast to other gene-editing methods, this was obtained without toxicity for the organoids. Only 4 weeks are required to obtain stable gene knockout in organoids and NBs simplify and allow rapid genome editing in organoids with little to no side effects including unwanted insertion/deletions in off-target sites thanks to transient Cas9/RNP expression.

3.
Nucleic Acids Res ; 51(14): 7580-7601, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37254812

RESUMO

The selenocysteine (Sec) tRNA (tRNA[Ser]Sec) governs Sec insertion into selenoproteins by the recoding of a UGA codon, typically used as a stop codon. A homozygous point mutation (C65G) in the human tRNA[Ser]Sec acceptor arm has been reported by two independent groups and was associated with symptoms such as thyroid dysfunction and low blood selenium levels; however, the extent of altered selenoprotein synthesis resulting from this mutation has yet to be comprehensively investigated. In this study, we used CRISPR/Cas9 technology to engineer homozygous and heterozygous mutant human cells, which we then compared with the parental cell lines. This C65G mutation affected many aspects of tRNA[Ser]Sec integrity and activity. Firstly, the expression level of tRNA[Ser]Sec was significantly reduced due to an altered recruitment of RNA polymerase III at the promoter. Secondly, selenoprotein expression was strongly altered, but, more surprisingly, it was no longer sensitive to selenium supplementation. Mass spectrometry analyses revealed a tRNA isoform with unmodified wobble nucleotide U34 in mutant cells that correlated with reduced UGA recoding activities. Overall, this study demonstrates the pleiotropic effect of a single C65G mutation on both tRNA phenotype and selenoproteome expression.


Assuntos
Selênio , Humanos , Códon de Terminação , Mutação , Selênio/farmacologia , Selênio/metabolismo , Selenocisteína/genética , Selenocisteína/metabolismo , Selenoproteínas/genética , Proteoma
4.
Front Genome Ed ; 3: 604371, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34713246

RESUMO

Programmable nucleases have enabled rapid and accessible genome engineering in eukaryotic cells and living organisms. However, their delivery into human blood cells can be challenging. Here, we have utilized "nanoblades," a new technology that delivers a genomic cleaving agent into cells. These are modified murine leukemia virus (MLV) or HIV-derived virus-like particle (VLP), in which the viral structural protein Gag has been fused to Cas9. These VLPs are thus loaded with Cas9 protein complexed with the guide RNAs. Highly efficient gene editing was obtained in cell lines, IPS and primary mouse and human cells. Here, we showed that nanoblades were remarkably efficient for entry into human T, B, and hematopoietic stem and progenitor cells (HSPCs) thanks to their surface co-pseudotyping with baboon retroviral and VSV-G envelope glycoproteins. A brief incubation of human T and B cells with nanoblades incorporating two gRNAs resulted in 40 and 15% edited deletion in the Wiskott-Aldrich syndrome (WAS) gene locus, respectively. CD34+ cells (HSPCs) treated with the same nanoblades allowed 30-40% exon 1 drop-out in the WAS gene locus. Importantly, no toxicity was detected upon nanoblade-mediated gene editing of these blood cells. Finally, we also treated HSPCs with nanoblades in combination with a donor-encoding rAAV6 vector resulting in up to 40% of stable expression cassette knock-in into the WAS gene locus. Summarizing, this new technology is simple to implement, shows high flexibility for different targets including primary immune cells of human and murine origin, is relatively inexpensive and therefore gives important prospects for basic and clinical translation in the area of gene therapy.

5.
J Vis Exp ; (169)2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-33871447

RESUMO

The clustered regularly interspaced short palindromic repeats (CRISPR)-Cas system has democratized genome-editing in eukaryotic cells and led to the development of numerous innovative applications. However, delivery of the Cas9 protein and single-guide RNA (sgRNA) into target cells can be technically challenge. Classical viral vectors, such as those derived from lentiviruses (LVs) or adeno-associated viruses (AAVs), allow for efficient delivery of transgenes coding for the Cas9 protein and its associated sgRNA in many primary cells and in vivo. Nevertheless, these vectors can suffer from drawbacks such as integration of the transgene in the target cell genome, a limited cargo capacity, and long-term expression of the Cas9 protein and guide RNA in target cells. To overcome some of these problems, a delivery vector based on the murine Leukemia virus (MLV) was developed to package the Cas9 protein and its associated guide RNA in the absence of any coding transgene. By fusing the Cas9 protein to the C-terminus of the structural protein Gag from MLV, virus-like particles (VLPs) loaded with the Cas9 protein and sgRNA (named "Nanoblades") were formed. Nanoblades can be collected from the culture medium of producer cells, purified, quantified, and used to transduce target cells and deliver the active Cas9/sgRNA complex. Nanoblades deliver their ribonucleoprotein (RNP) cargo transiently and rapidly in a wide range of primary and immortalized cells and can be programmed for other applications, such as transient transcriptional activation of targeted genes, using modified Cas9 proteins. Nanoblades are capable of in vivo genome-editing in the liver of injected adult mice and in oocytes to generate transgenic animals. Finally, they can be complexed with donor DNA for "transfection-free" homology-directed repair. Nanoblade preparation is simple, relatively low-cost, and can be easily carried out in any cell biology laboratory.


Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas/genética , Ribonucleoproteínas/genética , Humanos , Transfecção
6.
Nature ; 590(7847): 660-665, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33597753

RESUMO

The repair of DNA double-strand breaks (DSBs) is essential for safeguarding genome integrity. When a DSB forms, the PI3K-related ATM kinase rapidly triggers the establishment of megabase-sized, chromatin domains decorated with phosphorylated histone H2AX (γH2AX), which act as seeds for the formation of DNA-damage response foci1. It is unclear how these foci are rapidly assembled to establish a 'repair-prone' environment within the nucleus. Topologically associating domains are a key feature of 3D genome organization that compartmentalize transcription and replication, but little is known about their contribution to DNA repair processes2,3. Here we show that topologically associating domains are functional units of the DNA damage response, and are instrumental for the correct establishment of γH2AX-53BP1 chromatin domains in a manner that involves one-sided cohesin-mediated loop extrusion on both sides of the DSB. We propose a model in which H2AX-containing nucleosomes are rapidly phosphorylated as they actively pass by DSB-anchored cohesin. Our work highlights the importance of chromosome conformation in the maintenance of genome integrity and demonstrates the establishment of a chromatin modification by loop extrusion.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , DNA/química , DNA/metabolismo , Conformação de Ácido Nucleico , Saccharomyces cerevisiae , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Proteínas Cromossômicas não Histona/metabolismo , DNA/genética , Genoma/genética , Histonas/metabolismo , Humanos , Nucleossomos/química , Nucleossomos/genética , Nucleossomos/metabolismo , Fosforilação , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
7.
Genes Dev ; 33(17-18): 1175-1190, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31395742

RESUMO

The ribosomal DNA (rDNA) represents a particularly unstable locus undergoing frequent breakage. DNA double-strand breaks (DSBs) within rDNA induce both rDNA transcriptional repression and nucleolar segregation, but the link between the two events remains unclear. Here we found that DSBs induced on rDNA trigger transcriptional repression in a cohesin- and HUSH (human silencing hub) complex-dependent manner throughout the cell cycle. In S/G2 cells, transcriptional repression is further followed by extended resection within the interior of the nucleolus, DSB mobilization at the nucleolar periphery within nucleolar caps, and repair by homologous recombination. We showed that nuclear envelope invaginations frequently connect the nucleolus and that rDNA DSB mobilization, but not transcriptional repression, involves the nuclear envelope-associated LINC complex and the actin pathway. Altogether, our data indicate that rDNA break localization at the nucleolar periphery is not a direct consequence of transcriptional repression but rather is an active process that shares features with the mobilization of persistent DSB in active genes and heterochromatin.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , DNA Ribossômico/genética , Regulação da Expressão Gênica/genética , RNA Longo não Codificante/metabolismo , Nucléolo Celular/metabolismo , Histonas/metabolismo , Recombinação Homóloga/genética , Membrana Nuclear/metabolismo
8.
Cells ; 8(6)2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31212706

RESUMO

The translation of selenoprotein mRNAs involves a non-canonical ribosomal event in which an in-frame UGA is recoded as a selenocysteine (Sec) codon instead of being read as a stop codon. The recoding machinery is centered around two dedicated RNA components: The selenocysteine insertion sequence (SECIS) located in the 3' UTR of the mRNA and the selenocysteine-tRNA (Sec-tRNA[Ser]Sec). This translational UGA-selenocysteine recoding event by the ribosome is a limiting stage of selenoprotein expression. Its efficiency is controlled by the SECIS, the Sec-tRNA[Ser]Sec and their interacting protein partners. In the present work, we used a recently developed CRISPR strategy based on murine leukemia virus-like particles (VLPs) loaded with Cas9-sgRNA ribonucleoproteins to inactivate the Sec-tRNA[Ser]Sec gene in human cell lines. We showed that these CRISPR-Cas9-VLPs were able to induce efficient genome-editing in Hek293, HepG2, HaCaT, HAP1, HeLa, and LNCaP cell lines and this caused a robust reduction of selenoprotein expression. The alteration of selenoprotein expression was the direct consequence of lower levels of Sec-tRNA[Ser]Sec and thus a decrease in translational recoding efficiency of the ribosome. This novel strategy opens many possibilities to study the impact of selenoprotein deficiency in hard-to-transfect cells, since these CRISPR-Cas9-VLPs have a wide tropism.


Assuntos
Sistemas CRISPR-Cas/genética , Códon de Terminação/genética , RNA de Transferência Aminoácido-Específico/genética , Ribossomos/metabolismo , Selenocisteína/metabolismo , Vírion/metabolismo , Sequência de Bases , Edição de Genes , Células HEK293 , Células HeLa , Humanos , Mutação INDEL/genética , Conformação de Ácido Nucleico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Transferência Aminoácido-Específico/química , Selênio/metabolismo , Selenoproteínas/genética , Selenoproteínas/metabolismo
10.
Nat Commun ; 10(1): 45, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30604748

RESUMO

Programmable nucleases have enabled rapid and accessible genome engineering in eukaryotic cells and living organisms. However, their delivery into target cells can be technically challenging when working with primary cells or in vivo. Here, we use engineered murine leukemia virus-like particles loaded with Cas9-sgRNA ribonucleoproteins (Nanoblades) to induce efficient genome-editing in cell lines and primary cells including human induced pluripotent stem cells, human hematopoietic stem cells and mouse bone-marrow cells. Transgene-free Nanoblades are also capable of in vivo genome-editing in mouse embryos and in the liver of injected mice. Nanoblades can be complexed with donor DNA for "all-in-one" homology-directed repair or programmed with modified Cas9 variants to mediate transcriptional up-regulation of target genes. Nanoblades preparation process is simple, relatively inexpensive and can be easily implemented in any laboratory equipped for cellular biology.


Assuntos
Proteína 9 Associada à CRISPR/genética , Edição de Genes/métodos , Vetores Genéticos/genética , RNA Guia de Cinetoplastídeos/genética , Ribonucleoproteínas/genética , Animais , Linhagem Celular Tumoral , Reparo do DNA/genética , Embrião de Mamíferos , Fibroblastos , Edição de Genes/economia , Genoma/genética , Células HEK293 , Células-Tronco Hematopoéticas , Humanos , Células-Tronco Pluripotentes Induzidas , Vírus da Leucemia Murina/genética , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Ativação Transcricional/genética
11.
PLoS Pathog ; 7(12): e1002422, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22174682

RESUMO

Autophagy is a conserved degradative pathway used as a host defense mechanism against intracellular pathogens. However, several viruses can evade or subvert autophagy to insure their own replication. Nevertheless, the molecular details of viral interaction with autophagy remain largely unknown. We have determined the ability of 83 proteins of several families of RNA viruses (Paramyxoviridae, Flaviviridae, Orthomyxoviridae, Retroviridae and Togaviridae), to interact with 44 human autophagy-associated proteins using yeast two-hybrid and bioinformatic analysis. We found that the autophagy network is highly targeted by RNA viruses. Although central to autophagy, targeted proteins have also a high number of connections with proteins of other cellular functions. Interestingly, immunity-associated GTPase family M (IRGM), the most targeted protein, was found to interact with the autophagy-associated proteins ATG5, ATG10, MAP1CL3C and SH3GLB1. Strikingly, reduction of IRGM expression using small interfering RNA impairs both Measles virus (MeV), Hepatitis C virus (HCV) and human immunodeficiency virus-1 (HIV-1)-induced autophagy and viral particle production. Moreover we found that the expression of IRGM-interacting MeV-C, HCV-NS3 or HIV-NEF proteins per se is sufficient to induce autophagy, through an IRGM dependent pathway. Our work reveals an unexpected role of IRGM in virus-induced autophagy and suggests that several different families of RNA viruses may use common strategies to manipulate autophagy to improve viral infectivity.


Assuntos
Autofagia/fisiologia , Proteínas de Ligação ao GTP/metabolismo , Infecções por Vírus de RNA/metabolismo , Infecções por Vírus de RNA/transmissão , Vírus de RNA/metabolismo , Sequência de Bases , Western Blotting , Biologia Computacional , Proteínas de Ligação ao GTP/genética , Células HeLa , Humanos , Microscopia Confocal , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Infecções por Vírus de RNA/genética , Vírus de RNA/genética , RNA Interferente Pequeno , Transfecção , Técnicas do Sistema de Duplo-Híbrido , Proteínas Virais/metabolismo
12.
J Virol ; 85(24): 13010-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21994455

RESUMO

The influenza virus transcribes and replicates its genome inside the nucleus of infected cells. Both activities are performed by the viral RNA-dependent RNA polymerase that is composed of the three subunits PA, PB1, and PB2, and recent studies have shown that it requires host cell factors to transcribe and replicate the viral genome. To identify these cellular partners, we generated a comprehensive physical interaction map between each polymerase subunit and the host cellular proteome. A total of 109 human interactors were identified by yeast two-hybrid screens, whereas 90 were retrieved by literature mining. We built the FluPol interactome network composed of the influenza virus polymerase (PA, PB1, and PB2) and the nucleoprotein NP and 234 human proteins that are connected through 279 viral-cellular protein interactions. Analysis of this interactome map revealed enriched cellular functions associated with the influenza virus polymerase, including host factors involved in RNA polymerase II-dependent transcription and mRNA processing. We confirmed that eight influenza virus polymerase-interacting proteins are required for virus replication and transcriptional activity of the viral polymerase. These are involved in cellular transcription (C14orf166, COPS5, MNAT1, NMI, and POLR2A), translation (EIF3S6IP), nuclear transport (NUP54), and DNA repair (FANCG). Conversely, we identified PRKRA, which acts as an inhibitor of the viral polymerase transcriptional activity and thus is required for the cellular antiviral response.


Assuntos
Interações Hospedeiro-Patógeno , Vírus da Influenza A Subtipo H1N1/patogenicidade , Virus da Influenza A Subtipo H5N1/patogenicidade , Mapeamento de Interação de Proteínas , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Virais/metabolismo , Humanos , Ligação Proteica , Técnicas do Sistema de Duplo-Híbrido , Replicação Viral
13.
Sci Transl Med ; 3(94): 94ra71, 2011 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-21813755

RESUMO

Chronic hepatitis C virus (HCV) infection, with its cohort of life-threatening complications, affects more than 200 million persons worldwide and has a prevalence of more than 10% in certain countries. Preventive and therapeutic vaccines against HCV are thus much needed. Neutralizing antibodies (NAbs) are the foundation for successful disease prevention for most established vaccines. However, for viruses that cause chronic infection such as HIV or HCV, induction of broad NAbs from recombinant vaccines has remained elusive. We developed a vaccine platform specifically aimed at inducing NAbs based on pseudotyped virus-like particles (VLPs) made with retroviral Gag. We report that VLPs pseudotyped with E2 and/or E1 HCV envelope glycoproteins induced high-titer anti-E2 and/or anti-E1 antibodies, as well as NAbs, in both mouse and macaque. The NAbs, which were raised against HCV 1a, cross-neutralized the five other genotypes tested (1b, 2a, 2b, 4, and 5). Thus, the described VLP platform, which can be pseudotyped with a vast array of virus envelope glycoproteins, represents a new approach to viral vaccine development.


Assuntos
Anticorpos Neutralizantes/biossíntese , Hepacivirus/imunologia , Proteínas Virais/imunologia , Vírion/imunologia , Animais , Reações Cruzadas , Anticorpos Anti-Hepatite C/biossíntese , Macaca , Camundongos , Dados de Sequência Molecular
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