RESUMEN
Chronic social isolation causes severe psychological effects in humans, but their neural bases remain poorly understood. 2 weeks (but not 24 hr) of social isolation stress (SIS) caused multiple behavioral changes in mice and induced brain-wide upregulation of the neuropeptide tachykinin 2 (Tac2)/neurokinin B (NkB). Systemic administration of an Nk3R antagonist prevented virtually all of the behavioral effects of chronic SIS. Conversely, enhancing NkB expression and release phenocopied SIS in group-housed mice, promoting aggression and converting stimulus-locked defensive behaviors to persistent responses. Multiplexed analysis of Tac2/NkB function in multiple brain areas revealed dissociable, region-specific requirements for both the peptide and its receptor in different SIS-induced behavioral changes. Thus, Tac2 coordinates a pleiotropic brain state caused by SIS via a distributed mode of action. These data reveal the profound effects of prolonged social isolation on brain chemistry and function and suggest potential new therapeutic applications for Nk3R antagonists.
Asunto(s)
Encéfalo/metabolismo , Neuroquinina B/metabolismo , Precursores de Proteínas/metabolismo , Aislamiento Social , Estrés Psicológico , Taquicininas/metabolismo , Animales , Antipsicóticos/farmacología , Conducta Animal/efectos de los fármacos , Encéfalo/patología , Femenino , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Neuroquinina B/genética , Neuronas/citología , Neuronas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Precursores de Proteínas/antagonistas & inhibidores , Precursores de Proteínas/genética , Interferencia de ARN , ARN Interferente Pequeño/genética , Receptores de Taquicininas/antagonistas & inhibidores , Receptores de Taquicininas/metabolismo , Taquicininas/antagonistas & inhibidores , Taquicininas/genética , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Understanding the structure-function relationships at cellular, circuit, and organ-wide scale requires 3D anatomical and phenotypical maps, currently unavailable for many organs across species. At the root of this knowledge gap is the absence of a method that enables whole-organ imaging. Herein, we present techniques for tissue clearing in which whole organs and bodies are rendered macromolecule-permeable and optically transparent, thereby exposing their cellular structure with intact connectivity. We describe PACT (passive clarity technique), a protocol for passive tissue clearing and immunostaining of intact organs; RIMS (refractive index matching solution), a mounting media for imaging thick tissue; and PARS (perfusion-assisted agent release in situ), a method for whole-body clearing and immunolabeling. We show that in rodents PACT, RIMS, and PARS are compatible with endogenous-fluorescence, immunohistochemistry, RNA single-molecule FISH, long-term storage, and microscopy with cellular and subcellular resolution. These methods are applicable for high-resolution, high-content mapping and phenotyping of normal and pathological elements within intact organs and bodies.
Asunto(s)
Células/clasificación , Imagenología Tridimensional/métodos , Análisis de la Célula Individual , Imagen de Cuerpo Entero , Animales , Encéfalo/citología , Células/metabolismo , Fluorescencia , Ratones , Microscopía Confocal/métodos , Microscopía Electrónica de Rastreo , FenotipoRESUMEN
Spatially charting molecular cell types at single-cell resolution across the 3D volume is critical for illustrating the molecular basis of brain anatomy and functions. Single-cell RNA sequencing has profiled molecular cell types in the mouse brain1,2, but cannot capture their spatial organization. Here we used an in situ sequencing method, STARmap PLUS3,4, to profile 1,022 genes in 3D at a voxel size of 194 × 194 × 345 nm3, mapping 1.09 million high-quality cells across the adult mouse brain and spinal cord. We developed computational pipelines to segment, cluster and annotate 230 molecular cell types by single-cell gene expression and 106 molecular tissue regions by spatial niche gene expression. Joint analysis of molecular cell types and molecular tissue regions enabled a systematic molecular spatial cell-type nomenclature and identification of tissue architectures that were undefined in established brain anatomy. To create a transcriptome-wide spatial atlas, we integrated STARmap PLUS measurements with a published single-cell RNA-sequencing atlas1, imputing single-cell expression profiles of 11,844 genes. Finally, we delineated viral tropisms of a brain-wide transgene delivery tool, AAV-PHP.eB5,6. Together, this annotated dataset provides a single-cell resource that integrates the molecular spatial atlas, brain anatomy and the accessibility to genetic manipulation of the mammalian central nervous system.
Asunto(s)
Sistema Nervioso Central , Imagenología Tridimensional , Análisis de la Célula Individual , Transcriptoma , Animales , Ratones , Encéfalo/anatomía & histología , Encéfalo/citología , Encéfalo/metabolismo , Sistema Nervioso Central/anatomía & histología , Sistema Nervioso Central/citología , Sistema Nervioso Central/metabolismo , Análisis de la Célula Individual/métodos , Médula Espinal/anatomía & histología , Médula Espinal/citología , Médula Espinal/metabolismo , Transcriptoma/genética , Análisis de Expresión Génica de una Sola Célula , Tropismo Viral , Conjuntos de Datos como Asunto , Transgenes/genética , Imagenología Tridimensional/métodosRESUMEN
The move from reading to writing the human genome offers new opportunities to improve human health. The United States National Institutes of Health (NIH) Somatic Cell Genome Editing (SCGE) Consortium aims to accelerate the development of safer and more-effective methods to edit the genomes of disease-relevant somatic cells in patients, even in tissues that are difficult to reach. Here we discuss the consortium's plans to develop and benchmark approaches to induce and measure genome modifications, and to define downstream functional consequences of genome editing within human cells. Central to this effort is a rigorous and innovative approach that requires validation of the technology through third-party testing in small and large animals. New genome editors, delivery technologies and methods for tracking edited cells in vivo, as well as newly developed animal models and human biological systems, will be assembled-along with validated datasets-into an SCGE Toolkit, which will be disseminated widely to the biomedical research community. We visualize this toolkit-and the knowledge generated by its applications-as a means to accelerate the clinical development of new therapies for a wide range of conditions.
Asunto(s)
Células/metabolismo , Edición Génica/métodos , Genoma Humano/genética , National Institutes of Health (U.S.)/organización & administración , Animales , Terapia Genética , Objetivos , Humanos , Estados UnidosRESUMEN
Recombinant viruses allow for targeted transgene expression in specific cell populations throughout the nervous system. The adeno-associated virus (AAV) is among the most commonly used viruses for neuroscience research. Recombinant AAVs (rAAVs) are highly versatile and can package most cargo composed of desired genes within the capsid's â¼5-kb carrying capacity. Numerous regulatory elements and intersectional strategies have been validated in rAAVs to enable cell type-specific expression. rAAVs can be delivered to specific neuronal populations or globally throughout the animal. The AAV capsids have natural cell type or tissue tropism and trafficking that can be modified for increased specificity. Here, we describe recently engineered AAV capsids and associated cargo that have extended the utility of AAVs in targeting molecularly defined neurons throughout the nervous system, which will further facilitate neuronal circuit interrogation and discovery.
Asunto(s)
Sistema Nervioso Central/fisiología , Ingeniería Genética , Sistema Nervioso Periférico/fisiología , Animales , Dependovirus/genética , HumanosRESUMEN
Viruses have evolved the ability to bind and enter cells through interactions with a wide variety of cell macromolecules. We engineered peptide-modified adeno-associated virus (AAV) capsids that transduce the brain through the introduction of de novo interactions with 2 proteins expressed on the mouse blood-brain barrier (BBB), LY6A or LY6C1. The in vivo tropisms of these capsids are predictable as they are dependent on the cell- and strain-specific expression of their target protein. This approach generated hundreds of capsids with dramatically enhanced central nervous system (CNS) tropisms within a single round of screening in vitro and secondary validation in vivo thereby reducing the use of animals in comparison to conventional multi-round in vivo selections. The reproducible and quantitative data derived via this method enabled both saturation mutagenesis and machine learning (ML)-guided exploration of the capsid sequence space. Notably, during our validation process, we determined that nearly all published AAV capsids that were selected for their ability to cross the BBB in mice leverage either the LY6A or LY6C1 protein, which are not present in primates. This work demonstrates that AAV capsids can be directly targeted to specific proteins to generate potent gene delivery vectors with known mechanisms of action and predictable tropisms.
Asunto(s)
Barrera Hematoencefálica , Cápside , Ratones , Animales , Barrera Hematoencefálica/metabolismo , Cápside/metabolismo , Vectores Genéticos , Sistema Nervioso Central/metabolismo , Proteínas de la Cápside/genética , Proteínas de la Cápside/metabolismo , Dependovirus/genética , Dependovirus/metabolismoRESUMEN
BACKGROUND: Copy number variations, and particularly duplications of genomic regions, have been strongly associated with various neurodegenerative conditions including autism spectrum disorder (ASD). These genetic variations have been found to have a significant impact on brain development and function, which can lead to the emergence of neurological and behavioral symptoms. Developing strategies to target these genomic duplications has been challenging, as the presence of endogenous copies of the duplicate genes often complicates the editing strategies. RESULTS: Using the ASD and anxiety mouse model Flailer, which contains a partial genomic duplication working as a dominant negative for MyoVa, we demonstrate the use of DN-CRISPRs to remove a 700 bp genomic region in vitro and in vivo. Importantly, DN-CRISPRs have not been used to remove genomic regions using sgRNA with an offset greater than 300 bp. We found that editing the flailer gene in primary cortical neurons reverts synaptic transport and transmission defects. Moreover, long-term depression (LTD), disrupted in Flailer animals, is recovered after gene editing. Delivery of DN-CRISPRs in vivo shows that local delivery to the ventral hippocampus can rescue some of the mutant behaviors, while intracerebroventricular delivery, completely recovers the Flailer animal phenotype associated to anxiety and ASD. CONCLUSIONS: Our results demonstrate the potential of DN-CRISPR to efficiently remove larger genomic duplications, working as a new gene therapy approach for treating neurodegenerative diseases.
Asunto(s)
Trastorno del Espectro Autista , Ratones , Animales , Trastorno del Espectro Autista/genética , Variaciones en el Número de Copia de ADN , ARN Guía de Sistemas CRISPR-Cas , Transmisión Sináptica/genética , GenómicaRESUMEN
Recombinant adeno-associated viruses (rAAVs) are efficient gene delivery vectors via intravenous delivery; however, natural serotypes display a finite set of tropisms. To expand their utility, we evolved AAV capsids to efficiently transduce specific cell types in adult mouse brains. Building upon our Cre-recombination-based AAV targeted evolution (CREATE) platform, we developed Multiplexed-CREATE (M-CREATE) to identify variants of interest in a given selection landscape through multiple positive and negative selection criteria. M-CREATE incorporates next-generation sequencing, synthetic library generation and a dedicated analysis pipeline. We have identified capsid variants that can transduce the central nervous system broadly, exhibit bias toward vascular cells and astrocytes, target neurons with greater specificity or cross the blood-brain barrier across diverse murine strains. Collectively, the M-CREATE methodology accelerates the discovery of capsids for use in neuroscience and gene-therapy applications.
Asunto(s)
Encéfalo/virología , Proteínas de la Cápside/metabolismo , Dependovirus/genética , Técnicas de Transferencia de Gen , Ingeniería Genética/métodos , Vectores Genéticos/genética , Integrasas/metabolismo , Animales , Barrera Hematoencefálica/metabolismo , Proteínas de la Cápside/genética , Femenino , Terapia Genética , Masculino , Ratones , Ratones Endogámicos C57BL , Especificidad de Órganos , Tropismo ViralRESUMEN
In situ hybridization methods are used across the biological sciences to map mRNA expression within intact specimens. Multiplexed experiments, in which multiple target mRNAs are mapped in a single sample, are essential for studying regulatory interactions, but remain cumbersome in most model organisms. Programmable in situ amplifiers based on the mechanism of hybridization chain reaction (HCR) overcome this longstanding challenge by operating independently within a sample, enabling multiplexed experiments to be performed with an experimental timeline independent of the number of target mRNAs. To assist biologists working across a broad spectrum of organisms, we demonstrate multiplexed in situ HCR in diverse imaging settings: bacteria, whole-mount nematode larvae, whole-mount fruit fly embryos, whole-mount sea urchin embryos, whole-mount zebrafish larvae, whole-mount chicken embryos, whole-mount mouse embryos and formalin-fixed paraffin-embedded human tissue sections. In addition to straightforward multiplexing, in situ HCR enables deep sample penetration, high contrast and subcellular resolution, providing an incisive tool for the study of interlaced and overlapping expression patterns, with implications for research communities across the biological sciences.
Asunto(s)
Hibridación in Situ/métodos , ARN Mensajero/metabolismo , Animales , Drosophila , Embrión no Mamífero/metabolismo , Humanos , Pez CebraRESUMEN
The cellular concentration of Bcl-xL is among the most important determinants of treatment response and overall prognosis in a broad range of tumors as well as an important determinant of the cellular response to several forms of tissue injury. We and others have previously shown that human Bcl-xL undergoes deamidation at two asparaginyl residues and that DNA-damaging antineoplastic agents as well as other stimuli can increase the rate of deamidation. Deamidation results in the replacement of asparginyl residues with aspartyl or isoaspartyl residues. Thus deamidation, like phosphorylation, introduces a negative charge into proteins. Here we show that the level of human Bcl-xL is constantly modulated by deamidation because deamidation, like phosphorylation in other proteins, activates a conditional PEST sequence to target Bcl-xL for degradation. Additionally, we show that degradation of deamidated Bcl-xL is mediated at least in part by calpain. Notably, we present sequence and biochemical data that suggest that deamidation has been conserved from the simplest extant metazoans through the human form of Bcl-xL, underscoring its importance in Bcl-xL regulation. Our findings strongly suggest that deamidation-regulated Bcl-xL degradation is an important component of the cellular rheostat that determines susceptibility to DNA-damaging agents and other death stimuli.
Asunto(s)
Amidas/metabolismo , Proteolisis , Proteína bcl-X/metabolismo , Secuencia de Aminoácidos , Animales , Calpaína/metabolismo , Línea Celular , Secuencia Conservada , Daño del ADN , Humanos , Concentración de Iones de Hidrógeno , Ratones , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Proteína bcl-X/químicaRESUMEN
Broadening gene therapy applications requires manufacturable vectors that efficiently transduce target cells in humans and preclinical models. Conventional selections of adeno-associated virus (AAV) capsid libraries are inefficient at searching the vast sequence space for the small fraction of vectors possessing multiple traits essential for clinical translation. Here, we present Fit4Function, a generalizable machine learning (ML) approach for systematically engineering multi-trait AAV capsids. By leveraging a capsid library that uniformly samples the manufacturable sequence space, reproducible screening data are generated to train accurate sequence-to-function models. Combining six models, we designed a multi-trait (liver-targeted, manufacturable) capsid library and validated 88% of library variants on all six predetermined criteria. Furthermore, the models, trained only on mouse in vivo and human in vitro Fit4Function data, accurately predicted AAV capsid variant biodistribution in macaque. Top candidates exhibited production yields comparable to AAV9, efficient murine liver transduction, up to 1000-fold greater human hepatocyte transduction, and increased enrichment relative to AAV9 in a screen for liver transduction in macaques. The Fit4Function strategy ultimately makes it possible to predict cross-species traits of peptide-modified AAV capsids and is a critical step toward assembling an ML atlas that predicts AAV capsid performance across dozens of traits.
Asunto(s)
Proteínas de la Cápside , Cápside , Dependovirus , Vectores Genéticos , Hígado , Dependovirus/genética , Animales , Humanos , Ratones , Vectores Genéticos/genética , Cápside/metabolismo , Proteínas de la Cápside/genética , Proteínas de la Cápside/metabolismo , Hígado/metabolismo , Transducción Genética , Técnicas de Transferencia de Gen , Aprendizaje Automático , Terapia Genética/métodos , Macaca , Hepatocitos/metabolismo , Células HEK293 , Ingeniería Genética/métodosRESUMEN
Prion disease is caused by misfolding of the prion protein (PrP) into pathogenic self-propagating conformations, leading to rapid-onset dementia and death. However, elimination of endogenous PrP halts prion disease progression. In this study, we describe Coupled Histone tail for Autoinhibition Release of Methyltransferase (CHARM), a compact, enzyme-free epigenetic editor capable of silencing transcription through programmable DNA methylation. Using a histone H3 tail-Dnmt3l fusion, CHARM recruits and activates endogenous DNA methyltransferases, thereby reducing transgene size and cytotoxicity. When delivered to the mouse brain by systemic injection of adeno-associated virus (AAV), Prnp-targeted CHARM ablates PrP expression across the brain. Furthermore, we have temporally limited editor expression by implementing a kinetically tuned self-silencing approach. CHARM potentially represents a broadly applicable strategy to suppress pathogenic proteins, including those implicated in other neurodegenerative diseases.
Asunto(s)
Encéfalo , Metilación de ADN , Dependovirus , Silenciador del Gen , Histonas , Proteínas Priónicas , Animales , Humanos , Ratones , Encéfalo/metabolismo , Dependovirus/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , Histonas/metabolismo , Enfermedades por Prión/genética , Enfermedades por Prión/metabolismo , Proteínas Priónicas/genética , Proteínas Priónicas/metabolismo , TransgenesRESUMEN
Developing vehicles that efficiently deliver genes throughout the human central nervous system (CNS) will broaden the range of treatable genetic diseases. We engineered an adeno-associated virus (AAV) capsid, BI-hTFR1, that binds human transferrin receptor (TfR1), a protein expressed on the blood-brain barrier. BI-hTFR1 was actively transported across human brain endothelial cells and, relative to AAV9, provided 40 to 50 times greater reporter expression in the CNS of human TFRC knockin mice. The enhanced tropism was CNS-specific and absent in wild-type mice. When used to deliver GBA1, mutations of which cause Gaucher disease and are linked to Parkinson's disease, BI-hTFR1 substantially increased brain and cerebrospinal fluid glucocerebrosidase activity compared with AAV9. These findings establish BI-hTFR1 as a potential vector for human CNS gene therapy.
Asunto(s)
Antígenos CD , Encéfalo , Cápside , Técnicas de Transferencia de Gen , Vectores Genéticos , Glucosilceramidasa , Receptores de Transferrina , Animales , Humanos , Ratones , Antígenos CD/metabolismo , Antígenos CD/genética , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Cápside/metabolismo , Proteínas de la Cápside/metabolismo , Proteínas de la Cápside/genética , Dependovirus , Células Endoteliales/metabolismo , Técnicas de Sustitución del Gen , Terapia Genética , Receptores de Transferrina/metabolismo , Receptores de Transferrina/genética , Glucosilceramidasa/genética , Enfermedad de Gaucher/genética , Enfermedad de Gaucher/terapia , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/terapiaRESUMEN
New CNS neurons and glia are generated throughout adulthood from endogenous neural stem and progenitor cells. These progenitors can respond to injury, but their ability to proliferate, migrate, differentiate, and survive is usually insufficient to replace lost cells and restore normal function. Potentiating the progenitor response with exogenous factors is an attractive strategy for the treatment of nervous system injuries and neurodegenerative and demyelinating disorders. Previously, we reported that delivery of leukemia inhibitory factor (LIF) to the CNS stimulates the self-renewal of neural stem cells and the proliferation of parenchymal glial progenitors. Here we identify these parenchymal glia as oligodendrocyte (OL) progenitor cells (OPCs) and show that LIF delivery stimulates their proliferation through the activation of gp130 receptor signaling within these cells. Importantly, this effect of LIF on OPC proliferation can be harnessed to enhance the generation of OLs that express myelin proteins and reform nodes of Ranvier in the context of chronic demyelination in the adult mouse hippocampus. Our findings, considered together with the known beneficial effects of LIF on OL and neuron survival, suggest that LIF has both reparative and protective activities that make it a promising potential therapy for CNS demyelinating disorders and injuries.
Asunto(s)
Proliferación Celular , Hipocampo/fisiología , Factor Inhibidor de Leucemia/fisiología , Vaina de Mielina/metabolismo , Oligodendroglía/fisiología , Células Madre/fisiología , Animales , Proliferación Celular/efectos de los fármacos , Femenino , Hipocampo/citología , Hipocampo/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Ratones Transgénicos , Vaina de Mielina/patología , Neurogénesis/fisiología , Oligodendroglía/patología , Nódulos de Ranvier/patología , Nódulos de Ranvier/fisiología , Células Madre/patologíaRESUMEN
Developing vehicles that efficiently deliver genes throughout the human central nervous system (CNS) will broaden the range of treatable genetic diseases. We engineered an AAV capsid, BI-hTFR1, that binds human Transferrin Receptor (TfR1), a protein expressed on the blood-brain barrier (BBB). BI-hTFR1 was actively transported across a human brain endothelial cell layer and, relative to AAV9, provided 40-50 times greater reporter expression in the CNS of human TFRC knock-in mice. The enhanced tropism was CNS-specific and absent in wild type mice. When used to deliver GBA1, mutations of which cause Gaucher disease and are linked to Parkinson's disease, BI-hTFR1 substantially increased brain and cerebrospinal fluid glucocerebrosidase activity compared to AAV9. These findings establish BI-hTFR1 as a promising vector for human CNS gene therapy.
RESUMEN
Adeno-associated viruses (AAVs) promise robust gene delivery to the brain through non-invasive, intravenous delivery. However, unlike in rodents, few neurotropic AAVs efficiently cross the blood-brain barrier in non-human primates (NHPs). Here we describe AAV.CAP-Mac, an engineered variant identified by screening in adult marmosets and newborn macaques with improved efficiency in the brain of multiple NHP species: marmoset, rhesus macaque, and green monkey. CAP-Mac is neuron-biased in infant Old World primates, exhibits broad tropism in adult rhesus macaques, and is vasculature-biased in adult marmosets. We demonstrate applications of a single, intravenous dose of CAP-Mac to deliver (1) functional GCaMP for ex vivo calcium imaging across multiple brain areas, and (2) a cocktail of fluorescent reporters for Brainbow-like labeling throughout the macaque brain, circumventing the need for germline manipulations in Old World primates. Given its capabilities for systemic gene transfer in NHPs, CAP-Mac promises to help unlock non-invasive access to the brain.
RESUMEN
The mammalian brain is composed of many brain structures, each with its own ontogenetic and developmental history. We used single-nucleus RNA sequencing to sample over 2.4 million brain cells across 18 locations in the common marmoset, a New World monkey primed for genetic engineering, and examined gene expression patterns of cell types within and across brain structures. The adult transcriptomic identity of most neuronal types is shaped more by developmental origin than by neurotransmitter signaling repertoire. Quantitative mapping of GABAergic types with single-molecule FISH (smFISH) reveals that interneurons in the striatum and neocortex follow distinct spatial principles, and that lateral prefrontal and other higher-order cortical association areas are distinguished by high proportions of VIP+ neurons. We use cell type-specific enhancers to drive AAV-GFP and reconstruct the morphologies of molecularly resolved interneuron types in neocortex and striatum. Our analyses highlight how lineage, local context, and functional class contribute to the transcriptional identity and biodistribution of primate brain cell types.
Asunto(s)
Callithrix , Neocórtex , Animales , Neocórtex/fisiología , Neuronas/fisiología , Distribución TisularRESUMEN
Crossing the blood-brain barrier in primates is a major obstacle for gene delivery to the brain. Adeno-associated viruses (AAVs) promise robust, non-invasive gene delivery from the bloodstream to the brain. However, unlike in rodents, few neurotropic AAVs efficiently cross the blood-brain barrier in non-human primates. Here we report on AAV.CAP-Mac, an engineered variant identified by screening in adult marmosets and newborn macaques, which has improved delivery efficiency in the brains of multiple non-human primate species: marmoset, rhesus macaque and green monkey. CAP-Mac is neuron biased in infant Old World primates, exhibits broad tropism in adult rhesus macaques and is vasculature biased in adult marmosets. We demonstrate applications of a single, intravenous dose of CAP-Mac to deliver functional GCaMP for ex vivo calcium imaging across multiple brain areas, or a cocktail of fluorescent reporters for Brainbow-like labelling throughout the macaque brain, circumventing the need for germline manipulations in Old World primates. As such, CAP-Mac is shown to have potential for non-invasive systemic gene transfer in the brains of non-human primates.
Asunto(s)
Encéfalo , Callithrix , Humanos , Animales , Recién Nacido , Chlorocebus aethiops , Macaca mulatta/genética , Callithrix/genética , Encéfalo/fisiología , Técnicas de Transferencia de Gen , Neuronas , Vectores Genéticos/genéticaRESUMEN
The discovery two decades ago that the Philadelphia chromosome encodes an oncogenic fusion of Bcr and Abl remains among the most important contributions to our understanding of the process of malignant transformation. We now know that Bcr-Abl is one of more than 30 aberrantly activated tyrosine kinases that are expressed in a variety of tumors. Conventional treatment of the tumors in which these proteins are expressed is usually doomed to failure because the activated tyrosine kinases render the tumor cells stubbornly resistant to apoptosis. In this context, it is notable that Zhao and coworkers have uncovered a novel weapon in the resistance armamentarium of these rogue kinases, the suppression of the inactivating deamidation of Bcl-xL (this issue of Cancer Cell).