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Kohlschütter-Tönz syndrome (KTS) is a rare autosomal recessive disorder characterized by severe intellectual disability, early-onset epileptic seizures, and amelogenesis imperfecta. Here, we present a novel Rogdi mutant mouse deleting exons 6-11- a mutation found in KTS patients disabling ROGDI function. This Rogdi-/- mutant model recapitulates most KTS symptoms. Mutants displayed pentylenetetrazol-induced seizures, confirming epilepsy susceptibility. Spontaneous locomotion and circadian activity tests demonstrate Rogdi mutant hyperactivity mirroring patient spasticity. Object recognition impairment indicates memory deficits. Rogdi-/- mutant enamel was markedly less mature. Scanning electron microscopy confirmed its hypomineralized/hypomature crystallization, as well as its low mineral content. Transcriptomic RNA sequencing of postnatal day 5 lower incisors showed downregulated enamel matrix proteins Enam, Amelx, and Ambn. Enamel crystallization appears highly pH-dependent, cycling between an acidic and neutral pH during enamel maturation. Rogdi-/- teeth exhibit no signs of cyclic dental acidification. Additionally, expression changes in Wdr72, Slc9a3r2, and Atp6v0c were identified as potential contributors to these tooth acidification abnormalities. These proteins interact through the acidifying V-ATPase complex. Here, we present the Rogdi-/- mutant as a novel model to partially decipher KTS pathophysiology. Rogdi-/- mutant defects in acidification might explain the unusual combination of enamel and rare neurological disease symptoms.
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Amelogénesis Imperfecta , Demencia , Epilepsia , Anomalías Dentarias , Humanos , Animales , Ratones , Amelogénesis Imperfecta/genética , Convulsiones , Mutación , Proteínas de la Membrana/genética , Proteínas Nucleares/genéticaRESUMEN
BACKGROUND: Using mouse genetic studies and systematic assessments of brain neuroanatomical phenotypes, we set out to identify which of the 30 genes causes brain defects at the autism-associated 16p11.2 locus. RESULTS: We show that multiple genes mapping to this region interact to regulate brain anatomy, with female mice exhibiting far fewer brain neuroanatomical phenotypes. In male mice, among the 13 genes associated with neuroanatomical defects (Mvp, Ppp4c, Zg16, Taok2, Slx1b, Maz, Fam57b, Bola2, Tbx6, Qprt, Spn, Hirip3, and Doc2a), Mvp is the top driver implicated in phenotypes pertaining to brain, cortex, hippocampus, ventricles, and corpus callosum sizes. The major vault protein (MVP), the main component of the vault organelle, is a conserved protein found in eukaryotic cells, yet its function is not understood. Here, we find MVP expression highly specific to the limbic system and show that Mvp regulates neuronal morphology, postnatally and specifically in males. We also recapitulate a previously reported genetic interaction and show that Mvp+/-;Mapk3+/- mice exhibit behavioral deficits, notably decreased anxiety-like traits detected in the elevated plus maze and open field paradigms. CONCLUSIONS: Our study highlights multiple gene drivers in neuroanatomical phenotypes, interacting with each other through complex relationships. It also provides the first evidence for the involvement of the major vault protein in the regulation of brain size and neuroanatomy, specifically in male mice.
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Trastorno Autístico , Masculino , Animales , Ratones , Femenino , Trastorno Autístico/genética , Trastorno Autístico/metabolismo , Neuroanatomía , Encéfalo/metabolismo , Fenotipo , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas de Unión al Calcio/genética , Proteínas del Tejido Nervioso/metabolismoRESUMEN
Dynein heavy chain (DYNC1H1) mutations can either lead to severe cerebral cortical malformations, or alternatively may be associated with the development of spinal muscular atrophy with lower extremity predominance (SMA-LED). To assess the origin of such differences, we studied a new Dync1h1 knock-in mouse carrying the cortical malformation p.Lys3334Asn mutation. Comparing with an existing neurodegenerative Dync1h1 mutant (Legs at odd angles, Loa, p.Phe580Tyr/+), we assessed Dync1h1's roles in cortical progenitor and especially radial glia functions during embryogenesis, and assessed neuronal differentiation. p.Lys3334Asn /+ mice exhibit reduced brain and body size. Embryonic brains show increased and disorganized radial glia: interkinetic nuclear migration occurs in mutants, however there are increased basally positioned cells and abventricular mitoses. The ventricular boundary is disorganized potentially contributing to progenitor mislocalization and death. Morphologies of mitochondria and Golgi apparatus are perturbed in vitro, with different effects also in Loa mice. Perturbations of neuronal migration and layering are also observed in p.Lys3334Asn /+ mutants. Overall, we identify specific developmental effects due to a severe cortical malformation mutation in Dync1h1, highlighting the differences with a mutation known instead to primarily affect motor function.
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Dineínas , Atrofia Muscular Espinal , Humanos , Ratones , Animales , Dineínas/genética , Dineínas Citoplasmáticas/genética , Dineínas Citoplasmáticas/metabolismo , Atrofia Muscular Espinal/genética , Tamaño de los Órganos , Mutación/genética , Encéfalo/metabolismo , Células MadreRESUMEN
Major progress has been made over the last decade in identifying novel genes involved in neurodevelopmental disorders, although the task of elucidating their corresponding molecular and pathophysiological mechanisms, which are an essential prerequisite for developing therapies, has fallen far behind. We selected 45 genes for intellectual disabilities to generate and characterize mouse models. Thirty-nine of them were based on the frequency of pathogenic variants in patients and literature reports, with several corresponding to de novo variants, and six other candidate genes. We used an extensive screen covering the development and adult stages, focusing specifically on behaviour and cognition to assess a wide range of functions and their pathologies, ranging from basic neurological reflexes to cognitive abilities. A heatmap of behaviour phenotypes was established, together with the results of selected mutants. Overall, three main classes of mutant lines were identified based on activity phenotypes, with which other motor or cognitive deficits were associated. These data showed the heterogeneity of phenotypes between mutation types, recapitulating several human features, and emphasizing the importance of such systematic approaches for both deciphering genetic etiological causes of ID and autism spectrum disorders, and for building appropriate therapeutic strategies.
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Intellectual disabilities (ID) constitute a class of human neurodevelopmental diseases and are a major medical and socioeconomic problem owing to their high incidence and enormous burden to the families of those affected. In the past three decades, mutant mouse technologies have provided powerful tools for elucidating the pathophysiological mechanisms underlying behavioral and developmental alterations related to IDs and for addressing new therapeutic strategies, and major progress has been made revealing previously unidentified genes involved in ID. However, the pathological hallmarks of IDs are very heterogeneous in regard to both the functional deficits observed and the severity of the phenotype, even within the same mutation types. For this reason, an appropriate experimental design is required to reduce the risk of false negatives and positives in animal functional genomic studies. This experimental design should address functions important to evaluate, tests, and the appropriate workflow. Here, we propose an extensive behavioral screen with detailed protocols, which was successfully used in a systematic mouse functional genomic approach to gain pathway-based insights into mechanisms leading to cognitive dysfunction in humans. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Assessment of circadian activity and ingestive behavior Basic Protocol 2: Assessment of neurological reflexes and motor abilities using the grip and rotarod tests Basic Protocol 3: Evaluation of anxiety-related behavior using the elevated plus maze Basic Protocol 4: Evaluation of recognition memory using the object recognition task Basic Protocol 5: Evaluation of social behavior using the social recognition test Basic Protocol 6: Evaluation of working memory using the Y-maze spontaneous alternation test Basic Protocol 7: Evaluation of emotional learning and memory using the fear conditioning test.
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Miedo , Conducta Social , Animales , Ansiedad , Cognición , Ratones , FenotipoRESUMEN
Improving reproducibility and replicability in preclinical research is a widely discussed and pertinent topic, especially regarding ethical responsibility in animal research. INFRAFRONTIER, the European Research Infrastructure for the generation, phenotyping, archiving, and distribution of model mammalian genomes, is addressing this issue by developing internal quality principles for its different service areas, that provides a quality framework for its operational activities. This article introduces the INFRAFRONTIER Quality Principles in Systemic Phenotyping of genetically altered mouse models. A total of 11 key principles are included, ranging from general requirements for compliance with guidelines on animal testing, to the need for well-trained personnel and more specific standards such as the exchange of reference lines. Recently established requirements such as the provision of FAIR (Findable, Accessible, Interoperable, Reusable) data are also addressed. For each quality principle, we have outlined the specific context, requirements, further recommendations, and key references.
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Genoma , Mamíferos , Animales , Modelos Animales de Enfermedad , Ratones , Reproducibilidad de los ResultadosRESUMEN
Genes are pleiotropic and getting a better knowledge of their function requires a comprehensive characterization of their mutants. Here, we generated multi-level data combining phenomic, proteomic and metabolomic acquisitions from plasma and liver tissues of two C57BL/6 N mouse models lacking the Lat (linker for activation of T cells) and the Mx2 (MX dynamin-like GTPase 2) genes, respectively. Our dataset consists of 9 assays (1 preclinical, 2 proteomics and 6 metabolomics) generated with a fully non-targeted and standardized approach. The data and processing code are publicly available in the ProMetIS R package to ensure accessibility, interoperability, and reusability. The dataset thus provides unique molecular information about the physiological role of the Lat and Mx2 genes. Furthermore, the protocols described herein can be easily extended to a larger number of individuals and tissues. Finally, this resource will be of great interest to develop new bioinformatic and biostatistic methods for multi-omics data integration.
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Modelos Animales de Enfermedad , Metabolómica , Proteómica , Proteínas Adaptadoras Transductoras de Señales , Animales , Femenino , Hígado , Masculino , Proteínas de la Membrana , Ratones , Ratones Endogámicos C57BL , Proteínas de Resistencia a Mixovirus , Fenotipo , PlasmaRESUMEN
Perturbation of the excitation/inhibition (E/I) balance leads to neurodevelopmental diseases including to autism spectrum disorders, intellectual disability, and epilepsy. Loss-of-function mutations in the DYRK1A gene, located on human chromosome 21 (Hsa21,) lead to an intellectual disability syndrome associated with microcephaly, epilepsy, and autistic troubles. Overexpression of DYRK1A, on the other hand, has been linked with learning and memory defects observed in people with Down syndrome (DS). Dyrk1a is expressed in both glutamatergic and GABAergic neurons, but its impact on each neuronal population has not yet been elucidated. Here we investigated the impact of Dyrk1a gene copy number variation in glutamatergic neurons using a conditional knockout allele of Dyrk1a crossed with the Tg(Camk2-Cre)4Gsc transgenic mouse. We explored this genetic modification in homozygotes, heterozygotes and combined with the Dp(16Lipi-Zbtb21)1Yey trisomic mouse model to unravel the consequence of Dyrk1a dosage from 0 to 3, to understand its role in normal physiology, and in MRD7 and DS. Overall, Dyrk1a dosage in postnatal glutamatergic neurons did not impact locomotor activity, working memory or epileptic susceptibility, but revealed that Dyrk1a is involved in long-term explicit memory. Molecular analyses pointed at a deregulation of transcriptional activity through immediate early genes and a role of DYRK1A at the glutamatergic post-synapse by deregulating and interacting with key post-synaptic proteins implicated in mechanism leading to long-term enhanced synaptic plasticity. Altogether, our work gives important information to understand the action of DYRK1A inhibitors and have a better therapeutic approach.
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Trastorno Autístico/genética , Trastornos del Conocimiento/genética , Síndrome de Down/genética , Dosificación de Gen , Ácido Glutámico/metabolismo , Discapacidad Intelectual/genética , Neuronas/metabolismo , Trastornos del Habla/genética , Animales , Encéfalo/patología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Trastornos del Conocimiento/complicaciones , Modelos Animales de Enfermedad , Síndrome de Down/complicaciones , Regulación de la Expresión Génica , Humanos , Ratones , Ratones Transgénicos , Proteómica/métodos , Transmisión Sináptica/genética , Transcripción GenéticaRESUMEN
The genetic landscape of diseases associated with changes in bone mineral density (BMD), such as osteoporosis, is only partially understood. Here, we explored data from 3,823 mutant mouse strains for BMD, a measure that is frequently altered in a range of bone pathologies, including osteoporosis. A total of 200 genes were found to significantly affect BMD. This pool of BMD genes comprised 141 genes with previously unknown functions in bone biology and was complementary to pools derived from recent human studies. Nineteen of the 141 genes also caused skeletal abnormalities. Examination of the BMD genes in osteoclasts and osteoblasts underscored BMD pathways, including vesicle transport, in these cells and together with in silico bone turnover studies resulted in the prioritization of candidate genes for further investigation. Overall, the results add novel pathophysiological and molecular insight into bone health and disease.
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Densidad Ósea/genética , Regulación de la Expresión Génica/genética , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteoporosis/genética , Animales , Femenino , Ontología de Genes , Pleiotropía Genética , Estudio de Asociación del Genoma Completo , Genotipo , Masculino , Ratones , Ratones Transgénicos , Mutación , Osteoblastos/patología , Osteoclastos/patología , Osteoporosis/metabolismo , Fenotipo , Regiones Promotoras Genéticas , Mapas de Interacción de Proteínas , Caracteres Sexuales , TranscriptomaRESUMEN
BAHD1 is a heterochomatinization factor recently described as a component of a multiprotein complex associated with histone deacetylases HDAC1/2. The physiological and patho-physiological functions of BAHD1 are not yet well characterized. Here, we examined the consequences of BAHD1 deficiency in the brains of male mice. While Bahd1 knockout mice had no detectable defects in brain anatomy, RNA sequencing profiling revealed about 2500 deregulated genes in Bahd1-/- brains compared to Bahd1+/+ brains. A majority of these genes were involved in nervous system development and function, behavior, metabolism and immunity. Exploration of the Allen Brain Atlas and Dropviz databases, assessing gene expression in the brain, revealed that expression of the Bahd1 gene was limited to a few territories and cell subtypes, particularly in the hippocampal formation, the isocortex and the olfactory regions. The effect of partial BAHD1 deficiency on behavior was then evaluated on Bahd1 heterozygous male mice, which have no lethal or metabolic phenotypes. Bahd1+/- mice showed anxiety-like behavior and reduced prepulse inhibition (PPI) of the startle response. Altogether, these results suggest that BAHD1 plays a role in chromatin-dependent gene regulation in a subset of brain cells and support recent evidence linking genetic alteration of BAHD1 to psychiatric disorders in a human patient.
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Ansiedad/genética , Encéfalo/metabolismo , Proteínas Cromosómicas no Histona/genética , Reflejo de Sobresalto/genética , Animales , Ansiedad/fisiopatología , Encéfalo/patología , Cromatina/genética , Regulación de la Expresión Génica/genética , Haploinsuficiencia/genética , Histona Desacetilasa 1/genética , Histona Desacetilasa 2/genética , Humanos , Ratones , Ratones Noqueados , Fenotipo , Análisis de Secuencia de ARNRESUMEN
MOTIVATION: High-throughput phenomic projects generate complex data from small treatment and large control groups that increase the power of the analyses but introduce variation over time. A method is needed to utlize a set of temporally local controls that maximizes analytic power while minimizing noise from unspecified environmental factors. RESULTS: Here we introduce 'soft windowing', a methodological approach that selects a window of time that includes the most appropriate controls for analysis. Using phenotype data from the International Mouse Phenotyping Consortium (IMPC), adaptive windows were applied such that control data collected proximally to mutants were assigned the maximal weight, while data collected earlier or later had less weight. We applied this method to IMPC data and compared the results with those obtained from a standard non-windowed approach. Validation was performed using a resampling approach in which we demonstrate a 10% reduction of false positives from 2.5 million analyses. We applied the method to our production analysis pipeline that establishes genotype-phenotype associations by comparing mutant versus control data. We report an increase of 30% in significant P-values, as well as linkage to 106 versus 99 disease models via phenotype overlap with the soft-windowed and non-windowed approaches, respectively, from a set of 2082 mutant mouse lines. Our method is generalizable and can benefit large-scale human phenomic projects such as the UK Biobank and the All of Us resources. AVAILABILITY AND IMPLEMENTATION: The method is freely available in the R package SmoothWin, available on CRAN http://CRAN.R-project.org/package=SmoothWin. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Salud Poblacional , Programas Informáticos , Animales , Estudios de Asociación Genética , Humanos , Ratones , FenotipoRESUMEN
The cerebral cortex is a highly organized structure responsible for advanced cognitive functions. Its development relies on a series of steps including neural progenitor cell proliferation, neuronal migration, axonal outgrowth and brain wiring. Disruption of these steps leads to cortical malformations, often associated with intellectual disability and epilepsy. We have generated a new resource to shed further light on subcortical heterotopia, a malformation characterized by abnormal neuronal position. We describe here the generation and characterization of a knockout (KO) mouse model for Eml1, a microtubule-associated protein showing mutations in human ribbon-like subcortical heterotopia. As previously reported for a spontaneous mouse mutant showing a mutation in Eml1, we observe severe cortical heterotopia in the KO. We also observe abnormal progenitor cells in early corticogenesis, likely to be the origin of the defects. EML1 KO mice on the C57BL/6N genetic background also appear to present a wider phenotype than the original mouse mutant, showing additional brain anomalies, such as corpus callosum abnormalities. We compare the anatomy of male and female mice and also study heterozygote animals. This new resource will help unravel roles for Eml1 in brain development and tissue architecture, as well as the mechanisms leading to severe subcortical heterotopia.
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Encéfalo/patología , Lisencefalias Clásicas y Heterotopias Subcorticales en Banda/patología , Proteínas Asociadas a Microtúbulos/fisiología , Animales , Lisencefalias Clásicas y Heterotopias Subcorticales en Banda/embriología , Lisencefalias Clásicas y Heterotopias Subcorticales en Banda/genética , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones NoqueadosRESUMEN
The aristaless-related homeobox (ARX) transcription factor is involved in the development of GABAergic and cholinergic neurons in the forebrain. ARX mutations have been associated with a wide spectrum of neurodevelopmental disorders in humans, among which the most frequent, a 24 bp duplication in the polyalanine tract 2 (c.428_451dup24), gives rise to intellectual disability, fine motor defects with or without epilepsy. To understand the functional consequences of this mutation, we generated a partially humanized mouse model carrying the c.428_451dup24 duplication (Arxdup24/0) that we characterized at the behavior, neurological and molecular level. Arxdup24/0 males presented with hyperactivity, enhanced stereotypies and altered contextual fear memory. In addition, Arxdup24/0 males had fine motor defects with alteration of reaching and grasping abilities. Transcriptome analysis of Arxdup24/0 forebrains at E15.5 showed a down-regulation of genes specific to interneurons and an up-regulation of genes normally not expressed in this cell type, suggesting abnormal interneuron development. Accordingly, interneuron migration was altered in the cortex and striatum between E15.5 and P0 with consequences in adults, illustrated by the defect in the inhibitory/excitatory balance in Arxdup24/0 basolateral amygdala. Altogether, we showed that the c.428_451dup24 mutation disrupts Arx function with a direct consequence on interneuron development, leading to hyperactivity and defects in precise motor movement control and associative memory. Interestingly, we highlighted striking similarities between the mouse phenotype and a cohort of 33 male patients with ARX c.428_451dup24, suggesting that this new mutant mouse line is a good model for understanding the pathophysiology and evaluation of treatment.
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Epilepsia/genética , Proteínas de Homeodominio/genética , Trastornos del Neurodesarrollo/genética , Factores de Transcripción/genética , Adolescente , Adulto , Animales , Niño , Preescolar , Neuronas Colinérgicas/metabolismo , Neuronas Colinérgicas/patología , Contractura , Modelos Animales de Enfermedad , Epilepsia/fisiopatología , Neuronas GABAérgicas/metabolismo , Neuronas GABAérgicas/patología , Regulación del Desarrollo de la Expresión Génica , Humanos , Lactante , Discapacidad Intelectual , Masculino , Ratones , Mutación , Trastornos del Neurodesarrollo/fisiopatología , Péptidos/genética , Prosencéfalo/fisiopatología , Paraplejía Espástica Hereditaria , Transcriptoma/genética , Adulto JovenRESUMEN
Kleefstra syndrome, a disease with intellectual disability, autism spectrum disorders and other developmental defects is caused in humans by haploinsufficiency of EHMT1. Although EHMT1 and its paralog EHMT2 were shown to be histone methyltransferases responsible for deposition of the di-methylated H3K9 (H3K9me2), the exact nature of epigenetic dysfunctions in Kleefstra syndrome remains unknown. Here, we found that the epigenome of Ehmt1+/- adult mouse brain displays a marked increase of H3K9me2/3 which correlates with impaired expression of protocadherins, master regulators of neuronal diversity. Increased H3K9me3 was present already at birth, indicating that aberrant methylation patterns are established during embryogenesis. Interestingly, we found that Ehmt2+/- mice do not present neither the marked increase of H3K9me2/3 nor the cognitive deficits found in Ehmt1+/- mice, indicating an evolutionary diversification of functions. Our finding of increased H3K9me3 in Ehmt1+/- mice is the first one supporting the notion that EHMT1 can quench the deposition of tri-methylation by other Histone methyltransferases, ultimately leading to impaired neurocognitive functioning. Our insights into the epigenetic pathophysiology of Kleefstra syndrome may offer guidance for future developments of therapeutic strategies for this disease.
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Cadherinas/genética , Disfunción Cognitiva/metabolismo , Anomalías Craneofaciales/metabolismo , Cardiopatías Congénitas/metabolismo , Histonas/metabolismo , Discapacidad Intelectual/metabolismo , Animales , Animales Recién Nacidos , Cadherinas/metabolismo , Deleción Cromosómica , Cromosomas Humanos Par 9/metabolismo , Disfunción Cognitiva/genética , Anomalías Craneofaciales/psicología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Cardiopatías Congénitas/psicología , Hipocampo/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , Discapacidad Intelectual/psicología , Lisina/metabolismo , Masculino , Metilación , Ratones NoqueadosRESUMEN
This corrects the article DOI: 10.1038/nature19356.
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Koolen-de Vries syndrome (KdVS) is a multi-system disorder characterized by intellectual disability, friendly behavior, and congenital malformations. The syndrome is caused either by microdeletions in the 17q21.31 chromosomal region or by variants in the KANSL1 gene. The reciprocal 17q21.31 microduplication syndrome is associated with psychomotor delay, and reduced social interaction. To investigate the pathophysiology of 17q21.31 microdeletion and microduplication syndromes, we generated three mouse models: 1) the deletion (Del/+); or 2) the reciprocal duplication (Dup/+) of the 17q21.31 syntenic region; and 3) a heterozygous Kansl1 (Kans1+/-) model. We found altered weight, general activity, social behaviors, object recognition, and fear conditioning memory associated with craniofacial and brain structural changes observed in both Del/+ and Dup/+ animals. By investigating hippocampus function, we showed synaptic transmission defects in Del/+ and Dup/+ mice. Mutant mice with a heterozygous loss-of-function mutation in Kansl1 displayed similar behavioral and anatomical phenotypes compared to Del/+ mice with the exception of sociability phenotypes. Genes controlling chromatin organization, synaptic transmission and neurogenesis were upregulated in the hippocampus of Del/+ and Kansl1+/- animals. Our results demonstrate the implication of KANSL1 in the manifestation of KdVS phenotypes and extend substantially our knowledge about biological processes affected by these mutations. Clear differences in social behavior and gene expression profiles between Del/+ and Kansl1+/- mice suggested potential roles of other genes affected by the 17q21.31 deletion. Together, these novel mouse models provide new genetic tools valuable for the development of therapeutic approaches.
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Anomalías Múltiples/genética , Duplicación Cromosómica/genética , Cognición , Discapacidad Intelectual/genética , Proteínas Nucleares/genética , Animales , Peso Corporal , Encéfalo/metabolismo , Encéfalo/ultraestructura , Deleción Cromosómica , Estructuras Cromosómicas/genética , Estructuras Cromosómicas/metabolismo , Cromosomas Humanos Par 17/genética , Variaciones en el Número de Copia de ADN , Modelos Animales de Enfermedad , Epigénesis Genética , Femenino , Eliminación de Gen , Reordenamiento Génico , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Plasticidad Neuronal/genética , Proteínas Nucleares/metabolismo , Transmisión Sináptica/genética , Regulación hacia ArribaRESUMEN
Approximately one-third of all mammalian genes are essential for life. Phenotypes resulting from knockouts of these genes in mice have provided tremendous insight into gene function and congenital disorders. As part of the International Mouse Phenotyping Consortium effort to generate and phenotypically characterize 5,000 knockout mouse lines, here we identify 410 lethal genes during the production of the first 1,751 unique gene knockouts. Using a standardized phenotyping platform that incorporates high-resolution 3D imaging, we identify phenotypes at multiple time points for previously uncharacterized genes and additional phenotypes for genes with previously reported mutant phenotypes. Unexpectedly, our analysis reveals that incomplete penetrance and variable expressivity are common even on a defined genetic background. In addition, we show that human disease genes are enriched for essential genes, thus providing a dataset that facilitates the prioritization and validation of mutations identified in clinical sequencing efforts.
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Embrión de Mamíferos/embriología , Embrión de Mamíferos/metabolismo , Genes Esenciales/genética , Genes Letales/genética , Mutación/genética , Fenotipo , Animales , Secuencia Conservada/genética , Enfermedad , Estudio de Asociación del Genoma Completo , Ensayos Analíticos de Alto Rendimiento , Humanos , Imagenología Tridimensional , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Penetrancia , Polimorfismo de Nucleótido Simple/genética , Homología de SecuenciaRESUMEN
Loss of function mutations in human Oligophrenin1 (OPHN1) gene are responsible for syndromic intellectual disability (ID) associated with cerebellar hypoplasia and cerebral ventricles enlargement. Functional studies in rodent models suggest that OPHN1 linked ID is a consequence of abnormal synaptic transmission and shares common pathophysiological mechanisms with other cognitive disorders. Variants of this gene have been also identified in autism spectrum disorder and schizophrenia. The advanced understanding of the mechanisms underlying OPHN1-related ID, allowed us to develop a therapeutic approach targeting the Ras homolog gene family, member A (RHOA) signalling pathway and repurpose Fasudil- a well-tolerated Rho Kinase (ROCK) and Protein Kinase A (PKA) inhibitor- as a treatment of ID. We have previously shown ex-vivo its beneficial effect on synaptic transmission and plasticity in a mouse model of the OPHN1 loss of function. Here, we report that chronic treatment in adult mouse with Fasudil, is able to counteract vertical and horizontal hyperactivities, restores recognition memory and limits the brain ventricular dilatation observed in Ophn1-/y However, deficits in working and spatial memories are partially or not rescued by the treatment. These results highlight the potential of Fasudil treatment in synaptopathies and also the need for multiple therapeutic approaches especially in adult where brain plasticity is reduced.
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1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , Encéfalo/fisiopatología , Proteínas del Citoesqueleto/genética , Proteínas Activadoras de GTPasa/genética , Discapacidad Intelectual/tratamiento farmacológico , Proteínas Nucleares/genética , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/administración & dosificación , Adulto , Animales , Trastorno del Espectro Autista , Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Modelos Animales de Enfermedad , Humanos , Discapacidad Intelectual/genética , Discapacidad Intelectual/fisiopatología , Ratones , Transmisión SinápticaRESUMEN
ATP6AP2, an essential accessory component of the vacuolar H+ ATPase (V-ATPase), has been associated with intellectual disability (ID) and Parkinsonism. ATP6AP2 has been implicated in several signalling pathways; however, little is known regarding its role in the nervous system. To decipher its function in behaviour and cognition, we generated and characterized conditional knockdowns of ATP6AP2 in the nervous system of Drosophila and mouse models. In Drosophila, ATP6AP2 knockdown induced defective phototaxis and vacuolated photoreceptor neurons and pigment cells when depleted in eyes and altered short- and long-term memory when depleted in the mushroom body. In mouse, conditional Atp6ap2 deletion in glutamatergic neurons (Atp6ap2(Camk2aCre/0) mice) caused increased spontaneous locomotor activity and altered fear memory. Both Drosophila ATP6AP2 knockdown and Atp6ap2(Camk2aCre/0) mice presented with presynaptic transmission defects, and with an abnormal number and morphology of synapses. In addition, Atp6ap2(Camk2aCre/0) mice showed autophagy defects that led to axonal and neuronal degeneration in the cortex and hippocampus. Surprisingly, axon myelination was affected in our mutant mice, and axonal transport alterations were observed in Drosophila. In accordance with the identified phenotypes across species, genome-wide transcriptome profiling of Atp6ap2(Camk2aCre/0) mouse hippocampi revealed dysregulation of genes involved in myelination, action potential, membrane-bound vesicles and motor behaviour. In summary, ATP6AP2 disruption in mouse and fly leads to cognitive impairment and neurodegeneration, mimicking aspects of the neuropathology associated with ATP6AP2 mutations in humans. Our results identify ATP6AP2 as an essential gene for the nervous system.
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Trastornos del Conocimiento/etiología , Proteínas de Drosophila/genética , Proteínas de la Membrana/genética , Degeneración Nerviosa/etiología , ATPasas de Translocación de Protón/genética , Receptores de Superficie Celular/genética , Animales , Encéfalo/metabolismo , Encéfalo/fisiopatología , Trastornos del Conocimiento/genética , Trastornos del Conocimiento/fisiopatología , Modelos Animales de Enfermedad , Drosophila , Femenino , Técnicas de Silenciamiento del Gen , Discapacidad Intelectual/genética , Masculino , Ratones , Degeneración Nerviosa/patología , Neuronas/metabolismo , Neuronas/fisiología , Neuronas/ultraestructura , Trastornos Parkinsonianos/genética , Sinapsis/metabolismo , Sinapsis/fisiología , Sinapsis/ultraestructuraRESUMEN
The function of the majority of genes in the mouse and human genomes remains unknown. The mouse embryonic stem cell knockout resource provides a basis for the characterization of relationships between genes and phenotypes. The EUMODIC consortium developed and validated robust methodologies for the broad-based phenotyping of knockouts through a pipeline comprising 20 disease-oriented platforms. We developed new statistical methods for pipeline design and data analysis aimed at detecting reproducible phenotypes with high power. We acquired phenotype data from 449 mutant alleles, representing 320 unique genes, of which half had no previous functional annotation. We captured data from over 27,000 mice, finding that 83% of the mutant lines are phenodeviant, with 65% demonstrating pleiotropy. Surprisingly, we found significant differences in phenotype annotation according to zygosity. New phenotypes were uncovered for many genes with previously unknown function, providing a powerful basis for hypothesis generation and further investigation in diverse systems.