| [article] 
					| Titre : | Distinct, dosage-sensitive requirements for the autism-associated factor CHD8 during cortical development |  
					| Type de document : | texte imprimé |  
					| Auteurs : | S. HURLEY, Auteur ; C. MOHAN, Auteur ; P. SUETTERLIN, Auteur ; R. ELLINGFORD, Auteur ; K. L. H. RIEGMAN, Auteur ; J. ELLEGOOD, Auteur ; A. CARUSO, Auteur ; C. MICHETTI, Auteur ; O. BROCK, Auteur ; R. EVANS, Auteur ; F. RUDARI, Auteur ; A. DELOGU, Auteur ; M. L. SCATTONI, Auteur ; J. P. LERCH, Auteur ; C. FERNANDES, Auteur ; M. A. BASSON, Auteur |  
					| Article en page(s) : | 16 p. |  
					| Langues : | Anglais (eng) |  
					| Mots-clés : | Animals  Animals, Newborn  Autistic Disorder/genetics  Behavior, Animal  Brain/diagnostic imaging/embryology/growth & development  Cell Proliferation  DNA-Binding Proteins/deficiency/genetics  Disease Models, Animal  Female  Gene Expression Regulation, Developmental  Mice, Transgenic  Phenotype  Pregnancy  Stem Cells  Tumor Suppressor Protein p53/genetics  Apoptosis  Autism  Chd8  Chromatin  Conditional knockout  Cortex  Gene expression  Hypomorph  Intermediate progenitor  Mouse  Neural progenitor  Proliferation  Tbr2  p53  Pathways plc. This work is unrelated to COMPASS Pathways plc. No other competing  interests to declare. |  
					| Index. décimale : | PER Périodiques |  
					| Résumé : | BACKGROUND: CHD8 haploinsufficiency causes autism and macrocephaly with high penetrance in the human population. Chd8 heterozygous mice exhibit relatively subtle brain overgrowth and little gene expression changes in the embryonic neocortex. The purpose of this study was to generate new, sub-haploinsufficient Chd8 mouse models to allow us to identify and study the functions of CHD8 during embryonic cortical development. METHODS: To examine the possibility that certain phenotypes may only appear at sub-heterozygous Chd8 levels in the mouse, we created an allelic series of Chd8-deficient mice to reduce CHD8 protein levels to approximately 35% (mild hypomorph), 10% (severe hypomorph) and 0% (neural-specific conditional knockout) of wildtype levels. We used RNA sequencing to compare transcriptional dysregulation, structural MRI and brain weight to investigate effects on brain size, and cell proliferation, differentiation and apoptosis markers in immunostaining assays to quantify changes in neural progenitor fate. RESULTS: Mild Chd8 hypomorphs displayed significant postnatal lethality, with surviving animals exhibiting more pronounced brain hyperplasia than heterozygotes. Over 2000 genes were dysregulated in mild hypomorphs, including autism-associated neurodevelopmental and cell cycle genes. We identify increased proliferation of non-ventricular zone TBR2+ intermediate progenitors as one potential cause of brain hyperplasia in these mutants. Severe Chd8 hypomorphs displayed even greater transcriptional dysregulation, including evidence for p53 pathway upregulation. In contrast to mild hypomorphs, these mice displayed reduced brain size and increased apoptosis in the embryonic neocortex. Homozygous, conditional deletion of Chd8 in early neuronal progenitors resulted in pronounced brain hypoplasia, partly caused by p53 target gene derepression and apoptosis in the embryonic neocortex. Limitations Our findings identify an important role for the autism-associated factor CHD8 in controlling the proliferation of intermediate progenitors in the mouse neocortex. We propose that CHD8 has a similar function in human brain development, but studies on human cells are required to confirm this. Because many of our mouse mutants with reduced CHD8 function die shortly after birth, it is not possible to fully determine to what extent reduced CHD8 function results in autism-associated behaviours in mice. CONCLUSIONS: Together, these findings identify important, dosage-sensitive functions for CHD8 in p53 pathway repression, neurodevelopmental gene expression and neural progenitor fate in the embryonic neocortex. We conclude that brain development is acutely sensitive to reduced CHD8 expression and that the varying sensitivities of different progenitor populations and cellular processes to CHD8 dosage result in non-linear effects on gene transcription and brain growth. Shaun Hurley, Conor Mohan and Philipp Suetterlin have contributed equally to this work. |  
					| En ligne : | http://dx.doi.org/10.1186/s13229-020-00409-3 |  
					| Permalink : | https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=459 |  in Molecular Autism > 12  (2021) . - 16 p.
 [article] Distinct, dosage-sensitive requirements for the autism-associated factor CHD8 during cortical development [texte imprimé] / S. HURLEY , Auteur ; C. MOHAN , Auteur ; P. SUETTERLIN , Auteur ; R. ELLINGFORD , Auteur ; K. L. H. RIEGMAN , Auteur ; J. ELLEGOOD , Auteur ; A. CARUSO , Auteur ; C. MICHETTI , Auteur ; O. BROCK , Auteur ; R. EVANS , Auteur ; F. RUDARI , Auteur ; A. DELOGU , Auteur ; M. L. SCATTONI , Auteur ; J. P. LERCH , Auteur ; C. FERNANDES , Auteur ; M. A. BASSON , Auteur . - 16 p.Langues  : Anglais (eng )in Molecular Autism  > 12  (2021)  . - 16 p. 
					| Mots-clés : | Animals  Animals, Newborn  Autistic Disorder/genetics  Behavior, Animal  Brain/diagnostic imaging/embryology/growth & development  Cell Proliferation  DNA-Binding Proteins/deficiency/genetics  Disease Models, Animal  Female  Gene Expression Regulation, Developmental  Mice, Transgenic  Phenotype  Pregnancy  Stem Cells  Tumor Suppressor Protein p53/genetics  Apoptosis  Autism  Chd8  Chromatin  Conditional knockout  Cortex  Gene expression  Hypomorph  Intermediate progenitor  Mouse  Neural progenitor  Proliferation  Tbr2  p53  Pathways plc. This work is unrelated to COMPASS Pathways plc. No other competing  interests to declare. |  
					| Index. décimale : | PER Périodiques |  
					| Résumé : | BACKGROUND: CHD8 haploinsufficiency causes autism and macrocephaly with high penetrance in the human population. Chd8 heterozygous mice exhibit relatively subtle brain overgrowth and little gene expression changes in the embryonic neocortex. The purpose of this study was to generate new, sub-haploinsufficient Chd8 mouse models to allow us to identify and study the functions of CHD8 during embryonic cortical development. METHODS: To examine the possibility that certain phenotypes may only appear at sub-heterozygous Chd8 levels in the mouse, we created an allelic series of Chd8-deficient mice to reduce CHD8 protein levels to approximately 35% (mild hypomorph), 10% (severe hypomorph) and 0% (neural-specific conditional knockout) of wildtype levels. We used RNA sequencing to compare transcriptional dysregulation, structural MRI and brain weight to investigate effects on brain size, and cell proliferation, differentiation and apoptosis markers in immunostaining assays to quantify changes in neural progenitor fate. RESULTS: Mild Chd8 hypomorphs displayed significant postnatal lethality, with surviving animals exhibiting more pronounced brain hyperplasia than heterozygotes. Over 2000 genes were dysregulated in mild hypomorphs, including autism-associated neurodevelopmental and cell cycle genes. We identify increased proliferation of non-ventricular zone TBR2+ intermediate progenitors as one potential cause of brain hyperplasia in these mutants. Severe Chd8 hypomorphs displayed even greater transcriptional dysregulation, including evidence for p53 pathway upregulation. In contrast to mild hypomorphs, these mice displayed reduced brain size and increased apoptosis in the embryonic neocortex. Homozygous, conditional deletion of Chd8 in early neuronal progenitors resulted in pronounced brain hypoplasia, partly caused by p53 target gene derepression and apoptosis in the embryonic neocortex. Limitations Our findings identify an important role for the autism-associated factor CHD8 in controlling the proliferation of intermediate progenitors in the mouse neocortex. We propose that CHD8 has a similar function in human brain development, but studies on human cells are required to confirm this. Because many of our mouse mutants with reduced CHD8 function die shortly after birth, it is not possible to fully determine to what extent reduced CHD8 function results in autism-associated behaviours in mice. CONCLUSIONS: Together, these findings identify important, dosage-sensitive functions for CHD8 in p53 pathway repression, neurodevelopmental gene expression and neural progenitor fate in the embryonic neocortex. We conclude that brain development is acutely sensitive to reduced CHD8 expression and that the varying sensitivities of different progenitor populations and cellular processes to CHD8 dosage result in non-linear effects on gene transcription and brain growth. Shaun Hurley, Conor Mohan and Philipp Suetterlin have contributed equally to this work. |  
					| En ligne : | http://dx.doi.org/10.1186/s13229-020-00409-3 |  
					| Permalink : | https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=459 | 
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