Prenatal exposure to environmental insults can increase the risk of developing neurodevelopmental disorders.Administration of the antiepileptic drug valproic acid(VPA)during pregnancy is tightly associated with a high...Prenatal exposure to environmental insults can increase the risk of developing neurodevelopmental disorders.Administration of the antiepileptic drug valproic acid(VPA)during pregnancy is tightly associated with a high risk of neurological disorders in offspring.However,the lack of an ideal human model hinders our comprehensive understanding of the impact of VPA exposure on fetal brain development,especially in early gestation.Herein,we present the first report indicating the effects of VPA on brain development at early stages using engineered cortical organoids from human induced pluripotent stem cells(hiPSCs).Cortical organoids were generated on micropillar arrays in a controlled manner,recapitulating the critical features of human brain development during early gestation.With VPA exposure,cortical organoids exhibited neurodevelopmental dysfunction characterized by increased neuron progenitors,inhibited neuronal differentiation and altered forebrain regionalization.Transcriptome analysis showed new markedly altered genes(e.g.,KLHL1,LHX9,and MGARP)and a large number of differential expression genes(DEGs),some of which are related to autism.In particular,comparison of transcriptome data via GSEA and correlation analysis revealed the high similarity between VPA-exposed organoids with the postmortem ASD brain and autism patient-derived organoids,implying the high risk of autism with prenatal VPA exposure,even in early gestation.These new findings facilitate a better understanding of the cellular and molecular mechanisms underlying postnatal brain disorders(such as autism)with prenatal VPA exposure.This established cortical organoid-on-a-chip platform is valuable for probing neurodevelopmental disorders under environmental exposure and can be extended to applications in the study of diseases and drug testing.展开更多
Genetic composition plays critical roles in the pathogenesis of autism spectrum disorder(ASD).Especially,inherited and de novo intronic variants are often seen in patients with ASD.However,the biological significance ...Genetic composition plays critical roles in the pathogenesis of autism spectrum disorder(ASD).Especially,inherited and de novo intronic variants are often seen in patients with ASD.However,the biological significance of intronic variants is difficult to address.Here,among a Chinese ASD cohort,we identified a recurrent inherited intronic variant in the CHD7 gene,which is specifically enriched in East Asian populations.CHD7 has been implicated in numerous developmental disorders including CHARGE syndrome and ASD.To investigate whether the ASD-associated CHD7 intronic variant affects neural development,we established human embryonic stem cells carrying this variant using CRISPR/Cas9 methods and found that the level of CHD7 mRNA significantly decreased compared to control.Upon differentiation towards the forebrain neuronal lineage,we found that neural cells carrying the CHD7 intronic variant exhibited developmental delay and maturity defects.Importantly,we found that TBR1,a gene also implicated in ASD,was significantly increased in neurons carrying the CHD7 intronic variant,suggesting the intrinsic relevance among ASD genes.Furthermore,the morphological defects found in neurons carrying CHD7 intronic mutations were rescued by knocking down TBR1,indicating that TBR1 may be responsible for the defects in CHD7-related disorders.Finally,the CHD7 intronic variant generated three abnormal forms of transcripts through alternative splicing,which all exhibited loss-of-function in functional assays.Our study provides crucial evidence supporting the notion that the intronic variant of CHD7 is potentially an autism susceptibility site,shedding new light on identifying the functions of intronic variants in genetic studies of autism.展开更多
基金This research was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Nos.XDB32030200,XDB29050301,XDA16020900)the National Science and Technology Major Project(No.2018ZX09201017-001-001)+2 种基金the National Key R&D Program of China(No.2017YFB0405400)the National Nature Science Foundation of China(Nos.31671038,31971373)the Innovation Program of Science and Research from the DICP,CAS(DICP TMSR201601).
文摘Prenatal exposure to environmental insults can increase the risk of developing neurodevelopmental disorders.Administration of the antiepileptic drug valproic acid(VPA)during pregnancy is tightly associated with a high risk of neurological disorders in offspring.However,the lack of an ideal human model hinders our comprehensive understanding of the impact of VPA exposure on fetal brain development,especially in early gestation.Herein,we present the first report indicating the effects of VPA on brain development at early stages using engineered cortical organoids from human induced pluripotent stem cells(hiPSCs).Cortical organoids were generated on micropillar arrays in a controlled manner,recapitulating the critical features of human brain development during early gestation.With VPA exposure,cortical organoids exhibited neurodevelopmental dysfunction characterized by increased neuron progenitors,inhibited neuronal differentiation and altered forebrain regionalization.Transcriptome analysis showed new markedly altered genes(e.g.,KLHL1,LHX9,and MGARP)and a large number of differential expression genes(DEGs),some of which are related to autism.In particular,comparison of transcriptome data via GSEA and correlation analysis revealed the high similarity between VPA-exposed organoids with the postmortem ASD brain and autism patient-derived organoids,implying the high risk of autism with prenatal VPA exposure,even in early gestation.These new findings facilitate a better understanding of the cellular and molecular mechanisms underlying postnatal brain disorders(such as autism)with prenatal VPA exposure.This established cortical organoid-on-a-chip platform is valuable for probing neurodevelopmental disorders under environmental exposure and can be extended to applications in the study of diseases and drug testing.
基金the National Key R&D Program of China(2018YFA0108000)the National Natural Science Foundation of China(31625013,81941405,31771137,31722024,91732302,and 32000726)+4 种基金a Shanghai Brain-Intelligence Project from the Science and Technology Commission of Shanghai Municipality(16JC1420501)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDBS01060200 and XDA16010310)a Shanghai Municipal Science and Technology Major Project(2018SHZDZX05)the Shanghai Pujiang Program(17PJ1410200)the research was supported by the Open Large Infrastructure Research of the Chinese Academy of Sciences.
文摘Genetic composition plays critical roles in the pathogenesis of autism spectrum disorder(ASD).Especially,inherited and de novo intronic variants are often seen in patients with ASD.However,the biological significance of intronic variants is difficult to address.Here,among a Chinese ASD cohort,we identified a recurrent inherited intronic variant in the CHD7 gene,which is specifically enriched in East Asian populations.CHD7 has been implicated in numerous developmental disorders including CHARGE syndrome and ASD.To investigate whether the ASD-associated CHD7 intronic variant affects neural development,we established human embryonic stem cells carrying this variant using CRISPR/Cas9 methods and found that the level of CHD7 mRNA significantly decreased compared to control.Upon differentiation towards the forebrain neuronal lineage,we found that neural cells carrying the CHD7 intronic variant exhibited developmental delay and maturity defects.Importantly,we found that TBR1,a gene also implicated in ASD,was significantly increased in neurons carrying the CHD7 intronic variant,suggesting the intrinsic relevance among ASD genes.Furthermore,the morphological defects found in neurons carrying CHD7 intronic mutations were rescued by knocking down TBR1,indicating that TBR1 may be responsible for the defects in CHD7-related disorders.Finally,the CHD7 intronic variant generated three abnormal forms of transcripts through alternative splicing,which all exhibited loss-of-function in functional assays.Our study provides crucial evidence supporting the notion that the intronic variant of CHD7 is potentially an autism susceptibility site,shedding new light on identifying the functions of intronic variants in genetic studies of autism.
