Project description:Williams syndrome (WS) is a neurodevelopmental disorder caused by a genomic deletion of ~28 genes that results in a cognitive and behavioral profile marked by overall intellectual impairment with relative strength in expressive language and hypersocial behavior. Advancements in protocols for neuron differentiation from induced pluripotent stem cells allowed us to elucidate the molecular circuitry underpinning the ontogeny of Williams syndrome. In patient-derived stem cells and neurons, we determined the expression profile of the Williams-Beuren Syndrome Critical Region deleted genes and the genome-wide transcriptional consequences of the hemizygous genomic microdeletion at 7q11.23. Derived neurons displayed disease-relevant hallmarks and indicated novel aberrant pathways in WS neurons including over-activated Wnt signaling accompanying an incomplete neurogenic commitment. We show that haploinsufficiency of the ATP-dependent chromatin remodeler, BAZ1B, which is deleted in WS, significantly contributes to this differentiation defect. Chromatin-immunoprecipitation (ChIP-seq) revealed BAZ1B target gene functions are enriched for neurogenesis, neuron differentiation, and disease-relevant phenotypes. BAZ1B haploinsufficiency caused widespread gene expression changes in neural progenitor cells, and together with BAZ1B ChIP-seq target genes, explained 42% of the transcriptional dysregulation in WS neurons. BAZ1B contributes to regulating the balance between neural precursor self-renewal and differentiation and the differentiation defect caused by BAZ1B haploinsufficiency can be rescued by mitigating over-active Wnt signaling in neural stem cells. Altogether, these results reveal a pivotal role for BAZ1B in neurodevelopment and implicate its haploinsufficiency as a likely contributor to the neurological phenotypes in WS.
Project description:While psychiatric disorders (e.g., schizophrenia) and autism spectrum disorders (ASD) are typically associated with a deficit in social behavior, the opposite trait of hypersociability is exhibited by individuals with specific neurodevelopmental disorders, e.g., Angelman Syndrome (AS) and Williams-Beuren Syndrome (WBS). We have recently reported that the deletion of the miR379-410 cluster in mice led to hypersocial behavior. To study the roles of this miRNA cluster in the context of WBS, we sent for smallRNA sequencing RNA isolated from isogenic human iPSC-derived neurons harboring a deletion present in Williams-Beuren-Syndrome patients (7q11.23). Specifically, we found that members of the miR379-410 cluster were strikingly overrepresented among downregulated miRNAs in iNeurons harboring a deletion of the WBS critical region. Thus, we obtained the first evidence for the pathophysiological significance of the miR379-410 miRNA cluster in the context of WBS. We conclude that targeting this novel pathway could have therapeutic potential for WBS and other neurodevelopmental conditions characterized by social impairments.
Project description:Epithelium-only cultured stem cells isolated from human pluripotent stem cell derived intestinal organoids grown in matrigel and alginate
Project description:There are a total of four samples each for this analysis. Each sample consists of the cells grown on three 10 cm culture plates. Each plate should have 2x106 cells for a total of 6x106 cells per sample when all three plates are combined. The first sample is undifferentiated human embryonic stem cells, the second sample is human glutamatergic neurons derived from those human embryonic stem cells, the third sample is undifferentiated human induced pluripotent stem cells and the fourth sample is human glutamatergic neurons derived from those human induced pluripotent stem cells.
Project description:Mus musculus Wbscr25, Williams Beuren syndrome chromosome region 25 (human) [Source:MGI Symbol;Acc:MGI:1918554], is differentially expressed in 19 experiment(s);
Project description:Mus musculus Wbscr25, Williams Beuren syndrome chromosome region 25 (human) [Source:MGI Symbol;Acc:MGI:1918554], is expressed in 10 baseline experiment(s);