Project description:Monogenic neurodevelopmental disorders provide key insights into the pathogenesis of disease and help us understand how specific genes control the development of the human brain. Timothy syndrome is caused by a missense mutation in the L-type calcium channel Cav1.2 that is associated with developmental delay and autism. We generated cortical neuronal precursor cells and neurons from induced pluripotent stem cells derived from individuals with Timothy syndrome. Cells from these individuals have defects in calcium (Ca2+) signaling and activity-dependent gene expression and show abnormalities in differentiation. Neurons from individuals with Timothy syndrome show increased expression of markers of the upper cortical layer and decreased expression of callosal projection markers. In addition, the mutation that causes Timothy syndrome leads to an increase in the production of neurons that synthesize norepinephrine and dopamine. This phenotype can be reversed by treatment with roscovitine, a cyclin-dependent kinase and atypical L-type–channel blocker. These findings provide strong evidence that Cav1.2 regulates the differentiation of cortical neurons in humans and offer new insights into the causes of autism in individuals with Timothy syndrome. Total RNA was isolated from control and TS cells: fibroblasts, iPSCs, neurospheres (at day 7 in suspension), neurons at rest (day 45 of differentiation) and neurons kept in 67mM KCl for 9h. For sample titles, D1,D2 and D3 represent independent differentiation experiments. The number after - represents the iPSC cell line number. GSE25542_non-normalized.txt.gz contains data for 5 outliers.
Project description:Mutation of marA, rob, and soxS causes a clinical strain of E.coli to be attenuated at d3 post-infection in a mouse model of pyelonephritis, here we extract RNA at d2 post infection to analyze transcriptional differences between the two strains.
2010-10-01 | GSE23417 | GEO
Project description:Gene Mutation Causes a Syndrome of Combined Immunodeficiency
Project description:Hypotonia, ataxia, developmental delay and tooth enamel defect syndrome (HADDTS) is a recently identified syndrome linked to a heterozygous mutation in the C-Terminal Binding Protein 1 (CTBP1) transcriptional corepressor. The mutation is located within the major binding cleft (PXDLS), crucial for CtBP1’s interaction with proteins that regulate gene expression. We generated isogenic induced pluripotent cell lines (iPSCs) with the CTBP1 mutation in heterozygous and homozygous using CRISPR/Cas9 editing method. The transcriptional profile of iPSC-derived early neurons from isogenic wild-type and CTBP1 heterozygous and homozygous mutants was determined by RNA sequencing. The RNA-Seq data revealed downregulation of several key transcriptional factors, with homozygous mutations causing more pronounced downregulation than heterozygous mutations. Isogenic mutant neural stem cells (NSCs) exhibited less adhesion, migration, and calcium dysregulation, and mutant neurons showed premature neurite outgrowth. Our transcriptome and biological results provide novel insight into the mechanism of CTBP1 p.R342W mutation's role in the defective neurodevelopmental process.
Project description:Monogenic neurodevelopmental disorders provide key insights into the pathogenesis of disease and help us understand how specific genes control the development of the human brain. Timothy syndrome is caused by a missense mutation in the L-type calcium channel Cav1.2 that is associated with developmental delay and autism. We generated cortical neuronal precursor cells and neurons from induced pluripotent stem cells derived from individuals with Timothy syndrome. Cells from these individuals have defects in calcium (Ca2+) signaling and activity-dependent gene expression and show abnormalities in differentiation. Neurons from individuals with Timothy syndrome show increased expression of markers of the upper cortical layer and decreased expression of callosal projection markers. In addition, the mutation that causes Timothy syndrome leads to an increase in the production of neurons that synthesize norepinephrine and dopamine. This phenotype can be reversed by treatment with roscovitine, a cyclin-dependent kinase and atypical L-type–channel blocker. These findings provide strong evidence that Cav1.2 regulates the differentiation of cortical neurons in humans and offer new insights into the causes of autism in individuals with Timothy syndrome.
Project description:Grainyhead-like transcription factor 3 (GRHL3) directs surface ectoderm differentiation under the control of the canonical Wnt/β-catenin pathway. However, the molecular mechanisms that control nuclear GRHL3 expression through β-catenin are not fully understood. Here, we show that the essential for mitotic growth 1 (EMG1) protein constitutes a protein complex with GRHL3, and that EMG1 is required for correct nuclear localization of GRHL3, and for activation of the canonical Wnt signaling pathway. Conditional knockout mutation of Emg1 in the GRHL3-positive surface ectoderm causes neural tube defects at the level of the spinal cord, i.e. spina bifida. Additionally, the severity of compound mutant phenotypes of the Emg1 and Grhl3 genes indicates that they interact genetically in neurulation and palate development. These lines of evidence demonstrate that EMG1 cooperates with GRHL3 in β-catenin–mediated surface ectoderm differentiation. Since the EMG1 mutation causes Bowen-Conradi syndrome and the GRHL3 mutation causes Van der Woude syndrome 2, both of which are associated with neural tube dysplasia and cleft palate, our study will help to better understand the pathogenic mechanisms of these two human genetic diseases.