Project description:To identify the activity-induced gene expression programs in inhibitory and excitatory neurons, we analyzed RNA extracted from cultured E14 mouse MGE- and CTX-derived neurons (DIV 10) after these cultures were membrane-depolarized for 0, 1 and 6 hrs with 55mM extracellular KCl. To identify the gene programs regulated in these cells by the activity-induced early-response transcription factor Npas4, we repeated the same experiment in the MGE- and CTX-cultures lacking Npas4 (Npas4-KO). Littermate mouse E14 MGE- or CTX-derived neurons (WT or KO for Npas4) were cultured for 9 days, quieted overnight with TTX and AP-5 and then membrane-depolarized for 0, 1 or 6 hours by raising the extracellular KCl-concentration to 55mM. RNA was then extracted and analyzed using Affymetrix GeneChip Mouse Expression Set 430 2.0 microarray platform.
Project description:To identify the activity-induced gene expression programs in inhibitory and excitatory neurons, we analyzed RNA extracted from cultured E14 mouse MGE- and CTX-derived neurons (DIV 10) after these cultures were membrane-depolarized for 0, 1 and 6 hrs with 55mM extracellular KCl. To identify the gene programs regulated in these cells by the activity-induced early-response transcription factor Npas4, we repeated the same experiment in the MGE- and CTX-cultures lacking Npas4 (Npas4-KO).
Project description:we used DNA microarray analysis to identify genes that are induced by neuronal activity in excitatory neurons at the time when inhibitory synapses are forming and maturing on them. Experiment Overall Design: We cultured cortical neurons for 7 DIV until the process of inhibitory synapse development was underway, and then depolarized the neurons with 50 mM of KCl to activate L-type voltage-sensitive calcium channels (L-VSCCs) for 0, 1 or 6 hours, the cells were lysed, mRNA isolated and hybridized to Affymetrix arrays. Data were collected from 3 independent experiments.
Project description:This SuperSeries is composed of the following subset Series:; GSE11256: KCl depolarization-regulated genes in mouse cortical neurons; GSE11258: Npas4-regulated genes in mouse hippocampal neurons Experiment Overall Design: Refer to individual Series
Project description:The development of cortical circuits, made up of excitatory neurons and inhibitory interneurons, is a fine-tuned and vital process during brain development. Aberrations affecting the establishment of these circuits are implicated in several neuropsychiatric and neurological disorders. While excitatory neurons originate in cortical proliferative zones, inhibitory interneurons migrate from the basal telencephalon into the cortex. This migration is regulated by intrinsic genetic programs and extrinsic cues. Here, we aimed to identify the role of the DNA methyltransferase 1 (DNMT1) in controlling the expression of key genes implicated in the development and migration of post-mitotic somatostatin-positive interneurons as well as its impact on the rest of the cortical population.
Project description:The establishment of neuronal circuits, made up of excitatory neurons and inhibitory interneurons, is a fine-tuned process during corticogenesis and is pivotal for a functional brain. Developmental aberrations affecting these circuits are implicated in several neuropsychiatric disorders. While excitatory neurons originate in cortical proliferative zones, inhibitory interneurons migrate from the basal telencephalon into the cortex. This migration is regulated by intrinsic genetic programs and extrinsic cues. Here, we aimed to identify the role of the DNA methyltransferase 1 (DNMT1) in controlling the expression of key genes implicated in mouse cortical interneuron development and the migration of somatostatin-expressing interneurons within the developing cortex.
Project description:The establishment of neuronal circuits, made up of excitatory neurons and inhibitory interneurons, is a fine-tuned process during corticogenesis and is pivotal for a functional brain. Developmental aberrations affecting these circuits are implicated in several neuropsychiatric disorders. While excitatory neurons originate in cortical proliferative zones, inhibitory interneurons migrate from the basal telencephalon into the cortex. This migration is regulated by intrinsic genetic programs and extrinsic cues. Here, we aimed to identify the role of the DNA methyltransferase 1 (DNMT1) in controlling the expression of key genes implicated in mouse cortical interneuron development and the migration of somatostatin-expressing interneurons within the developing cortex.
Project description:CDKL5 deficiency disorder (CDD) is a rare developmental and epileptic encephalopathy resulting from variants in cyclin-dependent kinase-like 5 (CDKL5) that lead to impaired kinase activity or loss of function. CDD is one of the most common genetic etiologies identified in epilepsy cohorts. To study how CDKL5 variants impact human neuronal activity, gene expression and morphology, CDD patient-derived induced pluripotent stem cells and their isogenic controls were differentiated into excitatory neurons using either an NGN2 induction protocol or a guided cortical organoid differentiation. Patient-derived neurons from both differentiation paradigms had decreased phosphorylated EB2, a known molecular target of CDKL5. Induced neurons showed no detectable differences between cases and isogenic controls in network activity using a multielectrode array, or in MAP2+ neurite length, and only two genes were differentially expressed. However, patient-derived neurons from the organoid differentiation showed increased synchrony and weighted mean firing rate on the multielectrode array within the first month of network maturation. CDD patient-derived cortical neurons had lower expression of CDKL5 and HS3ST1, which may change the extracellular matrix around the synapse and contribute to hyperexcitability. Similar to the induced neurons, there were no differences in neurite length across or within patient-control cell lines. Induced neurons have poor cortical specification while the organoid derived neurons expressed cortical markers, suggesting that the changes in neuronal excitability and gene expression are specific to cortical excitatory neurons. Examining molecular mechanisms of early hyperexcitability in cortical neurons is a promising avenue for identification of CDD therapeutics.
