Project description:We aim to profile the transcriptomic changes in neurons when responding to cooling, in order to understand the neuroprotective effects of hypothermia. polyA selected RNA-seq were performed from human iPSC-derived cortical neurons under control (37 ºC), cooled (72 h at 32 ºC, day 15-18) and rewarmed (72 h at 32 ºC, day 15-18, followed by 72 h at 37 ºC, day 18-21) conditions.
Project description:We have assessed the importance of SQSTM1 in human induced pluripotent stem cell (iPSC)-derived cortical neurons with and without SQSTM1. By combining high-content imaging, RNA-Seq, and functional mitochondrial readouts, we showed that SQSTM1 depletion causes aberrations in mitochondrial gene expression and functionality in iPSC-derived neurons.
Project description:Induced pluripotent stem cell (iPSC)-derived cortical neurons present a powerful new model of neurological disease. Previous work has established that differentiation protocols produce cortical neurons but little has been done to characterise these at cellular resolution. In particular, it is unclear to what extent in vitro two-dimensional, relatively disordered culture conditions recapitulate the development of in vivo cortical layer identity. Single cell multiplex RT-qPCR was used to interrogate the expression of genes previously implicated in cortical layer or phenotypic identity in individual cells. Unexpectedly, 22.7% of neurons analysed frequently co-expressed canonical fetal deep and upper cortical layer markers, and this co-expression was also present at the level of translated protein. By comparing our results to available single cell RNA-seq data from human fetal and adult brain, we observed that this co-expression of layer markers was also seen in primary tissue. These results suggest that establishing neuronal layer identity in iPSC-derived or primary cortical neurons using canonical marker genes transcripts is unlikely to be informative. Single cell RNA-seq of 16 iPSC-derived cortical neurons. This dataset was used for normalization purposes for GSE67835.
Project description:Proteostasis involves a dynamic network of biological pathways that regulate protein synthesis, maintenance, and degradation. As postmitotic cells, neurons are particularly sensitive to environmental changes, and dysfunction in cellular proteostasis can lead to an accumulation of aggregated and misfolded proteins. However, how proteins turnover on a global scale in human neurons is not well understood. In this study, we systematically improved a dynamic SILAC proteomic approach to enable a deep and accurate measurement of protein turnover in human induced pluripotent stem cell (iPSC)-derived cholinergic spinal motor and glutamatergic cortical neurons. Furthermore, we applied this deep proteome turnover method to evaluate how inhibiting the ubiquitin-proteasome and lysosome-autophagy pathway impacts proteostasis in iPSC-derived neurons. Using these datasets, we developed a freely available resource called Neuron Profile, an interactive website for visualizing and querying protein turnover in subcellular locations in human neurons.
Project description:Alterations in cortical neurogenesis are implicated in neurodevelopmental disorders including autism spectrum disorders (ASDs). Many ASD risk genes have been identified as critical for brain development, but the contribution of genetic backgrounds, although inferred in complex genetic disorders such as ASD, remains unclear. Here, using isogenic induced pluripotent stem cell (iPSC)-derived neural progenitor cells (NPCs) and cortical organoid models, we report that a heterozygous PTEN p.I135L mutation found in an ASD patient with macrocephaly dysregulates cortical neurogenesis in an ASD genetic background-dependent fashion. We found that this PTEN p.I135L mutation led to overproduction of NPC subtypes as well as neuronal subtypes including both deep and upper layer neurons in its ASD background, but not when introduced into a control genetic background. ASD and control background differences in neurogenesis, neural development and synapse signaling were also observed. These findings provide experimental evidence that both a PTEN p.I135L mutation and ASD genetic background contribute to cellular features consistent with ASD associated with macrocephaly.
Project description:Huntington's disease (HD) is a neurodegenerative disease caused by an expanded CAG repeat in the Huntingtin (HTT) gene. Induced pluripotent stem cell (iPSC) models of HD provide an opportunity to study the mechanisms underlying disease pathology in patient tissues relevant to disease. Murine studies have demonstrated that HTT is intricately involved in corticogenesis, and mutant (mt) HTT cannot compensate for the loss of non-CAG-expanded HTT. However, the critical effect of mtHTT in human corticogenesis has not yet been specifically explored and due to inherent differences in cortical development and timing between humans and mice. We therefore differentiated HD and non-diseased iPSCs into functional cortical neurons. While HD patient iPSCs can be successfully differentiated towards a cortical fate in culture, the resulting neurons display transcriptomic, morphological and functional phenotypes indicative of altered neurodevelopment. This is the first demonstration of altered corticogenesis from HD human patient cells, further supporting the potential neurodevelopmental aspect of HD.
Project description:Single-cell RNA-seq: We used single-cell RNAseq to investigate the maturation of astrocytes within human cortical spheroids Bulk RNA-seq: Bulk sequencing from astrocytes and neurons purified (via immunopanning) from iPSC-derived coritical spheroids at varying in vitro differentiation states