Project description:Tuberous Sclerosis Complex (TSC), an autosomal dominant condition, is engendered by heterozygous mutations in either TSC1 or TSC2 genes, manifesting in systemic growth of benign tumors. In addition to brain lesions, neurologic sequelae represent the greatest morbidity in TSC patients. Investigations utilizing TSC1/2-knockout animal or human stem cell models suggest that TSC deficiency-causing hyper-activation of mTOR signaling might precipitate anomalous neurodevelopmental processes. However, how the pathogenic variants of TSC1/2 genes identified in TSC patients affect the trajectory of human brain development and how they contribute to the neurological manifestations in TSC remain largely unexplored. Here, we employed 3-dimensional cortical organoids derived from induced pluripotent stem cells (iPSCs) from TSC patients harboring TSC2 mutations, alongside organoids from age- and sex-matched healthy individuals as controls. Through comprehensively longitudinal molecular and cellular analysis of TSC organoids, including transcriptomics and single cell transcriptomics, we found that TSC2 pathogenic variants led to dysregulated neurogenesis, synaptogenesis, and gliogenesis, particularly for reactive astrogliosis. The altered developmental trajectory of TSC organoids significantly resembles the molecular signatures of neuropsychiatric disorders, including autism spectrum disorders, epilepsy, and intellectual disability. Through cell-cell communication analysis at the single cell level, we identified that TSC2 pathogenic variants disrupted the cell-cell communications, in particular, neuron-astrocyte interactions within the NLGN-NRXN signaling network. Furthermore, cellular and electrophysiological assessments of TSC cortical organoids, along with proteomics and phosphoproteomics analyses of synaptosomes, revealed that pathogenic TSC2 variants precipitate perturbations in mitochondrial translational integrity, neurofilament formation, synaptic transmission, and neuronal network activity. Intriguingly, the increased neu

Project description:Background: Chronic spinal cord injury (SCI) remains one of the most debilitating neurological disorders and the majority of SCI patients are in the chronic phase. Previous studies of SCI that were limited by resources and technology have usually focused on few genes and pathways at a time. Thus, a comprehensive view of the complex molecular changes underlying SCI pathophysiology is needed. In particular, the biological roles of long non-coding RNAs (lncRNAs), a class of regulatory RNAs, have never been characterized systemically in SCI. Results: This study is the first to investigate alterations in the expression of both coding and long non-coding genes in the sub-chronic and chronic stages of SCI using RNA-Sequencing. Our data revealed differentially expressed genes, canonical pathways, and networks unique to particular time points or common to multiple time points in the progression of SCI. For example, a network of multiple critical genes responsible for astrogliosis and fibrosis was identified among differentially expressed genes common to three time points (1month, 3months, and 6 months after SCI). Moreover, the potential functions of rat lncRNAs in SCI were extensively analyzed. First, a comprehensive annotation database was compiled for rat lncRNAs that revealed several interesting characteristics of lncRNAs in the rat genome. Then, by correlating the temporal expression patterns of lncRNAs with those of protein-coding genes, we identified lncRNAs that are associated with functional categories such as signaling pathways, immune response, epigenetic modification, nervous system, and extracellular matrix. The expression patterns of some lncRNAs are highly correlated with those of their most proximal protein-coding genes, so it is possible that these lncRNAs regulate the expression of their protein-coding neighbors. Finally, we searched for transcription factor motifs enriched in the upstream regulatory regions of differentially expressed lncRNAs, and identified differentially expressed lncRNAs that are homologous to human genomic regions harboring molecular variants associated with human neurological diseases. Conclusions: Overall, our study provides an unprecedented resource for the study of sub-chronic and chronic SCI that will help the research community identify new molecular targets for future functional investigation.

Dataset Information

Coding and small non-coding transcriptional landscape of tuberous sclerosis complex cortical tubers: implications for pathophysiology and treatment

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets