Dataset Information

TDP43 proteinopathy exhibits disease, tissue, and context-specific cryptic splicing signatures

ABSTRACT: Mislocalization of the nuclear protein TDP43 is a hallmark of ALS and FTD and leads to de-repression and inclusion of cryptic exons, which represent promising biomarkers of TDP43 pathology. However, most cryptic exons to date have been identified from in vitro models, limiting our understanding of any tissue and/or cell-specific splices. We meta-analyzed published bulk RNA-Seq datasets representing 1,778 RNAseq profiles of ALS and FTD post mortem tissue, and in vitro models with experimentally depleted TDP43. We identified novel cryptic splices and mapped out their tissue-specificity, demonstrating subsets with distinct cortical and spinal cord enrichment. Novel events were validated by RNA-Seq and RT-qPCR in a new spinal cord cohort, and analysis of single-nucleus datasets localized cortical splices to layer-specific neuronal populations. This catalog of cryptic splices is the first step towards the development of biomarkers for cell type-specific TDP43 pathology.

ORGANISM(S): Homo sapiens

PROVIDER: GSE255683 | GEO | 2024/03/28

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:We established iPSCs from healthy donors, SOD1-ALS and TDP43-ALS patients. Using our differentiation protocol originally developed by Reinhardt et al.,2013, we diferentiated these iPSCs toward spinal motor neurons (MNs) and reproduce ALS pathology in a dish. To extend our understanding of finding different molecular mechanisms and pathways related to SOD1- and TDP43 mutations in ALS disease, we have performed a comprehensive gene expression profiling study using RNA-Seq of the iPSC-derived MN models from control individuals and carefully compared with those from SOD1-ALS and TDP43-ALS patients. To generate novel hypotheses of putative underlying molecular mechanisms in ALS, we used human induced pluripotent stem cell (hiPSCs)-derived motor neurons (MNs) from SOD1- and TARDBP (TDP-43 protein)-mutant-ALS patients and healthy controls to perform high-throughput RNA-sequencing (RNA-Seq). An integrated bioinformatics approach was employed to identify differentially expressed genes (DEGs) and key pathways underlying these familial forms of the disease (fALS). In TDP43-ALS, we found dysregulation of transcripts encoding components of the transcriptional machinery and transcripts involved in splicing regulation were particularly affected. In contrast, less is known about the role of SOD1 in RNA metabolism in motor neurons. Here we found that many transcripts relevant for mitochondrial function were specifically altered in SOD1-ALS, indicating transcriptional signatures and expression patterns can vary significantly depending on the causal gene that is mutated. Surprisingly, however, we identified a clear downregulation of genes involved in protein translation in SOD1-ALS suggesting that ALS-causing SOD1 mutations shift cellular RNA abundance profiles to cause neural dysfunction. Altogether, we provided here an extensive profiling of mRNA expression in two ALS models at the cellular level, corroborating the major role of RNA metabolism and protein translation as a common pathomechanism in ALS

Project description:Burgeoning evidence highlights seminal roles for microglia in the pathogenesis of neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). The receptor for advanced glycation end products (RAGE) binds ligands relevant to ALS that accumulate in the diseased spinal cord and RAGE has been previously implicated in the progression of ALS pathology. We generated a novel mouse model to temporally delete Ager from microglia in the murine SOD1G93A model of ALS. Microglia Ager deficient SOD1G93A mice and controls were examined for changes in survival, motor function, gliosis, motor neuron numbers, and transcriptomic analyses of lumbar spinal cord. Furthermore, we examined bulk-RNA-sequencing transcriptomic analyses of human ALS cervical spinal cord. Transcriptomic analysis of human cervical spinal cord reveals a range of AGER expression in ALS patients, which was negatively correlated with age at disease onset and death or tracheostomy. The degree of AGER expression related to differential expression of pathways involved in extracellular matrix, lipid metabolism, and intercellular communication. Microglia display increased RAGE immunoreactivity in the spinal cords of high AGER expressing patients and in the SOD1G93A murine model of ALS vs. respective controls. We demonstrate that microglia Ager deletion at the age of symptomatic onset, day 90, in SOD1G93A mice extends survival in male but not female mice. Critically, many of the pathways identified in human ALS patients that accompanied increased AGER expression were significantly ameliorated by microglia Ager deletion in male SOD1G93A mice. Our results indicate that microglia RAGE disrupts communications with cell types including astrocytes and neurons, intercellular communication pathways that divert microglia from a homeostatic to an inflammatory and tissue-injurious program. In totality, microglia RAGE contributes to the progression of SOD1G93A murine pathology in male mice and may be relevant in human disease.

Dataset Information

TDP43 proteinopathy exhibits disease, tissue, and context-specific cryptic splicing signatures

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets