Project description:Poly(GR) impairs protein translation and stress granule dynamics in C9orf72-associated frontotemporal dementia and amyotrophic lateral sclerosis
Project description:Purpose: The purpose of this experiment is to identify a C9-ALS/FTD specific genomic profile in fibroblast lines that is distinct from sporadic ALS without C9orf72 expansion and non-neurologic control cells. The study will then evaluate the effect on this identified profile of ASO treatment targeting the sense strand RNA transcript of the C9orf72 gene. Methods: Expression profiling was performed on RNAs from fibroblasts of four C9orf72 patients, four control individuals and four sporadic ALS patients using Multiplex Analysis of PolyA-linked Sequences method. Results: Hierarchical clustering of expression values for all genes showed that the four C9orf72 patient lines had an expression profile distinct from control and sporadic ALS lines. Statistical comparison of expression values between the four C9orf72 lines and the four control lines revealed that 122 genes were upregulated (defined by a False Discovery Rate FDR<0.05) and 34 genes were downregulated (defined by a False Discovery Rate FDR <0.05) in C9orf72 patient fibroblasts. Conclusions: A genome wide RNA signature can be defined in fibroblasts with C9orf72 expansion. ASO-mediated reduction of C9orf72 RNA levels in fibroblasts with the hexanucleotide expansion efficiently reduced accumulation of GGGGCC RNA foci. This did not, however, generate a reversal of the C9orf72 RNA profile. Use of Multiplex Analysis of PolyA-linked Sequences to identify expression changes in fibroblasts from amyotrophic lateral sclerosis and frontotemporal dementia patients harboring an hexanucleotide expansion in the C9orf72 gene.
Project description:Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share key features, including accumulation of the RNA binding protein TDP-43. TDP-43 regulatesRNA homeostasis, but it remains unclear whether RNA stability is affected in these disorders. We used Bru-seq and BruChase-seq to assessgenome-wide RNA stabilityinALS patient-derived cells,demonstratingprofound destabilization of ribosomal and mitochondrial transcripts. This pattern wasrecapitulatedbyTDP-43 overexpression, suggesting a primary role for TDP-43 in RNA destabilization, and in post-mortem samples from ALS and FTD patients. Proteomics and functional studies illustrated corresponding reductionsin mitochondrial components and compensatory increasesin protein synthesis. Collectively, these observations suggest that TDP-43 deposition leads to targeted RNA instability in ALS and FTD, ultimately causing cell death by disrupting energy production and protein synthesis pathways.
Project description:Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share key features, including accumulation of the RNA binding protein TDP-43. TDP-43 regulates RNA homeostasis, but it remains unclear whether RNA stability is affected in these disorders. We use Bru-seq and BruChase-seq to assess genome-wide RNA stability in ALS patient-derived cells, demonstrating profound destabilization of ribosomal and mitochondrial transcripts. This pattern is recapitulated by TDP-43 overexpression, suggesting a primary role for TDP-43 in RNA destabilization, and in post-mortem samples from ALS and FTD patients. Proteomics and functional studies illustrate corresponding reductions in mitochondrial components and compensatory increases in protein synthesis. Collectively, these observations suggest that TDP-43 deposition leads to targeted RNA instability in ALS and FTD, and may ultimately cause cell death by disrupting energy production and protein synthesis pathways.
Project description:Identification of amyotrophic lateral sclerosis (ALS) associated genes. Post mortem spinal cord grey matter from sporadic and familial ALS patients compared with controls. Keywords: other
Project description:Identification of familial amyotrophic lateral sclerosis (fALS) related genes. Material from three hSOD1(G93A) transgenic mice was compared to material from three non-transgenic control mice using an alternating loop design on two-colour cDNA microarrays. Statistical data management and analysis: postgreSQL relational database (www.postgresql.org), Perl, and R (www.r-project.org); pin-wise lowess-regression based normalisation (Yang et al., 2002 [PMID: 11842121]); mixed ANOVA-model. Keywords = amyotrophic lateral sclerosis, ALS, SOD1 mouse model
Project description:We have performed methylation microarray analysis of two types of dementia, Alzheimer's disease (AD) and frontotemporal dementia (FTD), using two kind of samples, frozen brain tissue and lymphoblastoid cell lines.