Project description:Here we analyse transcriptome profiles from laser captured lower motor neurons between wild type, heterozygous and homozygous TDP-43 Q331K knockin mice
Project description:Here we analyse transcriptome profiles within the frontal cortex between wild type, heterozygous and homozygous TDP-43 Q331K knockin mice at 20 months of age (C57BL/6)
Project description:Here we analyse transcriptome profiles within the frontal cortex between wild type, heterozygous and homozygous TDP-43 Q331K knock-in mice
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:The aim of this study is to understand the mechanisms of TDP-43 neurotoxicity. Here, we perform a RNA-Seq analysis in TDP-43 gain-of-fucntion (GOF) , TDP-43 loss-of-function and wild-type late pupae heads (73-90 hours APF) and perform TDP-43 GOF vs wild type and TDP-43 LOF vs wild-type differential expression analysis to show that both mechanisms presents defects in ecdysone receptor (ECR)-dependeint transcriptional program switching, and strongly deregulate expression from the neuronal microtubule associated protien Map205. RNA-seq was performed in two wild-type D.melanogaster biological replicates (Canton S, w1118 ), four biological replicates for TDP-43 (LOF) with two distinct genotypes (dTDP-43Δ142/Df(2R)106,dTDP-43Δ23/Δ142 ) and two TDP-43 GOF biological replicates (act5c>dTDP-43 ).
Project description:TAR DNA-binding protein 43 (TDP-43) is normally a nuclear RNA-binding protein that exhibits a range of functions including regulation of alternative splicing, RNA trafficking and RNA stability. However, in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with TDP-43 inclusions (FTLD-TDP), TDP-43 is abnormally phosphorylated, ubiquitinated, and cleaved, and is mislocalized to the cytoplasm where it forms distinctive aggregates. We previously developed a mouse model expressing human TDP-43 with a mutation in its nuclear localization signal (ΔNLS-hTDP-43) so that the protein preferentially localizes to the cytoplasm. These mice did not exhibit a significant number of cytoplasmic aggregates, but did display a loss of endogenous mouse nuclear TDP-43 as well as dramatic changes in gene expression as measured by microarray. Here, we analyze RNA-sequencing data from the ∆NLS-hTDP-43 mouse model, together with published RNA-sequencing data obtained previously from TDP-43 antisense oligonucleotide (ASO) knockdown mice and High Throughput Sequencing of RNA isolated by CrossLinking ImmunoPrecipitation (HITS-CLIP) data of TDP-43’s RNA binding targets to further investigate the dysregulation of gene expression in the ∆NLS model. This analysis reveals that the transcriptomic effects of the overexpression of the ΔNLS-hTDP-43 transgene are likely due to a gain of cytoplasmic function. Moreover, cytoplasmic TDP-43 expression alters transcripts that regulate chromatin assembly, the nucleolus, lysosomal function, and histone 3’ untranslated region (UTR) processing. These transcriptomic alterations correlate with observed histologic abnormalities in heterochromatin structure and nuclear size in transgenic mouse and human brains.
Project description:We identify the RNA targets of TAR DNA-binding protein 43 (TDP-43) from cortical neurons by RNA immunoprecipitation followed by deep sequencing (RIP-seq). We identify 4352 highly enriched RNA targets of TDP-43. We determined that the canonical TDP-43 binding site (TG)n was 55.1-fold enriched in our TDP-43 library. Moreover, our analysis shows there is often an adenine in the middle of the motif, (TG)nTA(TG)m. TDP-43 RNA targets are particularly enriched for Gene Ontology terms related to RNA metabolism, neuronal development, and synaptic function. Examination of TDP-43 RNA targets in rat cortical neurons by RIP-seq. Chantelle F. Sephton isolated the TDP-43:RNA complexes and generated the cDNA library for deep sequencing. Email: chantelle.sephton@utsouthwestern.edu Phone: 214-648-4119 Fax: 214-648-1801 ULR: http://www8.utsouthwestern.edu/utsw/cda/dept120915/files/151135.html Organization name: University of Texas Southwestern Medical Center at Dallas Department: Neuroscience Lab: Gang Yu lab Street: 6000 Harry Hines Blvd. City: Dallas State: Texas ZIP: 75390 Country: USA