Project description:RNA abundance decreases linearly from the 5′ to 3′ end of long introns to create “saw-tooth” patterns, and these can be used to infer locations of major splicing events. FUS binds across entire pre-mRNAs with limited sequence specificity, permitting examination of these saw-tooth patterns. We used FUS iCLIP from the human brain to identify deviations from the expected linear decrease of reads across long introns that correspond to recursive splicing events. iCLIP protocol was followed to isolate RNA bound to FUS protein and amplify cDNA library as described in the manuscript. Specific barcodes were used for each RT reaction, and are specified in the library construction protocol for each sequencing run. Random barcodes were also incorporated into cDNAs to distinguish between PCR duplication of cDNA products. The final products were obtained by PCR with Illumina paired-end sequencing primers: 5-CAAGCAGAAGACGGCATACGAGATCGGTCTCGGCATTCCTGCTGAACCGCTCTTCCGATCT-3; 5-AATGATACGGCGACCACCGAGATCTACACTCTTTCCCTACACGACGCTCTTCCGATCT-3
Project description:FUS is a primarily nuclear RNA-binding protein with important roles in RNA processing and transport. FUS mutations disrupting its nuclear localization characterize a subset of amyotrophic lateral sclerosis (ALS-FUS) patients, through an unidentified pathological mechanism. FUS regulates nuclear RNA, but its role at the synapse is poorly understood. Here, we used super-resolution imaging to determine the physiological localization of extranuclear, neuronal FUS and found it predominantly near the vesicle reserve pool of presynaptic sites. Using CLIP-seq on synaptoneurosome preparations, we identified synaptic RNA targets of FUS that are associated with synapse organization and plasticity. Synaptic FUS was significantly increased in a knock-in mouse model of ALS-FUS, at presymptomatic stages. Despite apparently unaltered synaptic organization, RNA-seq of synaptoneurosomes highlighted age-dependent dysregulation of glutamatergic and GABAergic synapses. Our study indicates that FUS relocalization to the synapse in early stages of ALS-FUS results in synaptic impairment, potentially representing an initial trigger of neurodegeneration.
Project description:Total RNA was extracted from wild-type and FUS -/- mouse E18 brain samples using RNeasy kit, cDNA was synthesized using GeneChip WT cDNA Synthesis and Amplification kit (Affymetrix 900673) and hybridised to Affymetrix mouse high-resolution AltSplice microarrays.
Project description:UV cross-linking and immunoprecipitation (CLIP) and individual-nucleotide resolution CLIP (iCLIP) are the most frequently used methods to study protein-RNA interactions in the intact cells and tissues, but their relative advantages or inherent biases have not been evaluated. To benchmark CLIP and iCLIP method, we performed iCLIP with Nova protein, which is the most extensively studied protein by CLIP. Further, we assessed UV-C-induced cross-linking preferences, by exploiting the UV-independent formation of covalent RNA cross-links of the mutant RNA methylase NSUN2.
Project description:We identified a landscape of FUS-binding RNA targets in HeLa cells. The majority of the FUS binding sites are in introns of pre-mRNAs and less are in exons and untranslated regions. Significant FUS binding in introns flanking cassette exons, long intron (>100kb) containing transcripts and noncoding RNAs were detected in our study. We specifically determined the function of FUS in regulating the alternative splicing of cassette exons. The top FUS-associated cassette exon is exon 7 of the pre-mRNA of FUS itself. We demonstrated that FUS is a repressor of its own exon 7 splicing. FUS autoregulates its own protein levels by exon 7 alternative splicing and nonsense mediated decay. Moreover, Amyotrophic Lateral Sclerosis (ALS) linked FUS mutants are deficient in FUS autoregulation. CLIP-seq of FUS in HeLa cells
Project description:FUS, an RNA binding protein was recently implicated in Amyotrophic Lateral Sclerosis (ALS). ALS is a fatal neurodegenerative disease. We report the identification of the conserved neuronal RNA targets of FUS and the assessment of the impact of FUS depletion on the neuronal transcriptome. We identified that FUS regulates splicing of conserved intron containing transcripts. FUS retains or excludes the conserved intron by binding to them. Identification of FUS neuronal targets using normal human brain samples and mouse neurons
Project description:To clarify the functional properties of FUS, we established the differentially expressed alternative exons in FUS-silenced primary cortical neurons by using exon-sensitive microarray technology. We analyzed total RNA of primary cortical neuron infected with lentivirus expressing shRNA against mouse Fus or control. RNA was harvested 11 days after transfection.
Project description:TDP-43, FUS, and TAF15 are implicated in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. We integrate CLIP-seq and RNA Bind-N-Seq technologies to discover that TAF15 binds to ~4,900 RNAs enriched for GGUA motifs. In the mouse brain, TAF15 and FUS, but not TDP-43, exhibit strikingly similar RNA binding profiles, yet they alter the expression of distinct mRNA populations upon their individual depletions. TAF15 has a minimal role in alternative splicing and instead affects RNA turnover, consistent with an enrichment of TAF15 binding sites in 3â?? untranslated regions. In human stem cell-derived motor neurons, loss of both TAF15 and FUS affected mRNAs distinct from those altered by loss of either protein alone, revealing redundant roles for TAF15 and FUS in maintaining mRNA levels. Furthermore, concomitant rather than individual depletion of TAF15 and FUS more closely resembles RNA profiles of motor neurons derived from FUS R521G ALS patients or from late-stage, sporadic ALS patients. Our study reveals convergent and divergent mechanisms by which FUS, TAF15 and TDP-43 affects RNA metabolism in neurological disease. RNA-seq, CLIP-seq and arrays in mouse and human against TAF15 knockdowns This Series represents CLIP-seq sample(s).
Project description:The protein Fused in Sarcoma undergoes liquid-liquid phase separation. To investigate whether this phase transition alters the RNA interactome we purified phase-separated FUS droplets and soluble FUS from HEK 293T cells transfected with GFP-tagged WT FUS or P525L FUS. Phase separated FUS was purified by fluorescence-activated particle sorting (droplets) and soluble FUS by co-Immunoprecipitation (IP) respectively followed by isolation of co-purified RNA. Here we show that phase separation affects the RNA interactome of FUS.