Project description:An arrayed library containing pooled siRNAs targeting 18,480 human genes (Dharmacon, Lafayette, CO) was screened as previously described (Roosing et al., 2015).Briefly, 384-well plates with optical bottom (Greiner Bio-One, Monroe, NC) were spotted with 1 μl of 0.5 μM siRNA. Reverse transfection was next performed using Lipofectamine RNAiMAX at the final siRNA concentration of 10 nM. Culture medium was replaced with DMEM 24 hrs after transfection and cells were incubated for additional 48 hrs before lysis in SDS buffer for downstream analysis. These siRNAs were distributed in 57 plates, and after screen, we pooled 4 bar-coded plates for sequencing per Illumina sequencing lane.
Project description:Disruption of alternative splicing frequently causes or contributes to human diseases and disorders. Consequently, there is a need for efficient and sensitive reporter assays capable of screening chemical libraries for compounds with efficacy in modulating important splicing events. Here, we describe a screening workflow employing dual Nano and Firefly luciferase alternative splicing reporters that affords highly efficient, sensitive, and linear detection of small molecule responses. Applying this system to a screen of ~95,000 small molecules, we identify compounds that selectively activate or repress a neuronal microexon network that is frequently disrupted in autism and overexpressed in neuroendocrine cancers. Remarkably, among the most potent and selective activating compounds are histone deacetylase (HDAC) inhibitors. We thus describe a high-throughput screening system for candidate splicing therapeutics, a resource of small molecule modulators of microexons, and insight into the mode of action and potential utility of HDAC inhibitors in the context of neurological disorders.
Project description:RNA secondary structures have been increasingly reported to serve critical regulatory roles in post-transcriptional gene regulation. RNA G-quadruplex secondary structures can serve as cis-elements to recruit splicing factors and regulate alternative RNA splicing. We recently showed that RNA G-quadruplexes play a critical regulatory role in regulating alternative splicing during the epithelial mesenchymal transition. Due to the critical role alternative splicing plays in human health and disease, an unmet need exists to identify small molecule modulators of alternative splicing. In this study, we performed high-throughput screening using a dual-output splicing reporter to identify small molecules capable of regulating alternative splicing by interacting with RNA secondary structure G-quadruplexes. We identify emetine and its analog cephaeline as small molecules that denature RNA G-quadruplexes in a sequence and location independent manner to modify alternative splicing. Transcriptome analysis reveals that treatment with emetine globally regulates alternative splicing, including events associated with exon-proximal G-quadruplexes. These data suggest a critical role for emetine and cephealine as splicing regulators with the selective ability to disrupt RNA G-quadruplex-associated alternative splicing in vivo.
Project description:We introduce a new high-throughput transcriptomics (HTTr) platform comprised of a collagen sandwich primary rat hepatocyte culture and the TempO-Seq assay for screening and prioritizing potential hepatotoxicants. We selected 14 chemicals based on their risk of drug-induced liver injury (DILI) and tested them in hepatocytes at two treatment concentrations. HTTr data was generated using the TempO-Seq whole transcriptome and S1500+ assays. The HTTr platform exhibited high reproducibility between technical replicates (r>0.9) but biological replication was greater for TempO-Seq S1500+ (r>0.85) than for the whole transcriptome (r>0.7). Reproducibility between biological replicates was dependent on the strength of transcriptional effects induced by a chemical treatment. Despite targeting a smaller number of genes, the S1500+ assay clustered chemical treatments and produced gene set enrichment analysis (GSEA) scores comparable to those of the whole transcriptome. Connectivity mapping showed a high-level of reproducibility between TempO-Seq data and Affymetrix GeneChip data from the Open TG-GATES project with high concordance between the S1500+ gene set and whole transcriptome. Taken together, our results provide guidance on selecting the number of technical and biological replicates and support the use of TempO-Seq S1500+ assay for a high-throughput platform for screening hepatotoxicants.
Project description:Population scale sweeps of viral pathogens, such as SARS-CoV-2, require high intensity testing for effective management. However, reliable systems affording parallel testing of thousands of patients for pathogen infection have not yet been routinely employed. Here we describe “Systematic Parallel Analysis of RNA coupled to Sequencing for Covid-19 screening” (C19-SPAR-Seq), a multiplexed, readily automated platform for SARS-CoV-2 detection capable of analyzing tens of thousands of patient samples in a single instrument run. To address strict requirements for control of assay parameters and output demanded by clinical diagnostics, we employed a control-based Precision-Recall and Receiver Operator Characteristics (coPR) analysis to assign run-specific quality control metrics. C19-SPAR-Seq coupled to coPR on a trial cohort of several hundred patients performed with a specificity of 100% and sensitivity of 91% on samples with low viral loads. Our study thus establishes the feasibility of employing C19-SPAR-Seq for the large-scale monitoring of SARS-CoV-2 and other pathogens.
Project description:Population scale sweeps of viral pathogens, such as SARS-CoV-2, require high intensity testing for effective management. However, reliable systems affording parallel testing of thousands of patients for pathogen infection have not yet been routinely employed. Here we describe “Systematic Parallel Analysis of RNA coupled to Sequencing for Covid-19 screening” (C19-SPAR-Seq), a multiplexed, readily automated platform for SARS-CoV-2 detection capable of analyzing tens of thousands of patient samples in a single instrument run. To address strict requirements for control of assay parameters and output demanded by clinical diagnostics, we employed a control-based Precision-Recall and Receiver Operator Characteristics (coPR) analysis to assign run-specific quality control metrics. C19-SPAR-Seq coupled to coPR on a trial cohort of several hundred patients performed with a specificity of 100% and sensitivity of 91% on samples with low viral loads. Our study thus establishes the feasibility of employing C19-SPAR-Seq for the large-scale monitoring of SARS-CoV-2 and other pathogens.