Comparison of poly(A) and capture RNA-seq: controlled degradation in vitro
ABSTRACT: We compare the performance of two library preparation protocols (poly(A) and exome capture) in in vitro degraded RNA samples VcaP cell were grown, and treated with MDV3100 (enzalutamide) or DHT (dihydrotestosterone), intact RNA was isolated and samples were prepared in technical triplicates using two library preparation protocol. Also cells were subject to in vitro degradation through incubation of the whole cell lysate in 37C for increasing amounts of time. Following incbation paired capture and poly(A) libraries were prepared.
Project description:Illumina gene array analyses of prostate cancer cell lines that had acquired resistance to Enzalutamide (MDV3100). mRNA analyses of four cell lines (CWR-R1, LAPC-4, LNCaP, and VCAP) cells that were either untreated, treated for 48hrs with Enz (short-term), or continuously grown in Enzalutamide for >6 months.
Project description:Novel RNA-guided cellular functions are paralleled by an increasing number of RNA binding proteins (RBPs). We present “serial interactome capture” (serIC), a multiple purification procedure of UV-crosslinked poly(A)-RNA-protein complexes that enables global RBP detection with maximal specificity. We apply serIC to nuclei of proliferating K562 cells to obtain the first human nuclear interactome. The domain composition of the 382 identified nuclear RBPs markedly differs from previous IC experiments, including fewer factors without known RNA binding domains that are in better agreement with computationally predicted RNA binding. serIC extends the number of DNA-RNA binding proteins (DRBPs), and reveals a network of RBPs involved in p53 signaling and double strand break repair. serIC is an effective tool to couple global RBP capture with additional selection or labelling steps for specific detection of highly purified RBPs. The nuclear interactome presented here is a stepping-stone towards deciphering of the functional RNA-protein network in the mammalian nucleus.
Project description:We have used a combination of three high-throughput RNA capture and sequencing methods to refine and augment the transcriptome map of a well studied genetic model, Caenorhabditis elegans. The three methods include a standard (non-directional) library preparation protocol relying on cDNA priming and foldback that has been used in several previous studies for transcriptome characterization in this species, and two directional protocols, one involving direct capture of single stranded RNA fragments and one involving circular-template PCR (circligase). We find that each RNA-seq approach shows specific limitations and biases, with the application of multiple methods providing a more complete map than was obtained from any single method. Of particular note in the analysis were substantial advantages of circligase-based and ssRNA-based capture for defining sequences and structures of the precise 5' ends (which were lost using the double strand cDNA capture method). Of the three methods, ssRNA capture was most effective in defining sequences to the polyA junction. Using datasets from a spectrum of C. elegans strains and stages and the UCSC Genome Browser, we provide a series of tools, which facilitate rapid visualization and assignment of gene structures. single-strand-capture, double-strand-capture, and circligase-based RNA-seq
Project description:RNA isolation and RNA-Seq: Wild-type Xcc or pXccBphP strains were cultured in far-red light or dark conditions up to logarithmic phase (0.7 to 0.8 OD600) at 28C in PYM broth. Total bacterial RNA was isolated using the MasterPureTM RNA Purification Kit (Epicentre, Illumina). Samples corresponding to two biological replicates of each condition were submitted to Genome Qubec for rRNA removal with Ribo-Zero (Illumina) and TruSeq RNA-seq library preparation. 50 bp single-end sequencing of the libraries was performed using an Illumina HiSeq 2000 platform (Genome Qubec). Removal of low-quality reads and Illumina adapters, and assessment of the quality of the reads was performed using Trimmomatic (Bolger et al, 2014) and FastQC (www.bioinformatics.babraham.ac.uk/ projects/fastqc/), respectively. Rads were aligned to the Xcc genome obtained from GenBank (accession number: NC_007086.1) using SAMtools and the BurrowsWheeler Alignment software (BWA) (Li et al, 2009). Alignments were visualized using the software Integrated Genome Viewer (IGV) (http://broadinstitute.org/igv). RNA-Seq differential expression analysis: Read counts corresponding to annotated ORFs were quantified with the software FeatureCounts (Liao et al, 2014) using the strand specific mode. Differential expression analysis was performed using the software DESeq (Anders & Huber, 2010). Genes displaying adjusted p-value < 0.05.
Project description:Prostate cancer is the most commonly diagnosed and second-most lethal cancer among men in the United States. The vast majority of prostate cancer deaths are due to castration-resistant prostate cancer (CRPC) – the lethal form of the disease that has progressed despite therapies that interfere with activation of androgen receptor (AR) signaling. One emergent resistance mechanism to medical castration is synthesis of intratumoral androgens that activate the AR. This insight led to the development of the AR antagonist enzalutamide. However, resistance to enzalutamide invariably develops, and disease progression is nearly universal. One mechanism of resistance to enzalutamide is an F877L mutation in the AR ligand-binding domain that can convert enzalutamide to an agonist of AR activity. However, mechanisms that contribute to the agonist switch had not been fully clarified, and there were no therapies to block AR F877L. Using cell line models of castration-resistant prostate cancer (CRPC), we determined that cellular androgen content influences enzalutamide agonism of mutant F877L AR. Further, enzalutamide treatment of AR F877L-expressing cell lines recapitulated the effects of androgen activation of F877L AR or wild-type AR. Because the BET bromodomain inhibitor JQ-1 was previously shown to block androgen activation of wild-type AR, we tested JQ-1 in AR F877L-expressing CRPC models. We determined that JQ-1 suppressed androgen or enzalutamide activation of mutant F877L AR and suppressed growth of mutant F877L AR CRPC tumors in vivo, demonstrating a new strategy to treat tumors harboring this mutation. RNA-seq profiles of prostate cancer cell lines to understand gene expression associated with enzalutamide treatment
Project description:Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) patients with the C9orf72 mutation show predominantly cytoplasmic aggregates of poly-GR and poly-PR proteins that are acutely toxic in various model systems. To identify the molecular mediators of neurotoxicity of poly-GR/PR, we analyzed their interactomes in primary neurons. GFP-(GR)149 and (PR)175-GFP preferentially interacted with RNA-binding proteins, including stress granule-associated and nucleolar proteins, as well as ribosomes. Overexpression of the poly-GR/PR interactors Staufen 1/2 (STAU1/2) and YBX1 led to cytoplasmic aggregation of poly-GR/PR into large stress granule-like inclusions, while the poly-GR/PR interactor nucleophosmin (NPM1) recruited poly-GR into the nucleolus. In addition, poly-PR expression reduced ribosome levels and translation, which is consistent with the widespread reduction of synaptic proteins detected by proteomics. Surprisingly, only GFP-(GR)53, but not GFP-(GR)149, localized to the nucleolus and reduced ribosome levels and translation in neurons, suggesting impaired ribosome biogenesis is driving the acute toxicity commonly observed in vitro. In C9orf72 patient brains, we detected co-aggregation of poly-GR/PR inclusions with ribosomes, but not stress granules. Partial sequestration of ribosomes may chronically impair protein synthesis and contribute to C9orf72 ALS/FTD pathogenesis.
Project description:We provide raw gene sequences of 174 flowering time regulatory genes and gene othologs across a large barley population (895 barley lines) selected from a collection of landrace, cultivated barley, and research varieties of diverse origin. This set represents the whole variety of cultivated barley lifeforms, namely two- and six-row genotypes with winter, spring, and facultative growth habits. We applied a target capture method based on in-solution hybridization using the myBaits® technology (Arbor Biosciences, Ann Arbour, MI, USA) which is based on in-solution biotinylated RNA probes. Baits were designed for flowering time regulatory genes and gene othologs, and used for production of 80mer capture oligonucleotides for hybridization. Genomic DNA was extracted from leaves of a single two-week old barley plant per variety using the cetyl-trimethyl-ammonium bromide (CTAB) method. Physical shearing of genomic DNA was performed with an average size of 275 bp. Library preparation was conducted with KAPA Hyper Prep Kit (KAPA Biosystems, Wilmington, MA). Hybridization of customised RNA baits with capture pools was performed at 65°C for 24 hours. Each pooled sequence capture library was sequenced on an Illumina HiSeq3000 instrument using three lanes to generate paired-end reads per sample. Genome sequencing was conducted at AgriBio, (Centre for AgriBioscience, Bundoora, VIC, Australia).
Project description:RNA-binding proteins (RBPs) have essential roles in RNA-mediated gene regulation, and yet annotation of RBPs is limited mainly to those with known RNA-binding domains. To systematically identify the RBPs of embryonic stem cells (ESCs), we here employ interactome capture, which combines UV cross-linking of RBP to RNA in living cells, oligo(dT) capture and MS. From mouse ESCs (mESCs), we have defined 555 proteins constituting the mESC mRNA interactome, including 283 proteins not previously annotated as RBPs. Of these, 68 new RBP candidates are highly expressed in ESCs compared to differentiated cells, implicating a role in stem-cell physiology. Two well-known E3 ubiquitin ligases, Trim25 (also called Efp) and Trim71 (also called Lin41), are validated as RBPs, revealing a potential link between RNA biology and protein-modification pathways. Our study confirms and expands the atlas of RBPs, providing a useful resource for the study of the RNA-RBP network in stem cells.
Project description:Removal of introns by pre-mRNA splicing is a critical and in some cases rate-limiting step in mammalian gene expression. Deep sequencing of mouse embryonic stem cell RNA revealed many specific internal introns that are significantly more abundant than the other introns within poly(A) selected transcripts; we classify these as “detained” introns (DIs). We identified thousands of DIs flanking both constitutive and alternatively spliced exons in human and mouse cell lines. Drug inhibition of Clk SR-protein kinase activity triggered rapid splicing changes in a specific set of DIs, about half of which showed increased splicing and half increased intron detention, altering the transcript pool of over 300 genes. These data suggest a widespread mechanism by which a nuclear detained pool of mostly processed pre-mRNAs can be rapidly mobilized in response to stress or homeostatic autoregulation. v6.5 mouse embryonic stem cells were untreated, treated with the Clk kinase inhibitor KH-CB19, or treated with DMSO as a negative control. Untreated cells were harvested and a single replicate was sequenced using a custom, ligation-based, stranded library preparation protocol. Treated cells were harvested at time 0 and at 2 hours post-treatment, and poly(A)-selected RNA-seq libraries were made from biological duplicates for each treatment/time, barcoded, and sequenced by strand-specific, paired-end sequencing using the Illumina TruSeq kit.