Hsp90 is critical for regulation of the phenotype and functional activity of human T lymphocytes and natural killer (NK) cells.
Heat shock protein 90 is critical for regulation of phenotype and functional activity of human T lymphocytes and NK cells.
Specimen part, Treatment
View SamplesImmunodeficient mouse models have been valuable for studies of human hematopoiesis, but high-fidelity recapitulation of erythropoiesis in most xenograft recipients remains elusive. Recently developed immunodeficient and Kit mutant mice, however, have provided a suitable background to achieve higher-level human erythropoiesis after long-term hematopoietic engraftment. While there has been some characterization of human erythropoiesis in these models, a comprehensive analysis of various developmental stages has not yet been reported. Here, we have utilized cell surface phenotypes, morphologic analyses, and molecular studies to fully characterize human erythropoiesis from multiple developmental stages in immunodeficient and Kit mutant mouse models following long-term hematopoietic stem and progenitor cell engraftment. We show that human erythropoiesis in such models demonstrates complete maturation and enucleation, as well as developmentally appropriate globin gene expression. These results provide a framework for future studies to utilize this model system for interrogating disorders affecting human erythropoiesis and for developing improved therapeutic approaches. Overall design: (mRNA-seq) RNA-seq of human CD235a+ cells isolated 14-16 weeks post-implantation from mouse bone marrow were performed for three biological replicates each of mice xenograted with adult bone marrow-derived human CD34+ cells and cord blood-derived CD34+ cells.
Developmentally-faithful and effective human erythropoiesis in immunodeficient and Kit mutant mice.
Specimen part, Subject
View SamplesProtein-RNA interactions are fundamental to core biological processes, such as mRNA splicing, localization, degradation and translation. We have developed a photoreactive nucleotide-enhanced UV crosslinking and oligo(dT) purification approach to identify the mRNA-bound proteome using quantitative proteomics and to display the protein occupancy on mRNA transcripts by next-generation sequencing (Baltz and Munschauer et al. 2012). Our current work focuses on streamlining and extending protein occupancy profiling on poly(A)-RNA. Our objectives are to identify previously unknown protein-bound transcripts and, more importantly, to assess global and local differences in protein occupancy across different biological conditions. To this end, we have implemented poppi, the first pipeline for differential analysis of protein occupancy profiles. We have applied our analysis pipeline to pinpoint changes in occupancy profiles of MCF7 cells against already published HEK293 cells [GSE38157]. Overall design: We generated protein occupancy cDNA libraries for two biological replicates. Briefly, we crosslinked 4SU-labeled MCF7 cells and purified protein-mRNA complexes using oligo(dT)-beads. The precipitate was treated with RNAse I to reduce the protein-crosslinked RNA fragments to a length of about 30-60 nt. To remove non-crosslinked RNA, protein-RNA complexes were precipitated with ammonium sulfate and blotted onto nitrocellulose. The RNA was recovered by Proteinase K treatment, ligated to cloning adapters, and reverse transcribed. The resulting cDNA libraries were PCR-amplified and next-generation sequenced.
Differential protein occupancy profiling of the mRNA transcriptome.
No sample metadata fields
View SamplesRNA helicases are important regulators of gene expression that act by remodeling RNA secondary structures and as RNA-protein interactions. Here, we demonstrate that MOV10 has an ATP-dependent 5'' to 3'' in vitro RNA unwinding activity and determine the RNA-binding sites of MOV10 and its helicase mutants using PAR-CLIP. We find that MOV10 predominantly binds to 3'' UTRs upstream of regions predicted to form local secondary structures and provide evidence that MOV10 helicase mutants are impaired in their ability to translocate 5'' to 3'' on their mRNA targets. MOV10 interacts with UPF1, the key component of the nonsense-mediated mRNA decay pathway. PAR-CLIP of UPF1 reveals that MOV10 and UPF1 bind to RNA in close proximity. Knockdown of MOV10 resulted in increased mRNA half-lives of MOV10-bound as well as UPF1-regulated transcripts, suggesting that MOV10 functions in UPF1-mediated mRNA degradation as an RNA clearance factor to resolve structures and displace proteins from 3'' UTRs. Overall design: Flp-In T-REx HEK293 cells expressing FLAG/HA-tagged MOV10 WT, MOV10 K530A, MOV10 D645N and UPF1 were used to determine the protein-RNA interaction sites of RNA helicases MOV10 and UPF1 as well as MOV10 inactive variants using PAR-CLIP in combination with next generation sequencing. mRNA half-life changes of MOV10-targeted mRNA were determined by measuring mRNA half-lives by mRNA sequencing of mock and MOV10-depleted HEK293 cells.
MOV10 Is a 5' to 3' RNA helicase contributing to UPF1 mRNA target degradation by translocation along 3' UTRs.
No sample metadata fields
View SamplesThe conserved human LIN28 RNA-binding proteins function in development, maintenance of pluripotency and oncogenesis. We used PAR-CLIP and a newly developed variant of this method, iDo-PAR-CLIP, to identify LIN28B targets as well as sites bound by the individual RNA binding domains of LIN28B in the human transcriptome at nucleotide resolution. The position of target binding sites reflected the known structural relative orientation of individual LIN28B binding domains, validating iDo-PAR-CLIP. Our data suggest that LIN28B directly interacts with most expressed mRNAs and members of the let-7 microRNA family. The Lin28 binding motif detected in pre-let-7 was enriched in mRNA sequences bound by LIN28B. Upon LIN28B knock down, cell proliferation and the cell cycle were strongly impaired. Quantitative shotgun proteomics of LIN28B depleted cells revealed significant reduction of protein synthesis from its RNA targets that function in translation, mRNA splicing and cell cycle control. Computational analyses provided evidence that the strength of protein synthesis reduction correlated with the location of LIN28B binding sites within target transcripts. Overall design: We used PAR-CLIP and a newly developed variant of this method, iDo-PAR-CLIP, to identify LIN28B targets as well as sites bound by the individual RNA binding domains of LIN28B in the human transcriptome at nucleotide resolution.
Identification of LIN28B-bound mRNAs reveals features of target recognition and regulation.
Cell line, Subject
View SamplesRoom temperature whole blood mRNA stabilization procedures, such as the PAX gene system, are critical for the application of transcriptional analysis to population-based clinical studies. Global transcriptome analysis of whole blood RNA using microarrays has proven to be challenging due to the high abundance of globin transcripts that constitute 70% of whole blood mRNA in the blood. This is a particular problem in patients with sickle-cell disease, secondary to the high abundance of globin-expressing nucleated red blood cells and reticulocytes in the circulation . In order to more accurately measure the steady state whole blood transcriptome in sickle-cell patients, we evaluated the efficacy of reducing globin transcripts in PAXgene stabilized RNA samples for genome-wide transcriptome analyses using oligonucleotide arrays. We demonstrate here by both microarrays and Q-PCR that the globin mRNA depletion method resulted in 55-65 fold reduction in globin transcripts in whole blood collected from healthy volunteers and sickle-cell disease patients. This led to an improvement in microarray data quality with increased detection rate of expressed genes and improved overlap with the expression signatures of isolated peripheral blood mononuclear (PBMC) preparations. The differentially modulated genes from the globin depleted samples had a higher correlation coefficient to the 112 genes identified to be significantly altered in our previous study on sickle-cell disease using PBMC preparations. Additionally, the analysis of differences between the whole blood transcriptome and PBMC transcriptome reveals important erythrocyte genes that participate in sickle-cell pathogenesis and compensation. The combination of globin mRNA reduction after whole-blood RNA stabilization represents a robust clinical research methodology for the discovery of biomarkers for hematologic diseases and in multicenter clinical trials investigating a wide range of nonhematologic disorders where fractionation of cell types is impracticable.
Characterization of whole blood gene expression profiles as a sequel to globin mRNA reduction in patients with sickle cell disease.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
FMRP targets distinct mRNA sequence elements to regulate protein expression.
Cell line
View SamplesCircuit neuroscience has made great progress by linking neuronal function to marker gene expression, allowing the specific investigation of otherwise indistinguishable neuronal ensembles. Here, we performed next generation sequencing on two functionally and genetically distinct interneuronal populations marked by the expression of protein kinase C d (PKCd) or somatostatin (SST) in the central amygdala (CEA) of mice, which are known to play distinct and sometimes opposing roles in emotion processing. Making their gene expression profile known will aid in forming hypotheses of how different neurotransmitters or psychoactive drugs could alter information processing in these neurons. Overall design: Unchallenged gene expression profile of two different neuronal populations in the central amygdala
Dorsal tegmental dopamine neurons gate associative learning of fear.
Sex, Specimen part, Subject
View SamplesFragile-X Syndrome (FXS) is a multi-organ disease leading to mental retardation, macro-orchidism in males, and premature ovarian insufficiency in female carriers. FXS is also a prominent monogenic disease associated with autism spectrum disorders (ASD). FXS is typically caused by the loss of FRAGILE X-MENTAL RETARDATION 1 (FMR1) expression, which encodes for the RNA-binding protein (RBP), FMR1 (or FMRP). We report the discovery of the RNA recognition elements (RREs), binding sites, and mRNA targets for wild-type and I304N mutant FMRP isoforms as well as its paralogs, FXR1 and FXR2. RRE frequency, ratio, and distribution determine target mRNA association with FMRP. Among highly-enriched targets, we identified many genes involved in ASD and demonstrate that FMRP can affect their protein levels in cell culture, mice, and human brain. Unexpectedly, we discovered that these targets are also dysregulated in Fmr1-/- mouse ovaries, showing signs of premature follicular overdevelopment. These results indicate that FMRP targets shared signaling pathways across different cellular contexts. As it is become increasingly appreciated that signaling pathways are important to FXS and ASD, our results here provide an invaluable molecular guide towards the pursuit of novel therapeutic targets for these devastating neurological disorders.
FMRP targets distinct mRNA sequence elements to regulate protein expression.
Cell line
View SamplesThousands of long non-coding RNAs (lncRNAs) have been identified in the human genome, but specific biological functions and biochemical mechanisms have been discovered for only about a dozen lncRNAs. One specific lncRNA, Non-coding RNA Activated by DNA Damage (NORAD), has recently been shown by genetic deletion to be required for maintaining genomic stability, but its molecular mechanism is unknown. Here, we combine RNA antisense purification (RAP) and quantitative mass spectrometry to identify proteins that directly interact with NORAD in living cells. We show that NORAD interacts with proteins involved in DNA replication and repair in steady-state cells and localizes to the nucleus upon stimulation with replication stress or DNA damage. In particular, NORAD interacts with RBMX (an emerging component of the DNA-damage response) and encodes the strongest RBMX-binding site in the transcriptome. We demonstrate that NORAD controls the ability of RBMX to assemble a ribonucleoprotein complex, which we term NORAD-Activated Ribonucleoprotein Complex 1 (NARC1), containing known suppressors of genomic instability: topoisomerase I (TOP1), ALYREF and the PRPF19/CDC5L complex. Cells depleted of NORAD or RBMX display an increased frequency of chromosome segregation errors, reduced replication-fork velocity and altered cell cycle progression phenotypes that are mechanistically linked to TOP1 and PRPF19/CDC5L function. Expression of NORAD in trans can rescue defects caused by NORAD depletion, but rescue is significantly impaired when the RBMX-binding site in NORAD is deleted. Our results demonstrate that the interaction between NORAD and RBMX is important for NORAD function and that NORAD is required for the assembly of a previously unknown topoisomerase complex (NARC1) that contributes to maintaining genomic stability. Moreover, we uncover a novel function for lncRNAs in modulating the ability of an RNA-binding protein to assemble a higher-order ribonucleoprotein complex. Overall design: We examined gene expression changes and alternative splicing events in wildtype and NORAD depleted cells using RNA sequencing.
The NORAD lncRNA assembles a topoisomerase complex critical for genome stability.
Cell line, Subject, Time
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