mRNA expression differences between the liver and kidney of an adult male (homo sapien) were investigated using three technical replicates.
RNA-seq: an assessment of technical reproducibility and comparison with gene expression arrays.
No sample metadata fields
View SamplesIdentification of genetic polymorphisms associated with inter-individual variation in immune response to Mycobacterium tuberculosis infection.
Deciphering the genetic architecture of variation in the immune response to Mycobacterium tuberculosis infection.
Sex
View SamplesNext-generation sequencing has become an important tool for genome-wide quantification of DNA and RNA. However, a major technical hurdle lies in the need to map short sequence reads back to their correct locations in a reference genome. Here we investigate the impact of SNP variation on the reliability of read-mapping in the context of detecting allele-specific expression (ASE).We generated sixteen million 35 bp reads from mRNA of each of two HapMap Yoruba individuals. When we mapped these reads to the human genome we found that, at heterozygous SNPs, there was a significant bias towards higher mapping rates of the allele in the reference sequence, compared to the alternative allele. Masking known SNP positions in the genome sequence eliminated the reference bias but, surprisingly, did not lead to more reliable results overall. We find that even after masking, $\sim$5-10\% of SNPs still have an inherent bias towards more effective mapping of one allele. Filtering out inherently biased SNPs removes 40\% of the top signals of ASE. The remaining SNPs showing ASE are enriched in genes previously known to harbor cis-regulatory variation or known to show uniparental imprinting. Our results have implications for a variety of applications involving detection of alternate alleles from short-read sequence data. Scripts, written in Perl and R, for simulating short reads, masking SNP variation in a reference genome, and analyzing the simulation output are available upon request from JFD. Overall design: RNA-Seq on two YRI Hapmap cell lines. Each individual sequenced on two lanes of the Illumina Genome Analyzer
Effect of read-mapping biases on detecting allele-specific expression from RNA-sequencing data.
No sample metadata fields
View SamplesUnderstanding the genetic mechanisms underlying natural variation in gene expression is a central goal of both medical and evolutionary genetics, and studies of expression quantitative trait loci (eQTLs) have become an important tool for achieving this goal. While all eQTL studies to date have assayed mRNA levels using expression microarrays, recent advances in RNA sequencing enable the analysis of transcript variation at unprecedented resolution. We sequenced RNA from 69 lymphoblastoid cell lines (LCLs) derived from unrelated Nigerian individuals that have been extensively genotyped by the International HapMap Project. Pooling data from all individuals, we generated a map of the transcriptional landscape of these cells, identifying extensive use of unannotated polyadenylation sites and over 100 novel putative protein-coding exons. Using the genotypes from the HapMap project, we identified over a thousand genes at which genetic variation influences overall expression levels or splicing. We demonstrate that eQTLs near genes generally act via a mechanism involving allele-specific expression, and that variation that influences the inclusion of an exon is enriched within or near the consensus splice sites. Our results illustrate the power of high-throughput sequencing for the joint analysis of variation in transcription, splicing, and allele-specific expression across individuals. Overall design: RNA-Seq in 69 lymphoblastoid cell lines from multiple Yoruban HapMap individuals in at least two replicate lanes per individual
Understanding mechanisms underlying human gene expression variation with RNA sequencing.
No sample metadata fields
View SamplesThis study explores lineage and regulatory processes involved in early post implantation mouse embryos using single-cell RNA-seq Overall design: Single cells from C57Bl/6Babr mouse embryos at E3.5, E4.5, E5.5 and E6.5 were isolated and subjected to single-cell RNA-seq protocol.
Single-Cell Landscape of Transcriptional Heterogeneity and Cell Fate Decisions during Mouse Early Gastrulation.
Specimen part, Cell line, Subject
View SamplesEye development is a multistep process that requires specific inductive signals and precise morphogenetic movements, starting early during development in the eye-field, a well-definite region of the anterior neural plate. It has been demonstrated that a gene network of eye field transcription factors (EFTFs) contributes to specify the neural and retinal fate of the eye field. Among these EFTFs, Xrx1 is involved in proliferation and neurogenesis in the eye field and is necessary for the correct development of the retina.
Brief report: Rx1 defines retinal precursor identity by repressing alternative fates through the activation of TLE2 and Hes4.
Specimen part
View SamplesPeripherally derived macrophages infiltrate the brain after bone marrow transplantation and during central nervous system (CNS) inflammation. It was initially suggested that these engrafting cells were newly derived microglia and that irradiation was essential for engraftment to occur. However, it remains unclear whether brain-engrafting macrophages (beMfs) acquire a unique phenotype in the brain, whether long-term engraftment may occur without irradiation, and whether brain function is affected by the engrafted cells. In this study, we demonstrate that chronic, partial microglia depletion is sufficient for beMfs to populate the niche and that the presence of beMfs does not alter behavior. Furthermore, beMfs maintain a unique functional and transcriptional identity as compared with microglia. Overall, this study establishes beMfs as a unique CNS cell type and demonstrates that therapeutic engraftment of beMfs may be possible with irradiation-free conditioning regimens. Overall design: Microglia were isolated from the brains of adult male c57BL/6 mice given bone marrow tranplants (BMT) with or without head shield. All mice received PLX5622 for 2 weeks, then placed and normal chow to recoever. Some mice were then challenged with LPS. Cells were isolated by MACS using CD11b magnetic beads.
Peripherally derived macrophages can engraft the brain independent of irradiation and maintain an identity distinct from microglia.
Age, Specimen part, Cell line, Treatment, Subject
View SamplesThis dataset describe the transcriptomic profiling of cecum, stomach and ileum from wild type, cdx2 conditional knock out and cdx2 ; apc deficient mice, by mRNA-seq. Each condition was analyzed in triplicated experiment to analyze the role of cdx2 in colorectal cancer susceptibilities Overall design: Biological samples from dissected tissue were tested by RNASeq in triplicates resulting into a total of 24 samples.
The Cdx2 homeobox gene suppresses intestinal tumorigenesis through non-cell-autonomous mechanisms.
Specimen part, Treatment, Subject
View SamplesPeripherally derived macrophages infiltrate the brain after bone marrow transplantation and during central nervous system (CNS) inflammation. It was initially suggested that these engrafting cells were newly derived microglia and that irradiation was essential for engraftment to occur. However, it remains unclear whether brain-engrafting macrophages (beMfs) acquire a unique phenotype in the brain, whether long-term engraftment may occur without irradiation, and whether brain function is affected by the engrafted cells. In this study, we demonstrate that chronic, partial microglia depletion is sufficient for beMfs to populate the niche and that the presence of beMfs does not alter behavior. Furthermore, beMfs maintain a unique functional and transcriptional identity as compared with microglia. Overall, this study establishes beMfs as a unique CNS cell type and demonstrates that therapeutic engraftment of beMfs may be possible with irradiation-free conditioning regimens. Overall design: Mice were given 1000rad whole body irradiation, followed by bone marrow transplant with UBC-GFP bone marrow at 8 weeks of age. Engraftment was allowed to occur for 8 months, then engrafting macrophages and microglia were isolated from whole brains for RNA-Seq.
Peripherally derived macrophages can engraft the brain independent of irradiation and maintain an identity distinct from microglia.
Age, Specimen part, Cell line, Subject
View SamplesThe aim of this experiment was to investigate differential gene expression in splenocytes stimulated with BCG from nave and BCG vaccinated mice. The differences between nave and BCG vaccinated mice might indicate the mechanisms by which BCG vaccination confers an enhanced ability of splenocytes from BCG vaccinated mice to inhibit growth of BCG in splenocyte cultures as compared with splenocytes from naive animals.
Mycobacterial growth inhibition in murine splenocytes as a surrogate for protection against Mycobacterium tuberculosis (M. tb).
Sex, Age, Specimen part
View Samples