We used microarrays to detect the primary changes caused by the 'san' mutation in Roquin gene by comparing the gene expression profiles of naive (CD44lo) CD8+ T cell population.
Breakdown in repression of IFN-γ mRNA leads to accumulation of self-reactive effector CD8+ T cells.
Specimen part
View SamplesFollicular T-helper (TFH) cells are essential for germinal center (GC) responses. TFH localization in GCs is controlled by chemo-guidance cues and antigen-specific adhesion. Here we define an antigen-independent, contact-dependent, adhesive guidance system for TFH cells. Unusual for amoeboid cell migration, the system is composed of transmembrane plexin B2 (PlxnB2) molecule that is highly expressed by GC B cells and its transmembrane binding partner semaphorin 4C (Sema4C) that is upregulated on TFH cells. Instead of effectuating repulsion as a ligand, Sema4C serves as the receptor to sense PlxnB2 and bias TFH migration inward at the GC edge to penetrate the GC territory. The absence of PlxnB2 from the GC or Sema4C from TFH cells causes TFH accumulation along the GC border, impairs TFH -B cell interactions and is associated with defective plasma cell production and affinity maturation. Therefore, Sema4C and PlxnB2 regulate GC TFH recruitment and function and optimal antibody responses. Overall design: Plxnb2+/+ or Plxnb2-/- CFP-expressing MD4 B cells were co-transferred together with OT-II T cells into B6 recipients that were subsequently immunized with HEL-OVA subcutaneously. MD4 cells of the 7-AAD-CD19+IgD-GL7hiFashi GC phenotype were FACS-sorted from pooled draining lymph nodes on day 5. To conduct transcriptomic RNA-seq analyses on these cells, a protocol initially developed for single-cell RNA-seq (Tang et al., 2011) was modified to accommodate 400 sorted cells by doubling reaction volumes with extra buffers until the step for second strand DNA synthesis. Cells were directly sorted into the lysis buffer, and reverse transcription was carried out for individual sorts within 20 minutes after isolation to preserve sample integrity. SE-100 sequencing was conducted for all samples on a HiSeq 2500 sequencer (Illumina) at the Tsinghua. Sequence reads were aligned to the Mus musculus reference genome using TopHat2 and assembled by Cufflinks to calculate the FPKM for each transcript. Genes with an average read number of at least 1 were subjected to differential expression analysis by the DESeq2 software (Bioconductor) with a call threshold set at padj<0.1.
Plexin B2 and Semaphorin 4C Guide T Cell Recruitment and Function in the Germinal Center.
Specimen part, Cell line, Subject
View SamplesSelection of B cells subjected to hypermutation in germinal centres (GC) during T-dependent (TD) antibody responses yields memory cells and long-lived plasma cells that produce high affinity antibodies biased to foreign antigens rather than self-antigens. GC also form in T-independent (TI) responses to polysaccharide antigens but failed selection results in GC involution and memory cells are not generated. To date there are no markers that allow phenotypic distinction of T-dependent and T-independent germinal centre B cells. We have now compared the global gene expression of GC B cells purified from mice immunized with either TD or TI antigens and identified eighty genes that are differentially expressed in TD GC.
Axon growth and guidance genes identify T-dependent germinal centre B cells.
No sample metadata fields
View SamplesMale C57BL/6 mice were treated with ENU to generate single base substitutions, the variant genome sequences were breed to homozygosity in inbreeding pedigrees, and screened for antinuclear autoantibodies (ANA). The sanroque pedigree contained multiple progeny with ANA of mixed homogeneous nuclear and cytoplasmic immunofluorescence pattern by 12 weeks of age, due to an autosomal recessive gene variant. Comparison of the gene expression profile of CD4 cells from Sanroque to wild type was performed.
A RING-type ubiquitin ligase family member required to repress follicular helper T cells and autoimmunity.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Combinatorial recruitment of CREB, C/EBPβ and c-Jun determines activation of promoters upon keratinocyte differentiation.
Specimen part, Treatment
View SamplesCombinatorial recruitment of CREB, C/EBPb and Jun determines activation of promoters upon keratinocyte differentiation
Combinatorial recruitment of CREB, C/EBPβ and c-Jun determines activation of promoters upon keratinocyte differentiation.
Specimen part, Treatment
View SamplesGene expression array analysis component. Ligand-dependent transcription by the nuclear receptor glucocorticoid receptor (GR) is mediated by interactions with co-regulators. The role of these interactions in determining selective binding of GR to regulatory elements remains unclear. Recent findings indicate a large fraction of genomic GR binding coincides with chromatin that is accessible prior to hormone treatment, suggesting that receptor binding is dictated by proteins that maintain chromatin in an open state. Combining nucleolytic cleavage and chromatin immunoprecipitation with high-throughput sequencing, we identify the activator protein 1 (AP1) as a major partner for productive GR-chromatin interactions. AP1 is critical for GR-regulated transcription and recruitment to co-occupied regulatory elements, illustrating an extensive AP1-GR interaction network. Importantly, the maintenance of baseline chromatin accessibility facilitates GR recruitment and is dependent on AP1 binding. We propose a model where the basal occupancy of transcription factors act to prime chromatin and direct inducible transcription factors to select regions in the genome.
Transcription factor AP1 potentiates chromatin accessibility and glucocorticoid receptor binding.
Sex, Cell line, Treatment, Time
View SamplesStudies of the Xenopus organizer have laid the foundation for our understanding of the conserved signaling pathways that pattern vertebrate embryos during gastrulation. Here, we use this wealth of knowledge as leverage in the design and analysis of a genomic visualization of organizer-related gene transcription. Using ectopic expression of the two major activities of the organizer, BMP and Wnt inhibition, as well as endogenous tissues, we generate a focused set of samples that represent different aspects of organizer signaling. The genomic expression values of each sample are then measured with oligonucleotide arrays. From this data, genes regulated by organizer signaling are selected and then clustered by their patterns of regulation. A new GO biological process annotation of the Xenopus genome allows us to rapidly identify clusters that are highly enriched for known gastrula patterning genes. Within these clusters, we can predict the expression patterns of unknown genes with remarkable accuracy, leading to the discovery of new organizer-related gastrula stage expression patterns for 19 genes. Moreover, the patterns of gene response observed within these clusters allow us to parse apart the contributions of BMP and Wnt inhibition in organizer function. We find that the majority of gastrula patterning genes respond transcriptionally to these activities according to only a few stereotyped patterns, allowing us to describe suites of genes that are likely to share similar regulatory mechanisms. These suites of genes demonstrate a mechanism where BMP inhibition initiates the organizer program before gastrulation, and Wnt inhibition maintains and drives the organizer program during gastrulation.
Genomic analysis of Xenopus organizer function.
Specimen part
View SamplesStrains devoid of ppGpp (relA spoT; called ppGpp0), and ppGpp0 dksA- exhibit several amino acid requirements for growth on minimal media. We found that overexpression of DksA can complement some of those requirements. Since DksA is a factor that binds to the RNA polymerase secondary channel, we wondered if other secondary channel proteins might also exert a similar role with respect to growth on minimal media. In our study we found that GreA and partially GreB can in fact complement these requirements under certain conditions. Here, we wished to investigate a broader effect of GreA and GreB on ppGpp0 and ppGpp0 dksA- strains. Since the parent strains are unable to grow in minimal media, we had to supplement the M9 glucose medium with a set of amino acids (DFHILQSTV). We found that both, GreA and GreB can affect a much larger set of genes in the absence of dksA, than in its presence. Also, GreA seems to affect more genes than GreB, under both conditions.
Effects on growth by changes of the balance between GreA, GreB, and DksA suggest mutual competition and functional redundancy in Escherichia coli.
No sample metadata fields
View SamplesWe used microarrays to provide a transcriptomic signature of different types of cholestasis evoked by 3 different drugs and obstructive surgery
Robustness testing and optimization of an adverse outcome pathway on cholestatic liver injury.
Specimen part, Cell line, Treatment
View Samples