Context dependent molecular cues shape the formation of the cerebral vascular network and the function of the blood-brain barrier (BBB). The Wnt/ß-catenin pathway is orchestrating CNS vascular development, but downstream mediators have not been characterized. Here we generated an endothelial cell-specific R26-Axin1 overexpression (AOE) mouse model to inhibit Wnt/ß-catenin signaling. In AOE mice we discovered that blockade of Wnt/ß-catenin pathway leads to premature regression and remodeling without compromising BBB integrity. Importantly, by comparing transcriptomes of endothelial cells from wildtype and AOE mice, we identified ADAMTSL2 as a novel Wnt/ß-catenin-induced, secreted factor, important for stabilizing the BBB during development. Zebrafish loss-of-function and gain-of-function models, further demonstrated that ADAMTSL2 is crucial for normal vascular development and could rescue vascular phenotypes in AOE zebrafish brains. In conclusion, the studies presented here reveal a hitherto unrecognized role of ADAMTSL2 as an endothelial cell-specific mediator of Wnt/ß-catenin signaling during CNS vascular development and BBB-formation. Overall design: Examination of expression changes in mouse brain endothelial cells when overexpressing Axin1
Disruption of the Extracellular Matrix Progressively Impairs Central Nervous System Vascular Maturation Downstream of β-Catenin Signaling.
No sample metadata fields
View SamplesPurpose:
Sequential gene expression profiling during treatment for identification of predictive markers and novel therapeutic targets in chronic lymphocytic leukemia.
Treatment
View SamplesAcute liver injury is a critical life-threatening event. Common causes are infections, intoxication, and ischemic conditions. The cytokine Interleukin 22 (IL-22) has been implicated in this process. However, the role of IL-22 during acute liver damage is controversial, since both protective and pathogenic properties have been reported. IL-22 binding protein (IL-22BP, IL-22Ra2), a soluble endogenous inhibitor of IL-22, is able to regulate IL-22 activity, and thus might explain some of the controversial findings. Since the role of IL-22BP in liver injury is unknown, we used Il22bp deficient mice and mouse models for acute liver damage to address this point. We found that Il22bp deficient mice were more susceptible to ischemia- and acetaminophen- induced liver damage. Deficiency of Il22bp caused increased hepatic damage and delayed liver regeneration. Using an unbiased approach, we found that IL-22, if uncontrolled in Il22bp deficient mice, induced Cxcl10 expression by hepatocytes, thereby recruiting inflammatory CD11b+Ly6C+ monocytes into the liver upon liver damage. Accordingly, neutralization of Cxcl10 reversed the increased disease susceptibility of Il22bp deficient mice. In conclusion, our data suggest dual functions of IL-22 in acute liver damage, and highlight the need to control IL-22 activity via IL-22BP. Overall design: RNA sequencing of RNA isolated from liver tissue from mice that underwent liver reperfusion treatment (IR) or sham surgery, in triplicate for three genotypes (Wt, Il22-/- and Il22bp-/-).
A Protective Function of IL-22BP in Ischemia Reperfusion and Acetaminophen-Induced Liver Injury.
Specimen part, Treatment, Subject
View SamplesWe adopted the STRT-seq [Islam et al., Nat Methods 11, 163-166 (2013)] RNA-seq technology to a 9600-well array and applied it to analyze single cells from mouse and human cortex single cells. Overall design: 2192 single cells from mouse somatosensory cortex and 2028 single nuclei from human post-mortem middle temporal gyrus cortex.
STRT-seq-2i: dual-index 5' single cell and nucleus RNA-seq on an addressable microwell array.
No sample metadata fields
View SamplesHaploid budding yeast has two mating types, defined by the alleles of the MAT locus, MATa and MATa. Mating occurs when two haploid cells of opposite mating types signal to each other using reciprocal pheromones and receptors, polarize and grow towards each other, and eventually fuse to form a single diploid cell. The pheromones and receptors are necessary and sufficient to define a mating type, but other mating type-specific proteins make mating more efficient. We examined the role of these proteins by genetically engineering “transvestite” cells that swap the pheromone, pheromone receptor, and pheromone processing factors of one mating type for another. These cells can mate with each other, but their mating is inefficient. By characterizing their mating defects and examining their transcriptomes, we found Afb1 (a-factor barrier), a novel MATa-specific protein that interferes with a-factor, the pheromone secreted by MATa cells. We show that strong pheromone secretion is essential for efficient mating and that the weak mating of transvestites can be improved by boosting their pheromone production. Using synthetic biology, it is possible to characterize the factors that control efficiency in biological processes. In the case of budding yeast mating, selection for increased mating efficiency is likely to have continually boosted pheromone levels and the ability to discriminate between partners who make more (potentially fitter) and less (potentially less fit) pheromones. This sensitivity to which partner makes more pheromone comes at a cost: it means mating is not robust in situations where all potential partners make less pheromone. Overall design: 4 conditions were analysed, each with 3 biological replicates. The conditions were unstimulated MATa cells in YPD. Stimulated MATa cells in YPD+10nM a-factor. Unstimulated MATa cells in YPD. Stimulated MATa cells in YPD+10nM a-factor.
Genetically engineered transvestites reveal novel mating genes in budding yeast.
Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The histone chaperone CAF-1 safeguards somatic cell identity.
Specimen part, Time
View SamplesCellular differentiation involves profound changes in the chromatic landscape, yet the mechanisms by which somatic cell identity is subsequently maintained remain incompletely understood. To further elucidate regulatory pathways that safeguard the somatic state, we performed two comprehensive RNAi screens targeting chromatin factors during transcription factor-mediated reprogramming of mouse fibroblasts to induced pluripotent stem cells (iPSCs). Remarkably, subunits of the chromatin assembly factor-1 (CAF-1) complex emerged as the most prominent hits from both screens, followed by modulators of lysine sumoylation and heterochromatin maintenance. Suppression of CAF-1 increased reprogramming efficiency by several orders of magnitude and facilitated iPSC formation in as little as 4 days. Mechanistically, CAF-1 suppression led to a more accessible chromatin structure at enhancer elements early during reprogramming. These changes were accompanied by a decrease in somatic heterochromatin domains, increased binding of Sox2 to pluripotency-specific targets and activation of associated genes. Notably, suppression of CAF-1 also enhanced the direct conversion of B cells into macrophages and fibroblasts into neurons. Together, our findings reveal the histone chaperone CAF-1 as a novel regulator of somatic cell identity during transcription factor-induced cell fate transitions and provide a potential strategy to modulate cellular plasticity in a regenerative setting.
The histone chaperone CAF-1 safeguards somatic cell identity.
Specimen part, Time
View SamplesThe sexually dimorphic expression of genes across 26 somatic rat tissues was using Affymetrix RAE-230 genechips. We considered probesets to be sexually dimorphically expressed (SDE) if they were measurably expressed above background in at least one sex, there was at least a two-fold difference in expression (dimorphism) between the sexes, and the differences were statistically significant after correcting for false discovery. 14.5% of expressed probesets were SDE in at least one tissue, with higher expression nearly twice as prevalent in males compared to females. Most were SDE in a single tissue. Surprisingly, nearly half of the probesets that were (SDE) in multiple tissues were oppositely sex biased in different tissues, and most SDE probesets were also expressed without sex bias in other tissues. Two genes were widely SDE: Xist (female-only) and Eif2s3y (male-only). The frequency of SDE probesets varied widely between tissues, and was highest in the duodenum (6.2%), whilst less than 0.05% in over half of the surveyed tissues. The occurrence of SDE probesets was not strongly correlated between tissues. Within individual tissues, however, relational networks of SDE genes were identified. In the liver, networks relating to differential metabolism between the sexes were seen. The estrogen receptor was implicated in differential gene expression in the duodenum. To conclude, sexually dimorphic gene expression is common, but highly tissue-dependent. Sexually dimorphic gene expression may provide insights into mechanisms underlying phenotypic sex differences.
The incidence of sexually dimorphic gene expression varies greatly between tissues in the rat.
Sex, Specimen part
View SamplesWe used microarrays to find Stat6 dependent genes in control and IL-4 exposed bone marrow derived macrophages.
Alternatively activated macrophages inhibit T-cell proliferation by Stat6-dependent expression of PD-L2.
Specimen part
View SamplesGene expression analysis of yw follicles at S9/10a, S10B, S12, and S14; Gene expression analysis of pxt mutant follicles (f01000 and EY03052) at S10B, S12, S14
Drosophila eggshell production: identification of new genes and coordination by Pxt.
Sex, Specimen part
View Samples