This experiment was conducted to identify target genes of the peroxisome proliferator-activated receptor beta (PPARb) in skeletal muscle of transgenic mice that overexpressed PPARb.
The nuclear receptor PPARβ/δ programs muscle glucose metabolism in cooperation with AMPK and MEF2.
Age, Specimen part
View SamplesDrosophila melanogaster neural stem cells (neuroblasts [NBs]) divide asymmetrically by differentially segregating protein determinants into their daughter cells. Although the machinery for asymmetric protein segregation is well understood, the events that reprogram one of the two daughter cells toward terminal differentiation are less clear. In this study, we use time-resolved transcriptional profiling to identify the earliest transcriptional differences between the daughter cells on their way toward distinct fates. By screening for coregulated protein complexes, we identify vacuolar-type H+–ATPase (v-ATPase) among the first and most significantly down-regulated complexes in differentiating daughter cells. We show that v-ATPase is essential for NB growth and persistent activity of the Notch signaling pathway. Our data suggest that v-ATPase and Notch form a regulatory loop that acts in multiple stem cell lineages both during nervous system development and in the adult gut. We provide a unique resource for investigating neural stem cell biology and demonstrate that cell fate changes can be induced by transcriptional regulation of basic, cell-essential pathways. Overall design: Comparison of transcriptomes of wild-type type I NBs and GMCs of different ages (1.5h, 3h or 5h old) isolated by FACS from Drosophila melanogaster larval brains.
Time-resolved transcriptomics in neural stem cells identifies a v-ATPase/Notch regulatory loop.
Specimen part, Subject
View SamplesThe TRIM-NHL protein Brain tumor (Brat) acts as a tumor suppressor in the Drosophila brain, but how it suppresses tumor formation is not completely understood. Here, we combine temperature controlled brat RNAi with transcriptome analysis to identify the immediate brat targets in Drosophila neuroblasts. Besides the known target Deadpan (Dpn), our experiments identify the transcription factor Zelda (Zld) as a critical target of brat. Our data show that Zld is expressed in neuroblasts and required to allow re-expression of Dpn in transit amplifying intermediate neural progenitors. Upon neuroblast division, Brat is enriched in one daughter cell where its NHL domain directly binds to specific motifs in the 3'UTR of dpn and zld mRNA to mediate their degradation. In brat mutants, both Dpn and Zld continue to be expressed, but inhibition of either transcription factor prevents tumorigenesis. Our genetic and biochemical data indicate that Dpn inhibition requires higher Brat levels than Zld inhibition and suggest a model where stepwise post-transcriptional inhibition of distinct factors ensures sequential generation of fates in a stem cell lineage. Overall design: Comparison of transcriptomes of Drosophila melanogaster control and brat RNAi larval brain type II neural stem cell lineages.
The tumor suppressor Brat controls neuronal stem cell lineages by inhibiting Deadpan and Zelda.
Specimen part, Subject
View SamplesIntroduction of brain tumor-relevant genetic aberrations initiates different subtypes of brain tumor-like neoplasms in cerebral organoids Overall design: Comparison of abundances (TPM) from different brain tumor organoid groups
Author Correction: Genetically engineered cerebral organoids model brain tumor formation.
Specimen part, Subject
View SamplesIntroduction of brain tumor-relevant genetic aberrations initiates different subtypes of brain tumor-like neoplasms in cerebral organoids Overall design: Comparison of transcriptomes from different brain tumor organoid groups
Author Correction: Genetically engineered cerebral organoids model brain tumor formation.
Specimen part, Subject
View SamplesEngineered brain organoids (enCORs) exhibit reproducible neural differentiation and forebrain regionalization. Overall design: Comparison of transcriptomes from bioengineered micropatterned enCORs and spheroids at 20 days and 60 days
Guided self-organization and cortical plate formation in human brain organoids.
Specimen part, Subject, Time
View SamplesSystemic sclerosis (SSc) is a devastating disease affecting the skin and internal organs. Dermal fibrosis manifests early and Modified Rodnan Skin Scores (MRSS) correlate with disease progression. Transcriptomics of SSc skin biopsies suggest the role of the in vivo microenvironment in maintaining the pathological myofibroblasts. Therefore, defining the structural changes in dermal collagen in SSc patients could inform our understanding of fibrosis pathogenesis. Here, we report a method for quantitative whole-slide image analysis of dermal collagen from SSc patients, and our findings of more aligned dermal collagen bundles in diffuse cutaneous SSc (dcSSc) patients. Using the bleomycin-induced mouse model of SSc, we identified a distinct high dermal collagen bundle alignment gene signature, characterized by a concerted upregulation in cell migration, adhesion, and guidance pathways, and downregulation of spindle, replication, and cytokinesis pathways. Furthermore, increased bundle alignment induced a cell migration gene signature in fibroblasts in vitro, and these cells demonstrated increased directed migration on aligned ECM fibers that is dependent on expression of Arhgdib (Rho GDP-dissociation inhibitor 2). Our results indicate that increased cell migration is a cellular response to the increased collagen bundle alignment featured in fibrotic skin. Moreover, many of the cell migration genes identified in our study are shared with human SSc skin and may be new targets for therapeutic intervention. Overall design: For bleomycin experiments, 8 week old C57Bl/6 female mice were used.The bleomycin model was established with daily subcutaneous injections of bleomycin (100uL at 1U/mL) into the back skin. Experimental timepoints include: saline, 2 weeks bleo, 4 weeks bleo, 6 weeks recovery, and 10 weeks recovery.
Increased dermal collagen bundle alignment in systemic sclerosis is associated with a cell migration signature and role of Arhgdib in directed fibroblast migration on aligned ECMs.
No sample metadata fields
View SamplesTo obtain a genomic view of hepatocyte nuclear factor-4 (HNF-4) in the regulation of the inflammatory response, microarray analysis was used to probe the expression profile of an inflammatory response induced by cytokines in a model of knock-down HNF-4 HepG2 cells. The results indicate an extensive role for HNF-4 plays in the regulation of a large number of the liver-specific genes. Majority of genes (71%) affected by cytokine treatment are also affected by HNF-4 knock-down. This significant overlap suggests that HNF-4 may play a role in regulating the cytokine-induced inflammatory response.
Expression profile analysis of the inflammatory response regulated by hepatocyte nuclear factor 4α.
No sample metadata fields
View SamplesPrimary murine fetal liver cells were freshly isolated from day e14.5 livers and then sorted for successive differentiation stages by Ter119 and CD71 surface expression (ranging from double-negative CFU-Es to Ter-119 positive enucleated erythrocytes) [Zhang, et al. Blood. 2003 Dec 1; 102(12):3938-46]. RNA isolated from each freshly isolated, stage-sorted population was reverse-transcribed, labelled, and then hybridized onto 3' oligo Affymetrix arrays. Important erythroid specific genes as well as the proteins that regulate them were elucidated through this profiling based on coexpression and differential expression patterns as well as by extracting specific GO categories of genes (such as DNA-binding proteins).
Homeodomain-interacting protein kinase 2 plays an important role in normal terminal erythroid differentiation.
Specimen part
View SamplesUridylation of diverse RNA species represents an emerging theme in post-transcriptional gene regulation. In the microRNA pathway, such modifications regulate small RNA biogenesis and stability in plants, worms and mammals. Here, we report the first uridylyltransferase that acts on small RNAs in Drosophila, which we refer to as Tailor. Tailor is the source for the majority of 3´ end-modifications in microRNAs and predominantly targets precursor-hairpins. Uridylation modulates the characteristic two-nucleotide 3´ overhangs of microRNA hairpins, which regulates processing by Dicer-1 and destabilizes RNA hairpins. Furthermore, Tailor preferentially uridylates mirtron-hairpins, thereby impeding the production of non-canonical microRNAs. Mirtron-selectivity is explained by unique primary sequence specificity of Tailor, selecting RNA substrates ending with a 3´ guanosine, a feature not previously observed for TUTases. In contrast to mirtrons, conserved Drosophila pre-miRNAs are significantly depleted in 3´ guanosine, thereby escaping regulatory uridylation. Our data support the hypothesis that evolutionary adaptation to pre-miRNA uridylation shapes the nucleotide composition of pre-miRNA 3´ ends. Hence, hairpin-uridylation may serve as a barrier for the de novo creation of miRNAs in Drosophila. Overall design: mRNA sequencing of Drosophila S2 cells (3-times; control libraries) and three biological replicates of S2 cells stably depleted of CG1091/Tailor by CRISPR/Cas9
Uridylation of RNA Hairpins by Tailor Confines the Emergence of MicroRNAs in Drosophila.
Cell line, Subject
View Samples