The Snf1 kinase plays a critical role in recalibrating cellular metabolism in response to glucose depletion. Hundreds of genes show changes in expression levels when the SNF1 gene is deleted. However, cells can adapt to the absence of a specific gene when grown in long term culture. Here we apply a chemical genetic method to rapidly and selectively inactivate a modified Snf1 kinase using a pyrazolopyrimidine inhibitor. By allowing cells to adjust to a change in carbon source prior to inhibition of the Snf1 kinase activity, we identified a set of genes whose expression increased when Snf1 was inhibited. Prominent in this set are genes that are activated by Gcn4, a transcriptional activator of amino acid biosynthetic genes. Deletion of Snf1 increased Gcn4 protein levels without affecting its mRNA levels. The increased Gcn4 protein levels required the Gcn2 kinase and Gcn20, regulators of GCN4 translation. These data indicate that Snf1 functions upstream of Gcn20 to regulate control of GCN4 translation.
A chemical genomics study identifies Snf1 as a repressor of GCN4 translation.
No sample metadata fields
View SamplesMatching sets of RfxCasR and shRNAs targeting ANXA4 and B4GALNT1 plus non-targeting (NT) controls were profiled by mRNA sequencing to compare non-specific transcriptome perturbations for both shRNA and RfxCasR technologies. Overall design: Three biological replicates for 3 shRNAs and 2 RfxCasR guide RNAs plus 2 RfxCasR arrays expresssed in HEK 293FT cells
Transcriptome Engineering with RNA-Targeting Type VI-D CRISPR Effectors.
Cell line, Treatment, Subject
View SamplesThe transcriptomes of individual small and large B cells after 24 h of stimulation were sequenced and genes upregulated in small or large cells were found and analyzed to provide a global charactarization of transcription patterns in growing B cells. Overall design: We identified 5 large and 5 small viable B cells from images of the C1 IFC containing captured cells. We prepared libraries for the 10 individual cells, a positive bulk control (containing diluted bulk cDNA), a negative control containing only the ERCC spikeins, and a 0h bulk control.
A multi-scale approach reveals that NF-κB cRel enforces a B-cell decision to divide.
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View SamplesFaithful execution of developmental programs relies on the acquisition of unique cell identities from pluripotent progenitors, a process governed by combinatorial inputs from numerous signaling cascades that ultimately dictate lineage-specific transcriptional outputs. Despite growing evidence that metabolism is integrated with many molecular networks, how pathways that control energy homeostasis may affect cell fate decisions is largely unknown. Here, we show that AMPK, a central metabolic regulator, plays critical roles in lineage specification. Although AMPK-deficient embryonic stem cells (ESCs) were normal in the pluripotent state, these cells displayed profound defects upon differentiation, failing to generate chimeric embryos and preferentially adopting an ectodermal fate at the expense of the endoderm during embryoid body (EB) formation. AMPK-/- EBs exhibited reduced levels of Tfeb, a master transcriptional regulator of lysosomes, leading to diminished endolysosomal function. Remarkably, genetic loss of Tfeb also yielded endodermal defects, while AMPK-null ESCs over-expressing this transcription factor normalized their differential potential, revealing an intimate connection between Tfeb/lysosomes and germ layer specification. The compromised endolysosomal system resulting from AMPK or Tfeb inactivation blunted Wnt signaling, while up-regulating this pathway restored expression of endodermal markers. Collectively, these results uncover the AMPK pathway as a novel regulator of cell fate determination during differentiation. Overall design: 2 WT and 2 AMPK DKO ESC lines were differentiated into embryoid bodies (EBs) for various lengths of time (2, 4, 8, and 12 days) in high and low glucose conditions. Both ESC and EB samples were profiled by mRNA-seq to examine how global gene expression changes associated with ESC differentiation are affected by AMPK deletion.
AMPK governs lineage specification through Tfeb-dependent regulation of lysosomes.
Specimen part, Subject
View SamplesAging is associated with mitochondrial dysfunction and insulin resistance. We conducted a study to determine the role of long-term vigorous endurance exercise on age-related changes in insulin sensitivity and various indices of mitochondrial functions.
Endurance exercise as a countermeasure for aging.
No sample metadata fields
View SamplesTbx20 is a transcription factor important for heart development. To assess the role of Tbx20 in the adult heart, we generated a conditional knockout for this gene, specifically in cardiomyocytes. We profiled gene expression levels using RNA-seq in both normal and knockout adult mouse hearts to identify genes and pathways regulated by Tbx20. The article describing the Tbx20 knockout mouse is under review, a reference will be added when published. Overall design: Analysis of triplicate mRNA samples of adult mouse, comparing normal and knockout
Dual transcriptional activator and repressor roles of TBX20 regulate adult cardiac structure and function.
Age, Specimen part, Cell line, Subject
View SamplesHomeodomain (HD) proteins comprise a large family of evolutionarily conserved transcription factors (TFs) having diverse developmental functions, yet they paradoxically recognize very similar DNA sequences. To investigate how HDs control cell-specific gene expression patterns, we determined the DNA binding specificities of a broad range of HDs critical for Drosophila embryonic mesoderm development. These studies revealed particular sequences that are bound by one HD and not by others. Such HD-preferred binding sites are overrepresented in the noncoding regions of genes that are regulated by the corresponding HD. Moreover, we show at single-cell resolution in intact embryos that the HD Slouch (Slou) controls myoblast gene expression through unique DNA sequences that are preferentially bound by Slou. These findings demonstrate that the sequence of a HD-binding site dictates which HD family member binds to and regulates a particular enhancer. This represents a novel mechanism for how cell type-specific TFs induce the distinct genetic programs of individual embryonic cells.
Molecular mechanism underlying the regulatory specificity of a Drosophila homeodomain protein that specifies myoblast identity.
Specimen part
View SamplesWe compared polyIC stimulated cells in the presence of either GFP or NS5 protein Overall design: A549 cells presence with GFP- or NS5-expressing plasmid using Polyjet (Signagen) according to manufacturer instructions, and 30 hours later stimulated with polyIC (Tocris) as previously described (Marazzi et al., 2012). At 12 hours post-stimulation, total cellular RNA was purified by RNeasy column (Qiagen).
Comparative Flavivirus-Host Protein Interaction Mapping Reveals Mechanisms of Dengue and Zika Virus Pathogenesis.
Specimen part, Cell line, Subject
View SamplesIdentifying the functions of proteins, which define specific subnuclear structures and territories, is important for understanding eukaryotic nuclear dynamics. Sp100 is a prototypical protein of ND10/PML bodies and co-localizes with the proto-oncogenic protein PML and Daxx, proteins with critical roles in oncogenic transformation, interferon-mediated viral resistance and response to PML-directed cancer therapeutics. Sp100 isoforms contain PHD, Bromo and HMG domains and are highly sumoylated at ND10/PML bodies, all characteristics suggestive of a role in chromatin mediated gene regulation. However, no clear role for the Sp100 component of PML bodies in oncogenesis has been defined. Using isoform-specific knockdown techniques, we show that most human diploid fibroblasts, which lack Sp100, rapidly senesce and discuss gene expression changes associated with this rapid senescence.
Sp100 as a potent tumor suppressor: accelerated senescence and rapid malignant transformation of human fibroblasts through modulation of an embryonic stem cell program.
Cell line, Treatment
View SamplesGene expression patterns in the brain are strongly influenced by the severity of physiological stress at death. This agonal effect, if not well controlled, can lead to spurious findings in case-control comparisons. While many recent studies match samples by tissue pH and clinically recorded agonal conditions, we found that these commonly used indicators were sometimes at odds with observed stress-related patterns of gene expression, and that matching by these criteria still sometimes results in identifying differences between cases and controls that are primarily driven by residual agonal effects. This problem is analogous to the one in genetic studies, where race and ethnicity are often imprecise proxies for complex environmental and genetic factors.
Sample matching by inferred agonal stress in gene expression analyses of the brain.
Subject
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