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GSE35038
Mus musculus
29 Downloadable Samples
Affymetrix Mouse Genome 430A 2.0 Array (mouse430a2)
Description
Activation of the MLL-ENL-ERtm oncogene initiates aberrant proliferation of myeloid progenitors. Here, we show induction of a fail-safe mechanism mediated by the DNA damage response (DDR) machinery that results in activation of the ATR/ATM-Chk1/Chk2-p53/p21 checkpoint and cellular senescence at early stages of cellular transformation caused by a regulatable MLL-ENL-ERtm in mice. Furthermore, we identified the transcription program underlying this intrinsic anti-cancer barrier, and DDR-induced inflammatory regulators that fine-tune the signaling towards senescence, thereby modulating the fate of MLL-ENL-immortalized cells in a tissue-environment-dependent manner. Our results indicate that DDR is a rate-limiting event for acquisition of stem cell-like properties in MLL-ENL-ERtm-mediated transformation, as experimental inhibition of the barrier accelerated the transition to immature cell states and acute leukemia development.
Publication Title
DNA damage response and inflammatory signaling limit the MLL-ENL-induced leukemogenesis in vivo.
Sample Metadata Fields
Specimen part, Disease stage
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
Distinctions between craniofacial and axial muscles exist from the onset of development and throughout adulthood. The masticatory muscles are a specialized group of craniofacial muscles that retain embryonic fiber properties throughout adulthood, suggesting that the developmental origin of these muscles may govern a pattern of expression that differs from limb muscles. To determine the extent of these differences, expression profiling of total RNA isolated from the masseter and tibialis anterior (TA) muscles of adult female mice was performed, which identified transcriptional changes in unanticipated functional classes of genes in addition to those associated with fiber type. In particular, the masseters displayed a reduction of transcripts associated with load-sensing and anabolic processes, and heightened expression of genes associated with stress. Consistent with these observations were a significantly smaller fiber cross-sectional area in masseters, significantly elevated load-sensing signaling (phosphorylated Focal Adhesion Kinase (FAK)), and increased apoptotic index in masseters compared to TA muscles. Based on these results, we hypothesize that masticatory muscles may sense and respond to load differently than limb muscles, where the drive for anabolic processes is reduced, and cell stress mediated processes are enhanced. These results establish a novel classification for the masseter muscle in the spectrum of skeletal muscle allotypes, and may provide insight into the molecular basis for specific muscle-related pathologies associated with masticatory muscles.
Publication Title
Expression profiling reveals heightened apoptosis and supports fiber size economy in the murine muscles of mastication.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Expression 430A Array (moe430a)
Description
Masseter and Tibialis anterior muscles from adult female control mice to determine expression differences between muscle groups
Publication Title
Expression profiling reveals heightened apoptosis and supports fiber size economy in the murine muscles of mastication.
Sample Metadata Fields
Sex, Age, Specimen part
View Samples- Pseudomonas aeruginosa
- 11 Downloadable Samples
- Affymetrix Pseudomonas aeruginosa Array (paeg1a)
Description
In Pseudomonas aeruginosa, partitioning protein ParB facilitates segregation of newly replicated chromosomes but is not essential for cell survival. Unlike in other bacteria, inactivation of parB leads to major changes of the transcriptome, suggesting that, directly or indirectly, ParB plays a role in regulation of gene expression in this organism.
Publication Title
Increased ParB level affects expression of stress response, adaptation and virulence operons and potentiates repression of promoters adjacent to the high affinity binding sites parS3 and parS4 in Pseudomonas aeruginosa.
Sample Metadata Fields
No sample metadata fields
View Samples- Arabidopsis thaliana
- 4 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
The establishment of ad/abaxial polarity is a fundamental event in plant development. It is critical for correct polar development of the leaf (the upper portion of the leaf is chloroplast rich and optimized for light capture while the lower portion is optimized for gas exchange) and for creating an environment that allows the formation of new meristems (centers of stem cell growth). Class III homeodomain-leucine zipper (HD-ZIPIII) proteins are conserved plant proteins that act as potent regulators of ad/abaxial polarity. HD-ZIPIII protein activity promotes the development of upper (adaxial) leaf fates and meristem formation; in its absence lower (abaxial) leaf fates develop and meristems fail to form. A network of regulatory factors controls the establishment of ad/abaxial leaf fates. However, this network is incomplete and how these factors control one another is poorly understood. Here we report a new family of plant genes, the LITTLE ZIPPER (ZPR) genes (consisting principally of a stretch of leucine zipper similar to the leucine zipper in HD-ZIPIII proteins) that are transcriptionally up-regulated by HD-ZIPIII activity. Furthermore, we show that the ZPR proteins interact with and repress HD-ZIPIII activity, thus forming a negative feedback loop. Our results suggest that HD-ZIPIII proteins exist in active homodimers and, together with the ZPR proteins, in inactive heterodimers. The newly discovered HD-ZIPIII/ZPR regulatory module would not only serve to dampen the effect of fluctuations in HD-ZIPIII protein levels but more importantly would provide a point of regulation - control over the ratio of inactive heterodimers to active homodimers - that could be influenced by other components of the pathway. For instance, the binding of a small hydrophobic molecule to the conserved (yet little understood) START domain present in the HD-ZIPIII proteins may influence the type of dimer formed.
Publication Title
A feedback regulatory module formed by LITTLE ZIPPER and HD-ZIPIII genes.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 5 Downloadable Samples
Illumina Genome Analyzer II, Affymetrix Human Gene 2.0 ST Array (hugene20st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
TET1 is a maintenance DNA demethylase that prevents methylation spreading in differentiated cells.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 9 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Tumor suppressor p53 promotes differentiation of human embryonic stem cells (hESCs), but an in-depth understanding of mechanism is lacking. Here, we define p53 functions in hESCs by genome wide profiling of p53 chromatin interactions and intersection with gene expression during early differentiation and in response to DNA damage. During differentiation, p53 targets and regulates a unique collection of genes, many of which encode transcription factors and developmental regulators with chromatin structure poised by OCT4 and NANOG and marked by repressive H3K27me3 in pluripotent hESCs. In contrast, genes associated with cell migration and motility are bound by p53 specifically after DNA damage. Surveillance functions of p53 in regulation of cell death and cell cycle genes are conserved during both DNA damage and differentiation. Our findings expand the registry of p53 -regulated genes in hESCs and define specific functions of p53 in opposing pluripotency, which are highly distinct from stress-induced p53 response in stem cells.
Publication Title
Genome-wide profiling reveals stimulus-specific functions of p53 during differentiation and DNA damage of human embryonic stem cells.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Drosophila melanogaster
- 8 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
LEM Domain proteins are key components of the nuclear lamina. Mutations in LEM-D proteins cause dystrophic diseases associated with compromised adult stem cells, yet it remains unclear how LEM-D proteins support stem cell function. Studies described here use the homologue of the LEM-D protein emerin in Drosophila, Otefin (Ote) as a model to understand LEM-D protein function in adult stem cells. Loss of Ote causes female sterility due to a complex germline stem cell (GSC) phenotype that includes both an early block in germline differentiation followed by GSC death. In vivo cell cycle analysis revealed that ote mutant GSCs display a lengthened S phase.We find that loss of the DNA Damage Response (DDR) Chk2 is able to not only rescue the lengthened S phase, but also GSC death and the block in germline differentiation. Activation of detrimental checkpoint in absence of Ote is conserved in both male and female GSCs and surprisingly occurs independent of detectable canonical DDR triggers, including transposon de-repression and DNA damage. Two defects were found to occur upstream of Chk2 activation: nuclear lamina morphological defects and altered heterochromatin organization. Together, our data identify the primary cause for a compromised adult stem cell population in the absence of a LEM-D protein.
Publication Title
Nuclear lamina dysfunction triggers a germline stem cell checkpoint.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 5 Downloadable Samples
Affymetrix Human Gene 2.0 ST Array (hugene20st), Illumina Genome Analyzer II
Description
We report that full length TET1 (TET1-FL) overexpression fails to induce global DNA demethylation in HEK293T cells. The preferential binding of TET1-FL to hypomethylated CpG islands (CGIs) through its CXXC domain leads to its inhibited 5-hydroxymethylcytosine (5hmC) production as methylation level increases. TET1-FL-induced 5hmC accumulates at CGI edges, while TET1 knockdown induces methylation spreading from methylated edges into hypomethylated CGIs. However, TET1 can regulate gene transcription independent of its dioxygenase catalytic function. Thus, our results identify TET1 as a maintenance DNA demethylase that does not purposely decrease methylation levels, but specifically maintains the DNA hypomethylation state of CGIs in adult cells.
Publication Title
TET1 is a maintenance DNA demethylase that prevents methylation spreading in differentiated cells.
Sample Metadata Fields
Cell line
View Samples- Homo sapiens
- 8 Downloadable Samples
- Illumina HiSeq 2500
Description
Understanding the physiological relevance of structures in mammalian mRNAs remains elusive, especially considering the global unfolding of mRNA structures in eukaryotic organisms recently examined, as well as the decade-long observation that mRNAs generally seem no more likely than random sequences to be stably folded. Here we show that RNA secondary structures, mostly weak and close-to-random, facilitate the 3'-end processing of thousands of human mRNAs by juxtaposing poly(A) signals (PASs) and cleavage sites that are otherwise too far apart. Folding of these 3'-end structures also enhances mRNA stability. Global structure probing shows that 3'-end regions are indeed folded in cells despite substantial unfolding of PAS-upstream regions. Analyses of thousands of ectopically expressed variants prove that folding both enhances processing and increases stability. Mutagenesis of a genomic locus further implicates structure-controlled processing in regulating neighboring gene expression. These results reveal widespread roles for RNA structure in mammalian mRNA biogenesis and metabolism. Overall design: This series includes 8 samples designed to measure the efficiency of 3'' end processing from a reporter library expressed in HEK293T cells and HeLa cells, in steady state or in nascent RNAs (by 4sU labeling and capture).
Publication Title
Widespread Influence of 3'-End Structures on Mammalian mRNA Processing and Stability.
Sample Metadata Fields
Cell line, Subject
View Samples