The Hox complex consists of 39 genes arranged in 4 clusters of flanking genes and 13 paralogous groups in mammals. To assess the functional redundancy of Hox abdominal-B genes during renal development, we used a modified recombineering strategy to simultaneous introduce frameshift mutations into the Hox9, Hox10, and Hox11 flanking genes of the HoxA, HoxC, and HoxD paralogous groups. We performed RNA seq on whole kidneys at E18.5 in triplicates for representative genotypes including: wild type; Hoxa9,10,11-/- HoxC9,10,11+/-, Hoxa9,10,11+/- HoxC9,10,11-/-, Hoxa9,10,11-/- HoxC9,10,11-/-. Our results suggest that the loss of Hox function results in a partial metanephric to mesonephric transformation, with tubules co-expressing markers of both proximal tubules and collecting ducts, as well as markers of mesonephric-derived epididymis tubules. Overall design: mRNA profiles were generated by performing RNA-seq on whole kidneys at E18.5 in triplicates for Hox mutant genotypes including: 1) wild type; 2) Hoxa9,10,11-/- HoxC9,10,11+/-, 3) Hoxa9,10,11+/- HoxC9,10,11-/-, and 4) Hoxa9,10,11-/- HoxC9,10,11-/- by deep sequencing using Illumina Hi-Seq 2500
Disruption of Hox9,10,11 function results in cellular level lineage infidelity in the kidney.
Specimen part, Cell line, Subject
View SamplesThe aim of this study is to profile gene expression dynamics during the in vitro differentiation of embryonic stem cells into ventral motor neurons. Expression levels were profiled using Affymetrix microarrays at six timepoints during in vitro differentiation: ES cells (Day 0), embryoid bodies (Day 2), retinoid induction of neurogenesis (Day 2 +8hours of exposure to retinoic acid), neural precursors (Day 3), progenitor motor neurons (Day 4), postmitotic motor neurons (Day 7).
Ligand-dependent dynamics of retinoic acid receptor binding during early neurogenesis.
Cell line
View SamplesTranscriptional programming of cell identity promises to open up new frontiers in regenerative medicine by enabling the efficient production of clinically relevant cell types. We examine if such cellular programming is accomplished by transcription factors that each have an independent and additive effect on cellular identity, or if programming factors synergize to produce an effect that is not independently obtainable. The combinations of Ngn2-Isl1-Lhx3 and Ngn2-Isl1-Phox2a transcription factors program embryonic stem cells to express a spinal or cranial motor neuron identity respectively. The two alternate expression programs are determined by recruitment of Isl1/Lhx3 and Isl1/Phox2a pairs to distinct genomic locations characterized by two alternative dimeric homeobox motifs. These results suggest that the function of programming modules relies on synergistic interactions among transcription factors and thus cannot be extrapolated from the study of individual transcription factors in a different cellular context.
Synergistic binding of transcription factors to cell-specific enhancers programs motor neuron identity.
Cell line, Treatment
View SamplesMulticiliated cells are crucial for fluid and ion transport in epithelia of a variety of organs and their impaired development and function are seen in human diseases affecting the brain, respiratory, and reproductive tracts. Multiciliogenesis requires activation of a specialized transcription program coupled to complex cytoplasmic events that lead to large-scale centriole amplification to generate multicilia. Yet, it remains unclear how these events are coordinated to initiate multiciliogenesis in epithelial progenitors. Here we identify an unsuspected mechanism orchestrated by the transcription factor E2f4 essential to integrate these processes. We show that after inducing a transcriptional program of centriole biogenesis, E2f4 translocates to the cytoplasm to become a core component of structures classically identified as fibrous granules (FG), acting as organizing centers for deuterosome assembly and centriole amplification. Remarkably, loss of cytoplasmic E2f4 prevents FG aggregation, deuterosome assembly and multicilia formation even when E2f4s transcriptional function is preserved. Moreover, in E2f4-deficient cells multiciliogenesis is rescued only if both nuclear and cytoplasmic E2f4 activities are restored. Thus, E2f4 integrates previously unrelated nuclear and cytoplasmic events of the multiciliated cell program.
Cytoplasmic E2f4 forms organizing centres for initiation of centriole amplification during multiciliogenesis.
Specimen part
View SamplesBasic helix-loop-helix (bHLH) proneural transcription factors (TFs) Ascl1 and Neurog2 are integral to the development of the nervous system. Here, we investigated the molecular mechanisms by which Ascl1 and Neurog2 control the acquisition of generic neuronal fate and impose neuronal subtype identity. Using direct neuronal programming of embryonic stem cells, we found that Ascl1 and Neurog2 regulate distinct targets by binding to largely different sets of sites. Their divergent binding pattern is not determined by the previous chromatin state but distinguished by specific E-box enrichments which reflect the DNA sequence preference of the bHLH domain. The divergent Ascl1 and Neurog2 binding patterns result in distinct chromatin accessibility and enhancer activity landscapes that shape the binding and activity of downstream TFs during neuronal specification. Our findings suggest that proneural factors contribute to neuronal diversity by differentially altering the chromatin landscapes that shape the binding of neuronally expressed TFs. Overall design: Single-cell RNA-seq was used to characterize gene expression in mixed populations of mES cells containing induced expression of either Ascl1 or Neurog2.
Proneural factors Ascl1 and Neurog2 contribute to neuronal subtype identities by establishing distinct chromatin landscapes.
Specimen part, Treatment, Subject
View SamplesEmergence of antiestrogen-resistant cells in MCF-7 cells during suppression of estrogen signaling is a widely accepted model of acquired breast cancer resistance to endocrine therapy. To obtain insight into the genomic basis of endocrine therapy resistance, we characterized MCF-7 monoclonal sublines that survived 21-day exposure to tamoxifen (T-series sublines) or fulvestrant (F-series sublines) and sublines unselected by drugs (U-series). All T/F-sublines were resistant to the cytocidal effects of both tamoxifen and fulvestrant. However, their responses to the cytostatic effects of fulvestrant varied greatly, and their remarkably diversified morphology showed no correlation with drug resistance. mRNA expression profiles of the U-sublines differed significantly from those of the T/F-sublines, whose transcriptomal responsiveness to fulvestrant was largely lost. A set of genes strongly expressed in the U-sublines successfully predicted metastasis-free survival of breast cancer patients. Most T/F-sublines shared highly homogeneous genomic DNA aberration patterns that were distinct from those of the U-sublines. Genomic DNA of the U-sublines harbored many aberrations that were not found in the T/F-sublines. These results suggest that the T/F-sublines are derived from a common monoclonal progenitor that lost transcriptomal responsiveness to antiestrogens as a consequence of genetic abnormalities many population doublings ago, not from the antiestrogen-sensitive cells in the same culture during the exposure to antiestrogens. Thus, the apparent acquisition of antiestrogen resistance by MCF-7 cells reflects selection of preexisting drug-resistant subpopulations without involving changes in individual cells. Our results suggest the importance of clonal selection in endocrine therapy resistance of breast cancer.
Antiestrogen-resistant subclones of MCF-7 human breast cancer cells are derived from a common monoclonal drug-resistant progenitor.
Specimen part, Cell line, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Saltatory remodeling of Hox chromatin in response to rostrocaudal patterning signals.
Specimen part, Cell line, Time
View SamplesWe aim to understand the role that Cdx2 plays in specifying the rostro-caudal identity of differentiating motor neurons. We find that expressing Cdx2 in combination with FGF signaling is sufficient to produce motor neurons with a more caudal identity. ChIP-seq analysis of Cdx2 finds that it binds extensively throughout the Hox regions in progenitor motor neurons. Analysis of polycomb-associated chromatin over Hox regions in the subsequently generated motor neurons finds that Cdx2 binding corresponds to chromatin domains encompassing de-repressed caudal Hox genes. These results suggest a direct role for Cdx2 in specifying caudal motor neuron identity.
Saltatory remodeling of Hox chromatin in response to rostrocaudal patterning signals.
Specimen part, Cell line, Time
View SamplesSuz12(Bgal/Bgal) ESCs express a truncated form of Suz12 fused to Beta-galactosidase. These cells maintain a reduced level of H3K27me3 despite this mutation to a core component of PRC2, unlike Eed-/- ESCs whose H3K27me3 is ablated. Overall design: RNA-seq was performed in wild type and Suz12(Bgal/Bgal) ESCs, here used to demonstrate the coverage of the Suz12 gene in mRNA reads.
Saltatory remodeling of Hox chromatin in response to rostrocaudal patterning signals.
Specimen part, Cell line, Subject
View SamplesDirect programming via the overexpression of transcription factors (TFs) aims to control cell fate at a precision that will be instrumental for clinical applications. However, direct programming of terminal fates remains an obscure process. Taking advantage of the rapid and uniquely efficient programming of spinal motor neurons by overexpression of Ngn2, Isl1 and Lhx3, we have characterized gene expression, chromatin and transcription factor binding time-course dynamics during complete motor neuron programming. Our studies point to a surprisingly dynamic programming process. Promoter chromatin and expression analysis reveals at least three distinct phases of gene activation, while programming factor binding shifts from one set of targets to another, controlling regulatory region activity and gene expression. Furthermore, our evidence suggest that the enhancers and genes activated in the final stage of motor neuron processing are dependent on the combined activities of Isl1 and Lhx3 factors with Ebf and Onecut TFs that are themselves activated midway through the programming process. Our results suggest an unexpected multi-stage model of motor neuron programming in which the programming TFs require activation of a set of intermediate regulators before they complete the programming process. Overall design: Gene expression was characterized by single-cell RNA-seq during the direct programming of ES cells into motor neurons using over-expression of Ngn2-Isl1-Lhx3 programming factors.
A Multi-step Transcriptional and Chromatin State Cascade Underlies Motor Neuron Programming from Embryonic Stem Cells.
Specimen part, Cell line, Treatment, Subject
View Samples