Filters
Technology
Platform
GSE65439
Drosophila melanogaster
9 Downloadable Samples
Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Cardiogenesis involves multiple biological processes acting in concert during development, a coordination achieved by the regulation of diverse cardiac genes by a finite set of transcription factors (TFs). Previous work from our laboratory identified the roles of two Forkhead TFs, Checkpoint suppressor homologue (CHES-1-like) and Jumeau (Jumu) in governing cardiac progenitor cell divisions by regulating Polo kinase activity. These TFs were also implicated in the regulation of numerous other cardiac genes. Here we show that these two Forkhead TFs play an additional and mutually redundant role in specifying the cardiac mesoderm (CM): eliminating the functions of both CHES-1-like and jumu in the same embryo results in defective hearts with missing hemisegments. Our observations indicate that this process is mediated by the Forkhead TFs regulating the fibroblast growth factor receptor Heartless (Htl) and the Wnt receptor Frizzled (Fz), both previously known to function in cardiac progenitor specification: CHES-1-like and jumu exhibit synergistic genetic interactions with htl and fz in CM specification, thereby implying function through the same genetic pathways, and transcriptionally activate the expression of both receptor-encoding genes. Furthermore, ectopic overexpression of either htl or fz in the mesoderm partially rescues the defective CM specification phenotype seen in embryos doubly homozygous for mutations in jumu and CHES-1-like. Together, these data emphasize the functional redundancy that leads to robustness in the cardiac progenitor specification process mediated by Forkhead TFs regulating the expression of signaling pathway receptors, and illustrate the pleiotropic functions of this class of TFs in different aspects of cardiogenesis.
Publication Title
Two forkhead transcription factors regulate the division of cardiac progenitor cells by a Polo-dependent pathway.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 5 Downloadable Samples
- Affymetrix Drosophila Genome Array (drosgenome1)
Description
The development of a complex organ requires the specification of appropriate numbers of each of its constituent cell types, as well as their proper differentiation and correct positioning relative to each other. During Drosophila cardiogenesis, all three of these processes are controlled by jumeau (jumu) and Checkpoint suppressor homologue (CHES-1-like), two genes encoding forkhead transcription factors that we discovered utilizing an integrated genetic, genomic and computational strategy for identifying novel genes expressed in the developing Drosophila heart. Both jumu and CHES-1-like are required during asymmetric cell division for the derivation of two distinct cardiac cell types from their mutual precursor, and in symmetric cell divisions that produce yet a third type of heart cell. jumu and CHES-1-like control the division of cardiac progenitors by regulating the activity of Polo, a kinase involved in multiple steps of mitosis. This pathway demonstrates how transcription factors integrate diverse developmental processes during organogenesis.
Publication Title
Two forkhead transcription factors regulate the division of cardiac progenitor cells by a Polo-dependent pathway.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 6 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
The development of a complex organ requires the specification of appropriate numbers of each of its constituent cell types, as well as their proper differentiation and correct positioning relative to each other. During Drosophila cardiogenesis, all three of these processes are controlled by jumeau (jumu) and Checkpoint suppressor homologue (CHES-1-like), two genes encoding forkhead transcription factors that we discovered utilizing an integrated genetic, genomic and computational strategy for identifying novel genes expressed in the developing Drosophila heart. Both jumu and CHES-1-like are required during asymmetric cell division for the derivation of two distinct cardiac cell types from their mutual precursor, and in symmetric cell divisions that produce yet a third type of heart cell. jumu and CHES-1-like control the division of cardiac progenitors by regulating the activity of Polo, a kinase involved in multiple steps of mitosis. This pathway demonstrates how transcription factors integrate diverse developmental processes during organogenesis.
Publication Title
Two forkhead transcription factors regulate the division of cardiac progenitor cells by a Polo-dependent pathway.
Sample Metadata Fields
Specimen part
View Samples- Drosophila melanogaster
- 53 Downloadable Samples
- Affymetrix Drosophila Genome Array (drosgenome1)
Description
An important but largely unmet challenge in understanding the mechanisms that govern formation of specific organs is to decipher the complex and dynamic genetic programs exhibited by the diversity of cell types within the tissue of interest. Here, we use an integrated genetic, genomic and computational strategy to comprehensively determine the molecular identities of distinct myoblast subpopulations within the Drosophila embryonic mesoderm at the time that cell fates are initially specified. A compendium of gene expression profiles was generated for primary mesodermal cells purified by flow cytometry from appropriately staged wild-type embryos and from twelve genotypes in which myogenesis was selectively and predictably perturbed. A statistical meta-analysis of these pooled datasetsbased on expected trends in gene expression and on the relative contribution of each genotype to the detection of known muscle genesprovisionally assigned hundreds of differentially expressed genes to particular myoblast subtypes. Whole embryo in situ hybridizations were then used to validate the majority of these predictions, thereby enabling true positive detection rates to be estimated for the microarray data. This combined analysis reveals that myoblasts exhibit much greater gene expression heterogeneity and overall complexity than was previously appreciated. Moreover, it implicates the involvement of large numbers of uncharacterized, differentially expressed genes in myogenic specification and subsequent morphogenesis. These findings also underscore a requirement for considerable regulatory specificity for generating diverse myoblast identities. Finally, to illustrate how the developmental functions of newly identified myoblast genes can be efficiently surveyed, a rapid RNA interference assay that can be scored in living embryos was developed and applied to selected genes. This integrated strategy for examining embryonic gene expression and function provides a substantially expanded framework for further studies of this model developmental system.
Publication Title
An integrated strategy for analyzing the unique developmental programs of different myoblast subtypes.
Sample Metadata Fields
No sample metadata fields
View Samples- Drosophila melanogaster
- 11 Downloadable Samples
- Affymetrix Drosophila Genome 2.0 Array (drosophila2)
Description
Homeodomain (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.
Publication Title
Molecular mechanism underlying the regulatory specificity of a Drosophila homeodomain protein that specifies myoblast identity.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 13 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Abstract
Publication Title
Gene expression profiles in skeletal muscle after gene electrotransfer.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 12 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The 8p11 myeloproliferative syndrome (EMS), also referred to as the stem cell leukemia/lymphoma syndrome, is a chronic myeloproliferative disorder that rapidly progresses into an acute leukemia. Molecularly, EMS is characterized by fusion of various partner genes to the FGFR1 gene, resulting in constitutive activation of the tyrosine kinase activity within FGFR1. The two most common fusion genes in human EMS are ZMYM2/FGFR1 (previously known as ZNF198/FGFR1) and BCR/FGFR1. To study the transcriptional programs becoming deregulated by the FGFR1 fusion genes, global gene expression analysis on human CD34+ cord blood cells expressing either of the fusion oncogenes ZMYM2/FGFR1 and BCR/FGFR1 was performed. As a reference gene we also included the more studied BCR/ABL1 fusion oncogene associated with chronic myeloid leukemia. We found that the 3 different fusion oncogenes had in common the upregulation of several genes involved in the JAK/STAT signalling pathway and also other sets of genes. However, the gene expression profiles were not identical, suggesting that both the tyrosine kinase containing gene and the partner gene would affect the transcription of downstream target genes.
Publication Title
Modeling the human 8p11-myeloproliferative syndrome in immunodeficient mice.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 57 Downloadable Samples
Illumina HiSeq 2000
Description
Background: Long non-coding RNAs (lncRNAs) are increasingly implicated as gene regulators and may ultimately be more numerous than protein-coding genes in the human genome. Despite large numbers of reported lncRNAs, reference annotations are likely incomplete due to their lower and tighter tissue-specific expression compared to mRNAs. An unexplored factor potentially confounding lncRNA identification is inter-individual expression variability. Here, we characterize lncRNA natural expression variability in human primary granulocytes. Results: We annotate granulocyte lncRNAs and mRNAs in RNA-seq data from ten healthy individuals, identifying multiple lncRNAs absent from reference annotations, and use this to investigate three known features (higher tissue-specificity, lower expression, and reduced splicing efficiency) of lncRNAs relative to mRNAs. Expression variability was examined in seven individuals sampled three times at one or more than one month intervals. We show that lncRNAs display significantly more inter-individual expression variability compared to mRNAs. We confirm this finding in 2 independent human datasets by analyzing multiple tissues from the GTEx project and lymphoblastoid cell lines from the GEUVADIS project. Using the latter dataset we also show that including more human donors into the transcriptome annotation pipeline allows identification of an increasing number of lncRNAs, but minimally affects mRNA gene number. Conclusions: A comprehensive annotation of lncRNAs is known to require an approach that is sensitive to low and tight tissue-specific expression. Here we show that increased inter-individual expression variability is an additional general lncRNA feature to consider when creating a comprehensive annotation of human lncRNAs or proposing their use as prognostic or disease markers. Overall design: We used PolyA+ RNA-seq data from human primary granulocytes of 10 healthy individuals to de novo annotate lncRNAs and mRNAs in this cell type and ribosomal depleted (total) RNA-seq data from seven of these individuals sampled three times to analyze lncRNA amd mRNA expression variability
Publication Title
Long non-coding RNAs display higher natural expression variation than protein-coding genes in healthy humans.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 6 Downloadable Samples
- Illumina HiSeq 2000
Description
Olfaction is one of the most crucial senses for vertebrates regarding foraging and social behavior. Therefore, it is of particular interest to investigate the sense of smell, its function on a molecular level, the signaling proteins involved in the process and the mechanism of required ion transport. In recent years, the precise role of the ion transporter NKCC1 in olfactory sensory neuron (OSN) chloride accumulation has been a controversial subject. NKCC1 is expressed in OSNs and is involved in chloride accumulation of dissociated neurons, but it had not been shown to play a role in mouse odorant sensation. To characterize transporter gene expression in NKCC1-/- mice, we examined the OE gene profile (Supplementary Table 1) using Illumina RNA-Seq to generate OE transcriptomes from NKCC1-/- and wild type mice. We analyzed RNA from OEs of male and female NKCC1+/+ (12 ± 1 weeks) and NKCC1-/- mice (16.5 ± 3.5 weeks, NMRI background); each RNA sample was prepared from an OE pool of 4 (mixed-gender pool RNA isolation) or 2 (gender RNA pool) different mice for each condition. Our data demonstrated the absence of a highly expressed ion transporter that could compensate for NKCC1. Overall design: The Illumina RNA-Seq protocol was utilized. In total, we amplified and sequenced up to 38 million 101 nt-long fragments from murine NKCC1+/+ and NKCC1-/- adult OEs.
Publication Title
Ion transporter NKCC1, modulator of neurogenesis in murine olfactory neurons.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
The JAK2 mutation V617F is detectable in a majority of patients with Ph-negative myeloproliferative neoplasms (MPN). Enforced expression of JAK2 V617F in mice induces myeloproliferation and bone marrow (BM) fibrosis suggesting a causal role for the JAK2 mutant in the pathogenesis of MPN. However, little is known about mechanisms and effector molecules contributing to JAK2 V617F-induced myeloproliferation and fibrosis. Here we show that JAK2 V617F promotes expression of oncostatin M (OSM) in neoplastic myeloid cells. Correspondingly, OSM was found to be overexpressed in the BM and elevated in the serum of patients with JAK2 V617F+ MPN. In addition, OSM secreted by JAK2 V617F+ cells stimulated growth of fibroblasts and microvascular endothelial cells and induced the production of angiogenic and profibrogenic cytokines (HGF, VEGF, and SDF-1) in BM fibroblasts. All effects of MPN cell-derived OSM were blocked by a neutralizing anti-OSM antibody, whereas the production of OSM in MPN cells was effectively suppressed by a pharmacologic JAK2 inhibitor or RNAi-mediated knockdown of JAK2. In summary, JAK2 V617F-mediated upregulation of OSM may contribute to fibrosis, neoangiogenesis, and the cytokine storm observed in JAK2 V617F+ MPN, suggesting that OSM could serve as a novel therapeutic target molecule in these neoplasms.
Publication Title
Identification of oncostatin M as a JAK2 V617F-dependent amplifier of cytokine production and bone marrow remodeling in myeloproliferative neoplasms.
Sample Metadata Fields
Cell line, Treatment
View Samples