Binding of the Capicua repressor in response to pulses of ERK signaling in the early Drosophila embryo
Ontology highlight
ABSTRACT:
ORGANISM(S): Drosophila melanogaster
PROVIDER: GSE130584 | GEO | 2020/03/05
REPOSITORIES: GEO
Similar Datasets
Project description:Binding of the Capicua repressor in response to pulses of ERK signaling in the early Drosophila embryo
| PRJNA540683 | ENA
Project description:Analysis of cerebella from Capicua (Cic) mutant mice and wild-type controls at 28 days of age (P28). Spinocerebellar ataxia type 1 (SCA1) is a fatal neurodegenerative disease caused by expansion of a translated CAG repeat in Ataxin-1 (ATXN1). The transcriptional repressor Cic binds directly to Atxn1 and plays a key role in SCA1 pathogenesis. Two isoforms of Cic, long (Cic-L) and short (Cic-S), are transcribed from alternative promoters. Using embryonic stem cells in which the Cic locus was targeted by an insertion of a genetrap cassette between exon 1 of the Cic-L isoform and exon 1 of the Cic-S isoform, we generated mice that carried this allele and backcrossed these onto a Swiss Webster (CD-1) strain for >6 generations. The resulting Cic-L-/- mice completely lack the Cic-L isoform with ~10% of Cic-S remaining. These data were used to compare with previous microarray data to determine the Cic-depedent pathogenic mechanisms in SCA1. Total RNA from cerebella of wild-type (n=4) and Capicua mutant mice (n=4) at 28 days of age was prepared and labeled according the manufacturer's protocols for the Affymetrix Mouse Gene 1.0 ST Array.
2011-11-07 | E-GEOD-32051 | biostudies-arrayexpress
Project description:Activation of Map kinase/Erk signalling downstream of fibroblast growth factor (Fgf) tyrosine kinase receptors regulates gene expression required for mesoderm induction and patterning of the anteroposterior axis during Xenopus development. We have proposed that a subset of Fgf target genes are activated in the embyo in response to inhibition of a transcriptional repressor. Here we investigate the hypothesis that Cic (Capicua), which was originally identified as a transcriptional repressor negatively regulated by receptor tyrosine kinase/Erk signalling in Drosophila, is involved in regulating Fgf target gene expression in Xenopus. We characterise Xenopus Cic and show that it is widely expressed in the embryo. Fgf overexpression or ectodermal wounding, both of which potently activate Erk, reduce Cic protein levels in embryonic cells. A similar mechanism of Cic protein degradation downstream of the Torso receptor tyrosine kinase receptor negatively regulates Cic activity in Drosophila. In keeping with our hypothesis, we show that Cic knockdown and Fgf overexpression have overlapping effects on embryo development and gene expression. Transcriptomic analysis identifies a cohort of genes that are up-regulated by Fgf overexpression and Cic knockdown. We investigate two of these genes, fos and rasl11b, which, respectively, encode a leucine zipper transcription factor and a ras family GTPase, as putative targets of the proposed Fgf/Erk/Cic axis. We identify Cic consensus binding sites in a highly conserved region of intron 1 in the fos gene and Cic sites in the upstream regions of several other Fgf/Cic co-regulated genes, including rasl11b. We show that expression of fos and rasl11b is blocked in the early mesoderm when Fgf and Erk signalling is inhibited. In addition, we show that fos and rasl11b expression is associated with the Fgf independent activation of Erk at the site of ectodermal wounding. Our data support a role for a Fgf/Erk/Cic axis in regulating a subset of Fgf target genes during gastrulation and is suggestive that Erk signalling is involved in regulating Cic target genes at the site of ectodermal wounding.
2023-05-05 | GSE228699 | GEO
Project description:The HMG-box protein Capicua (Cic) is a conserved transcriptional repressor that functions downstream of receptor tyrosine kinase (RTK) signaling pathways in a relatively simple switch: in the absence of signaling, Cic represses RTK-responsive genes by binding to nearly invariant sites in DNA, whereas activation of RTK signaling downregulates Cic activity, leading to derepression of its targets. This mechanism controls gene expression in both Drosophila and mammals, but whether Cic can also function via other regulatory mechanisms remains unknown. Here we characterize an RTK-independent role of Cic in regulating spatially restricted expression of Toll/IL-1 signaling targets in Drosophila embryogenesis. We show that Cic represses those targets by binding to suboptimal DNA sites of lower affinity than its known consensus sites. This binding depends on Dorsal/NF-kB, which translocates into the nucleus upon Toll activation and binds next to the Cic sites. As a result, Cic binds to and represses Toll targets only in regions with nuclear Dorsal. These results reveal a new mode of Cic regulation unrelated to the well-established RTK-Cic depression axis and implicate cooperative binding in conjunction with low-affinity binding sites as an important mechanism of enhancer regulation. Given that Cic plays a role in many developmental and pathological processes in mammals, our results raise the possibility that some of these Cic functions are independent of RTK regulation and may depend on cofactor-assisted DNA binding.
2018-01-05 | GSE104839 | GEO
Project description:Analysis of cerebella from Capicua (Cic) mutant mice and wild-type controls at 28 days of age (P28). Spinocerebellar ataxia type 1 (SCA1) is a fatal neurodegenerative disease caused by expansion of a translated CAG repeat in Ataxin-1 (ATXN1). The transcriptional repressor Cic binds directly to Atxn1 and plays a key role in SCA1 pathogenesis. Two isoforms of Cic, long (Cic-L) and short (Cic-S), are transcribed from alternative promoters. Using embryonic stem cells in which the Cic locus was targeted by an insertion of a genetrap cassette between exon 1 of the Cic-L isoform and exon 1 of the Cic-S isoform, we generated mice that carried this allele and backcrossed these onto a Swiss Webster (CD-1) strain for >6 generations. The resulting Cic-L-/- mice completely lack the Cic-L isoform with ~10% of Cic-S remaining. These data were used to compare with previous microarray data to determine the Cic-depedent pathogenic mechanisms in SCA1.
2011-11-07 | GSE32051 | GEO
Project description:Rearrangements between genes can yield neomorphic fusions that drive oncogenesis. Fusion oncogenes are made up of fractional segments of the partner genes that comprise them, with each partner potentially contributing some of its own function to the nascent fusion oncoprotein. Clinically, fusion oncoproteins driving one diagnostic entity are typically clustered into a single molecular subset and are often treated a similar fashion. However, knowledge of where specific fusion breakpoints occur in partner genes, and the resulting retention of functional domains in the fusion, is an important determinant of fusion oncoprotein activity and may differ between patients. This study investigates this phenomena through the example of CIC::DUX4, a fusion between the transcriptional repressor capicua (CIC) and the double homeobox 4 gene (DUX4), which drives an aggressive subset of undifferentiated round cell sarcoma. Using a harmonized dataset of over 100 patient fusion breakpoints from the literature, we show that most bona fide CIC::DUX4 fusions retain the C1 domain, which is known to contribute to DNA binding by wild type CIC. Mechanistically, deletion or mutation of the C1 domain reduces, but does not eliminate, activation of CIC target genes by CIC::DUX4. We also find that expression of C1-deleted CIC::DUX4 is capable of exerting intermediate transformation-related phenotypes compared with those imparted by full-length CIC::DUX4, but was not sufficient for tumorigenesis in a subcutaneous mouse model. In summary, our results suggest a supercharging role for the C1 domain in the activity of CIC::DUX4.
2024-06-06 | GSE269295 | GEO
Project description:Rearrangements between genes can yield neomorphic fusions that drive oncogenesis. Fusion oncogenes are made up of fractional segments of the partner genes that comprise them, with each partner potentially contributing some of its own function to the nascent fusion oncoprotein. Clinically, fusion oncoproteins driving one diagnostic entity are typically clustered into a single molecular subset and are often treated a similar fashion. However, knowledge of where specific fusion breakpoints occur in partner genes, and the resulting retention of functional domains in the fusion, is an important determinant of fusion oncoprotein activity and may differ between patients. This study investigates this phenomena through the example of CIC::DUX4, a fusion between the transcriptional repressor capicua (CIC) and the double homeobox 4 gene (DUX4), which drives an aggressive subset of undifferentiated round cell sarcoma. Using a harmonized dataset of over 100 patient fusion breakpoints from the literature, we show that most bona fide CIC::DUX4 fusions retain the C1 domain, which is known to contribute to DNA binding by wild type CIC. Mechanistically, deletion or mutation of the C1 domain reduces, but does not eliminate, activation of CIC target genes by CIC::DUX4. We also find that expression of C1-deleted CIC::DUX4 is capable of exerting intermediate transformation-related phenotypes compared with those imparted by full-length CIC::DUX4, but was not sufficient for tumorigenesis in a subcutaneous mouse model. In summary, our results suggest a supercharging role for the C1 domain in the activity of CIC::DUX4.
2024-10-16 | GSE279546 | GEO
Project description:Global phosphoproteomics can reveal signaling cascades in unprecedented detail. The SCF/KIT axis represents a vital hematopoietic receptor tyrosine kinase (RTK) system with gain-of-function mutations prompting the development of mastocytosis and leukemia. Here, we employed a label-free phosphoproteomics profiling strategy to provide the first comprehensive portrayal of SCF-triggered phosphosignaling. Employing untransformed skin-derived mast cells expressing vast amounts of KIT, we uncover around 10,500 class-I-phosphosites following ligand-induced KIT dimerization. Apart from STAT5, the MEK/ERK cascade (including upstream and downstream events) stood out as highly stimulatable by SCF compared to less impacted PI3K/Akt>p38>JNK, a pattern validated by time-resolved immunoblotting. Direct comparison between MEK/ERKÕs and PI3KÕs support of basic programs (anti-apoptosis, cell cycle progression) revealed equipotency with substantial redundancy between the modules. In functional outputs, ERK showed dominance over PI3K regarding cytokine stimulation (TNF-a, IL-8, LIF, OSM) and was the only contributor in the induction of immediate early genes (Fos, JunB, Egr1). Our proteome-wide screen also found Å1,000 phosphosites currently undescribed in databases, pertaining to multiple protein classes. Among candidates, capicua (and components of its network) experienced massive phosphorylation by SCF. Perturbation with capicua by RNA interference unveiled its function as a potent KIT repressor, whose deregulation may contribute to the development of mastocytosis. We demonstrate the utility of an unbiased approach to uncover single protein entities and entire networks activated by RTKs, that can be surveyed experimentally. This rich resource enhances our understanding of RTK-elicited signaling networks and can serve as a benchmark to identify pathological processes, e.g. under circumstances of KIT deregulation.
2022-11-15 | PXD028252 | Pride
Project description:CIC is a HMG box-containing transcriptional repressor evolutionarily conserved from C. elegans to human. It's known to associate with various types of cancer but physiological function of CIC remain largely unknown. In this study, we characterized Cic hypomorphic (Cic-L-/-) mice and identified critical roles for of CIC in drug metabolism and bile acid homeostasis. Total RNA obtained from isolated liver tissue of Cic-L-/- mouse compared to liver tissue of normal mouse
2015-04-15 | E-GEOD-60375 | biostudies-arrayexpress
Project description:Extracellular signal-regulated kinase (ERK) coordinates cellular responses to a range of stimuli by phosphorylating its numerous substrates. One of these substrates, Capicua (Cic), is a transcriptional repressor that was first identified in Drosophila and has been implicated in a number of human diseases. Here we use a chemical biology approach to map the binding interface of ERK and Cic. The noncanonical amino acid p-azidophenylalanine (AzF) was introduced into the ERK-binding region of Drosophila Cic, and photocrosslinking and tandem mass spectrometry were used to pinpoint its binding site on ERK. We also identified the ERK-binding region of human Cic and showed that it binds to the same site on ERK despite lacking conservation with the Drosophila Cic binding region. Finally, we mapped the amino acids involved in human Cic binding to ERK using AzF-labeled ERK. These results reveal the molecular details of the ERK-Cic interaction and demonstrate that the photocrosslinking approach is complementary to existing methods for mapping kinase-substrate binding interfaces.
| S-EPMC4507193 | biostudies-literature