Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Collier/OLF/EBF-dependent transcriptional dynamics control muscle specification from cardiopharyngeal progenitors

ABSTRACT: In vertebrates, pluripotent pharyngeal mesoderm progenitors produce the cardiac precursors of the second heart field as well as the branchiomeric head muscles and associated stem cells. However, the cellular and molecular mechanisms underlying the transition from multipotent progenitors to distinct heart and muscle precursors remain obscured by the complexity of vertebrate embryos. Here, using the ascidian Ciona intestinalis as a simple chordate model for cardiopharyngeal development, we show that bipotent progenitors are transcriptionally primed to activate both heart and pharyngeal muscle regulatory programs, which become restricted to the corresponding precursors following a conserved pattern of asymmetric divisions. Localized expression of COE (Collier/OLF1/EBF) then orchestrates the transition to a pharyngeal muscle fate both by promoting an MRF (Myogenic Regulatory Factor)-associated core myogenic program in myoblasts and by maintaining an undifferentiated state in their sister precursors through Notch-mediated lateral inhibition. Using single cell lineage tracing, we show that the latter are stem-like muscle precursors, which form most of the juvenile body wall muscles following proliferation, self-renewal, re-activation of MRF, and migration. We discuss the implications of our findings for the development and evolution of the cardiopharyngeal mesoderm in chordates. We combined fluorescence-activated cell sorting (FACS) and whole genome transcription profiling following perturbations of COE function to characterize the transcriptional dynamics underlying the specification of heart and ASM precursors in the ascidian cardiopharyngeal lineage. We used whole genome transcription profiling of FACS-purified cell populations isolated from 21 hpf larvae expressing FoxF>COE, FoxF>COE::WRPW or the FoxF>NLS::lacZ control. To gain insights into the transcriptional dynamics underlying fate specification in the cardiopharyngeal lineage, we also purified B7.5-lineage cells from control embryos and larvae collected every two hours from 8 to 28 hpf. This time window encompasses all developmental transitions from early TVC specification till ASM ring formation and initial differentiation.

ORGANISM(S): Ciona intestinalis

SUBMITTER: Lionel Christiaen

PROVIDER: E-GEOD-54746 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Collier/OLF/EBF-dependent transcriptional dynamics control pharyngeal muscle specification from primed cardiopharyngeal progenitors.

Razy-Krajka Florian F Lam Karen K Wang Wei W Stolfi Alberto A Joly Marine M Bonneau Richard R Christiaen Lionel L

Developmental cell 20140501 3

In vertebrates, pluripotent pharyngeal mesoderm progenitors produce the cardiac precursors of the second heart field as well as the branchiomeric head muscles and associated stem cells. However, the mechanisms underlying the transition from multipotent progenitors to distinct muscle precursors remain obscured by the complexity of vertebrate embryos. Using Ciona intestinalis as a simple chordate model, we show that bipotent cardiopharyngeal progenitors are primed to activate both heart and pharyn ...[more]

PMID: 24794633

Similar Datasets

Project description:Dynamic gene expression programs determine multipotent cell states and fate choices during development. Multipotent progenitors for cardiomyocytes and branchiomeric head muscles populate the pharyngeal mesoderm of vertebrate embryos, but the mechanisms underlying cardiopharyngeal multipotency and heart vs. head muscle fate choices remain elusive. The tunicate Ciona emerged as a simple chordate model to study cardiopharyngeal development with unprecedented spatio-temporal resolution. We analyzed the transcriptome of single cardiopharyngeal lineage cells isolated at successive time points encompassing the transitions from multipotent progenitors to distinct first and second heart, and pharyngeal muscle precursors. We reconstructed the three cardiopharyngeal developmental trajectories, and characterized gene expression dynamics and regulatory states underlying each fate choice. Experimental perturbations and bulk transcriptome analyses revealed that ongoing FGF/MAPK signaling maintains cardiopharyngeal multipotency and promotes the pharyngeal muscle fate, whereas signal termination permits the deployment of a full pan-cardiac program and heart fate specification. We identified the Dach1/2 homolog as a novel evolutionarily conserved second-heart-field-specific factor and demonstrate, through lineage tracing and CRISPR/Cas9 perturbations, that it operates downstream of Tbx1/10 to actively suppress the first heart lineage program. This data indicates that the regulatory state of multipotent cardiopharyngeal progenitors determines the first vs. second heart lineage choice, and that Tbx1/10 acts as a bona fide regulator of cardiopharyngeal multi potency. We performed bulk RNAseq to profile the FACS purified Ciona Robusta Truck Ventral Cells (TVCs) with FGF-MAPK perturbation conditions to address the question- What is the role of FGF signaling pathway during early cardiopharyngeal specification. we performed bulk RNA sequencing of FACS-purified cardiopharyngeal lineage cells isolated from embryos and larvae expressing either a dominant negative form the fibroblast growth factor receptor (dnFGFR), or a constitutively active form of M-Ras (caM-Ras), the sole Ras homolog in Ciona, under the control of TVC-specific enhancers.

Project description:Dynamic gene expression programs determine multipotent cell states and fate choices during development. Multipotent progenitors for cardiomyocytes and branchiomeric head muscles populate the pharyngeal mesoderm of vertebrate embryos, but the mechanisms underlying cardiopharyngeal multipotency and heart vs. head muscle fate choices remain elusive. The tunicate Ciona emerged as a simple chordate model to study cardiopharyngeal development with unprecedented spatio-temporal resolution. We analyzed the transcriptome of single cardiopharyngeal lineage cells isolated at successive time points encompassing the transitions from multipotent progenitors to distinct first and second heart, and pharyngeal muscle precursors. We reconstructed the three cardiopharyngeal developmental trajectories, and characterized gene expression dynamics and regulatory states underlying each fate choice. Experimental perturbations and bulk transcriptome analyses revealed that ongoing FGF/MAPK signaling maintains cardiopharyngeal multipotency and promotes the pharyngeal muscle fate, whereas signal termination permits the deployment of a full pan-cardiac program and heart fate specification. We identified the Dach1/2 homolog as a novel evolutionarily conserved second-heart-field-specific factor and demonstrate, through lineage tracing and CRISPR/Cas9 perturbations, that it operates downstream of Tbx1/10 to actively suppress the first heart lineage program. This data indicates that the regulatory state of multipotent cardiopharyngeal progenitors determines the first vs. second heart lineage choice, and that Tbx1/10 acts as a bona fide regulator of cardiopharyngeal multi potency. 1823 FACS purified Ciona cardiopharyngeal progenitor cells at successive developmental stages (12, 14, 16, 18, 20 hpfs) have been sequenced in this research, encompassing the developmental spectrum from single multipotent progenitors to diverse fate-restricted progenitor cells. 1796 out of 1823 cells have reads successfully mapped to Ciona genome (i.e only 1796 samples have FPKM data in the *txt processed data files). We adopted multiple quality control criteria to filter out low quality single cell transcriptomes, the contaminating subpopulations and the doublets. Eventually, 848 high-quality cells were retained for further analysis. Based on previously identified cell type specific markers and the well established lineage tree, we identified all five cardiopharyngeal progenitor subtypes (TVC, STVC, ASM, FHP, SHP) and in silico reconstructed three unidirectional trajectories corresponding to the specification of pharyngeal and cardiac fate. Our study enabled us to characterize the global gene expression patterns of heterogeneous cardiopharyngeal progenitors, and interrogate the spatial-temporal dynamics of cardiopharyngeal specification.

Project description:The transcriptional control of CNS myelin gene expression is poorly understood. Here we identify gene model 98, which we have named Myelin-gene Regulatory Factor (MRF), as a transcriptional regulator required for CNS myelination. Within the CNS, MRF is specifically expressed by postmitotic oligodendrocytes. MRF is a nuclear protein containing an evolutionarily conserved DNA binding domain homologous to a yeast transcription factor. Knockdown of MRF in oligodendrocytes by RNA interference prevents expression of most CNS myelin genes; conversely, overexpression of MRF within cultured oligodendrocyte progenitors or the chick spinal cord promotes expression of myelin genes. In mice lacking MRF within the oligodendrocyte lineage, pre-myelinating oligodendrocytes are generated but display severe deficits in myelin gene expression and fail to myelinate. These mice display severe neurological abnormalities, and die due to seizures during the third postnatal week. These findings establish MRF as a critical transcriptional regulator essential for oligodendrocyte maturation and CNS myelination. We used microarrays to compare cultured oligodendrocytes (differentiated in vitro for 4 days) from MRF conditional knockouts and control litteramates to look at the effects of MRF deficiency on myelin gene expression. Mouse OPCs grown in vitro in the presence of PDGF serve as a baseline for gene expression prior to differentiation. Mouse OPCs from MRF conditional knockout (MRF fl/fl, Olig2 wt/cre) mice and control littermates (MRF wt/fl; Olig2 wt/cre) were isolated from enzymatically dissociated P7 mouse brains as previously described (Cahoy et al., 2008), positively immunopanning for PDGFR-alpha following a depletion of microglia with BSL1. Cells were grown in defined serum-free media as previously described (Dugas et al., 2006), but with the addition of 2% B-27 (Invitrogen). Cells were proliferated for several days in the presence of PDGF-AA (10 ng/ml, PeproTech) and then differentiation induced by withdrawal of PDGF-AA and addition of triiodothyronine (T3) (40 ng/ml; Sigma). RNA was isolated from cells 4 days after induction of differentiation; OPCs maintained in PDGF-AA serve as a baseline of OPC gene expression. Total RNA was isolated from cells with the RNeasy micro kit (Qiagen, Valencia, CA) using Qiagen on-column DNase treatment to remove any contaminating genomic DNA. The integrity of RNA was assessed using an Agilent 2100 Bioanalyzer (Agilent Technologies) and RNA concentration was determined using a NanoDrop ND-1000 spectrophotometer (NanoDrop, Rockland, DE). Biotinylated cRNAs for hybridization to Affymetrix 3'-arrays were prepared from 1ug total RNA using the Affymetrix two-cycle target labeling assay with spike in controls (Affymetrix Inc., Santa Clara, CA, 900494). Labeled-cRNA was fragmented and hybridized to Mouse Genome 430 2.0 Arrays (3'-arrays, Affymetrix, 900495) following the manufacturer's protocols. Raw image files were processed using Affymetrix GCOS 1.3 software to calculate individual probe cell intensity data and generate CEL data files. Using GCOS and the MAS 5.0 algorithm, intensity data was normalized per chip to a target intensity TGT value of 500 and expression data and present/absent calls for individual probe sets calculated. Gene symbols and names for data analyzed with the MAS 5.0 algorithm were from the Affymetrix Netaffx Mouse430_2 annotations file (http://www.affymetrix.com/support/technical/byproduct.affx?product=moe430-20). Quality control was performed by examining raw DAT image files for anomalies, confirming each GeneChip array had a background value less than 100, monitoring that the percencelle present calls was appropriate for the cell type, and inspecting the poly(A) spike in controls, housekeeping genes, and hybridization controls to confirm labeling and hybridization consistency.

Dataset Information

Collier/OLF/EBF-dependent transcriptional dynamics control muscle specification from cardiopharyngeal progenitors

Publications

Collier/OLF/EBF-dependent transcriptional dynamics control pharyngeal muscle specification from primed cardiopharyngeal progenitors.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure