Rhabdomyosarcoma is a pediatric malignancy thought to arise from the uncontrolled proliferation of myogenic cells. Here, we have generated models of rhabdomyosarcoma in the zebrafish by inducing oncogenic KRASG12D expression at different stages during muscle development. Several zebrafish promoters were used including the cdh15 and rag2 promoters that drive gene expression in early muscle progenitors, and the mylz2 promoter that expresses in differentiating myoblasts. The tumors that developed differed in their ability to recapitulate normal myogenesis. cdh15:KRASG12D and rag2:KRASG12D fish developed tumors that displayed an inability to fully undergo muscle differentiation by histologic appearance and gene expression analyses. In contrast, mylz2:KRASG12D tumors more closely resembled mature skeletal muscle and were most similar to well-differentiated human rhabdomyosarcoma by gene expression. mylz2:KRASG12D fish showed significantly improved survival compared to cdh15:KRASG12D and rag2:KRASG12D fish. Tumor-propagating activity was enriched in myf5-expressing cell populations within all of the tumor types. Our results demonstrate that oncogene expression at different stages during muscle development has profound effects on the ability of tumor cells to recapitulate normal myogenesis, altering the tumorigenic capability of these cells.
Zebrafish rhabdomyosarcoma reflects the developmental stage of oncogene expression during myogenesis.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Peripheral Nerve Single-Cell Analysis Identifies Mesenchymal Ligands that Promote Axonal Growth.
Sex, Specimen part, Treatment
View SamplesPeripheral nerves provide a supportive growth environment for developing and regenerating axons and are essential for maintenance and repair of many non-neural tissues. This capacity has largely been ascribed to paracrine factors secreted by nerve-resident Schwann cells. Here, we used single-cell transcriptional profiling to identify ligands made by different injured rodent nerve cell types and have combined this with cell-surface mass spectrometry to computationally model potential paracrine interactions with peripheral neurons. These analyses show that peripheral nerves make many ligands predicted to act on peripheral and CNS neurons, including known and previously uncharacterized ligands. While Schwann cells are an important ligand source within injured nerves, more than half of the predicted ligands are made by nerve-resident mesenchymal cells, including the endoneurial cells most closely associated with peripheral axons. At least three of these mesenchymal ligands, ANGPT1, CCL11, and VEGFC, promote growth when locally applied on sympathetic axons. These data therefore identify an unexpected paracrine role for nerve mesenchymal cells and suggest that multiple cell types contribute to creating a highly pro-growth environment for peripheral axons.
Peripheral Nerve Single-Cell Analysis Identifies Mesenchymal Ligands that Promote Axonal Growth.
Sex, Specimen part, Treatment
View SamplesPeripheral nerves provide a supportive growth environment for developing and regenerating axons and are essential for maintenance and repair of many non-neural tissues. This capacity has largely been ascribed to paracrine factors secreted by nerve-resident Schwann cells. Here, we used single-cell transcriptional profiling to identify ligands made by different injured rodent nerve cell types and have combined this with cell-surface mass spectrometry to computationally model potential paracrine interactions with peripheral neurons. These analyses show that peripheral nerves make many ligands predicted to act on peripheral and CNS neurons, including known and previously uncharacterized ligands. While Schwann cells are an important ligand source within injured nerves, more than half of the predicted ligands are made by nerve-resident mesenchymal cells, including the endoneurial cells most closely associated with peripheral axons. At least three of these mesenchymal ligands, ANGPT1, CCL11, and VEGFC, promote growth when locally applied on sympathetic axons. These data therefore identify an unexpected paracrine role for nerve mesenchymal cells and suggest that multiple cell types contribute to creating a highly pro-growth environment for peripheral axons.
Peripheral Nerve Single-Cell Analysis Identifies Mesenchymal Ligands that Promote Axonal Growth.
Specimen part
View SamplesPeripheral nerves provide a supportive growth environment for developing and regenerating axons and are essential for maintenance and repair of many non-neural tissues. This capacity has largely been ascribed to paracrine factors secreted by nerve-resident Schwann cells. Here, we used single-cell transcriptional profiling to identify ligands made by different injured rodent nerve cell types and have combined this with cell-surface mass spectrometry to computationally model potential paracrine interactions with peripheral neurons. These analyses show that peripheral nerves make many ligands predicted to act on peripheral and CNS neurons, including known and previously uncharacterized ligands. While Schwann cells are an important ligand source within injured nerves, more than half of the predicted ligands are made by nerve-resident mesenchymal cells, including the endoneurial cells most closely associated with peripheral axons. At least three of these mesenchymal ligands, ANGPT1, CCL11, and VEGFC, promote growth when locally applied on sympathetic axons. These data therefore identify an unexpected paracrine role for nerve mesenchymal cells and suggest that multiple cell types contribute to creating a highly pro-growth environment for peripheral axons.
Peripheral Nerve Single-Cell Analysis Identifies Mesenchymal Ligands that Promote Axonal Growth.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Dedifferentiated Schwann Cell Precursors Secreting Paracrine Factors Are Required for Regeneration of the Mammalian Digit Tip.
Specimen part, Treatment
View SamplesMulti-tissue regenerative capacity is lost in adult mammals with the exception of the distal digit, which regenerates via largely-uncharacterized mechanisms. Here, we demonstrate that following adult mouse distal digit removal, nerve-associated Schwann cell precursors (N-SCPs) dedifferentiate and secrete growth factors that promote expansion of the blastema and digit regeneration. Specifically, when N-SCPs were dysregulated or ablated, mesenchymal precursor proliferation in the blastema was decreased, nail and bone regeneration were impaired, and regeneration could be rescued by transplantation of exogenous N-SCPs. We show that N-SCPs secreted factors that promoted self-renewal of mesenchymal precursors, and we used transcriptomic and proteomic analysis to define candidate factors. Two of these, oncostatin M (OSM) and PDGF-AA, were made by N-SCPs in the regenerating digit, and rescued the deficits in regeneration caused by loss of N-SCPs due to denervation. Since nerves innervate every peripheral tissue, these results have broad implications for mammalian tissue repair and regeneration.
Dedifferentiated Schwann Cell Precursors Secreting Paracrine Factors Are Required for Regeneration of the Mammalian Digit Tip.
Treatment
View SamplesMulti-tissue regenerative capacity is lost in adult mammals with the exception of the distal digit, which regenerates via largely-uncharacterized mechanisms. Here, we demonstrate that following adult mouse distal digit removal, nerve-associated Schwann cell precursors (N-SCPs) dedifferentiate and secrete growth factors that promote expansion of the blastema and digit regeneration. Specifically, when N-SCPs were dysregulated or ablated, mesenchymal precursor proliferation in the blastema was decreased, nail and bone regeneration were impaired, and regeneration could be rescued by transplantation of exogenous N-SCPs. We show that N-SCPs secreted factors that promoted self-renewal of mesenchymal precursors, and we used transcriptomic and proteomic analysis to define candidate factors. Two of these, oncostatin M (OSM) and PDGF-AA, were made by N-SCPs in the regenerating digit, and rescued the deficits in regeneration caused by loss of N-SCPs due to denervation. Since nerves innervate every peripheral tissue, these results have broad implications for mammalian tissue repair and regeneration.
Dedifferentiated Schwann Cell Precursors Secreting Paracrine Factors Are Required for Regeneration of the Mammalian Digit Tip.
Specimen part
View SamplesWe addressed changes in gene expression profile in response to
Role of PUG1 in inducible porphyrin and heme transport in Saccharomyces cerevisiae.
No sample metadata fields
View SamplesSmall RNAs (sRNA) that act by base pairing with trans-encoded mRNAs modulate metabolism in response to a variety of environmental stimuli. Here, we describe an Hfq-binding sRNA (FnrS) whose expression is induced upon a shift from aerobic to anaerobic conditions and which acts to down regulate the levels of a variety of mRNAs encoding metabolic enzymes. Anaerobic induction in minimal medium depends strongly on FNR but is also affected by ArcA and CRP. Whole genome expression analysis showed that the levels of at least 32 mRNAs are down regulated upon FnrS overexpression, 15 of which are predicted to base pair with FnrS by TargetRNA. The sRNA is highly conserved across its entire length in numerous enterobacteria, and mutation analysis revealed that two separate regions of FnrS base pair with different sets of target mRNAs. The majority of the target genes previously reported to be down regulated in an FNR-dependent manner lack recognizable FNR binding sites. We thus suggest that FnrS extends the FNR regulon and increases the efficiency of anaerobic metabolism by repressing the synthesis of enzymes that are not needed under these conditions.
Reprogramming of anaerobic metabolism by the FnrS small RNA.
No sample metadata fields
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