Transfer RNA (tRNA) modifications enhance the efficiency, specificity and fidelity of translation in all organisms. The anticodon modification mcm5s2U34 is required for normal growth and stress resistance in yeast; mutants lacking this modification have numerous phenotypes. Mutations in the homologous human genes are linked to neurological disease. The yeast phenotypes can be ameliorated by overexpression of specific tRNAs, suggesting that the modifications are necessary for efficient translation of specific codons. We determined the in vivo ribosome distributions at single codon resolution in yeast strains lacking mcm5s2U. We found accumulations at AAA, CAA, and GAA codons, suggesting that translation is slow when these codons are in the ribosomal A site, but these changes appeared too small to affect protein output. Instead, we observed activation of the GCN4-mediated stress response by a non- canonical pathway. Thus, loss of mcm5s2U causes global effects on gene expression due to perturbation of cellular signaling. Overall design: WT yeast and mutants lacking anticodon tRNA modifications were grown in YPD, and subjected to ribosome footprint profiling (ribo-seq) and RNA-seq of poly-A selected RNA. Dataset contains biological replicates for WT, ?ncs6 and ?uba4. Technical replicates were also performed for all RNA-seq datasets (using a different poly-A selection method).
Loss of a conserved tRNA anticodon modification perturbs cellular signaling.
Cell line, Subject
View SamplesRON WT and RON KO at 5, 6, 7 week virgin mammary glands
The Ron receptor tyrosine kinase negatively regulates mammary gland branching morphogenesis.
Age
View SamplesThe BM-derived CD45+/Sca1+ cells are haematopoietic stem/progenitor cells that have the ability to circulate and migrate and engraft to the muscle tissue, and therefore they are of particular interest. Notably, these cells retain their haematopoietic potential, as revealed both by in vitro and in vivo assays; but they also acquire myogenic potential, as shown by their ability to participate in muscle regeneration. Whether, this latter remarkable ability is the result of the reprogramming of the BM-CD45+/Sca1+ cells and the activation of a myogenic molecular program within these cells, remains controversial. This study aims to clarify this aspect of the process, investigating the role of the muscle microenviroment and key myogenic transcription factors.
Bone marrow-derived hematopoietic cells undergo myogenic differentiation following a Pax-7 independent pathway.
No sample metadata fields
View SamplesExtracellular nucleotides are potent signaling molecules mediating cell-specific biological functions. We previously demonstrated that adenosine 5'-triphosphate (ATP) inhibits the proliferation while stimulating the migration, in vitro and in vivo, of human bone marrow-derived mesenchymal stem cells (BM-hMSC). Here, we investigated the effects of ATP on BM-hMSC differentiation capacity.
Extracellular purines promote the differentiation of human bone marrow-derived mesenchymal stem cells to the osteogenic and adipogenic lineages.
Specimen part, Treatment, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Role of CD34 antigen in myeloid differentiation of human hematopoietic progenitor cells.
No sample metadata fields
View SamplesIn order to investigate the role of CD34 antigen in haematopoietic commitment, we overexpressed the human CD34 cDNA in human CD34+ cells by retroviral gene transfer.
Role of CD34 antigen in myeloid differentiation of human hematopoietic progenitor cells.
No sample metadata fields
View SamplesIn order to investigate the role of CD34 antigen in haematopoietic commitment, we silenced the CD34 gene expression in CD34+ stem/progenitor cells using a siRNA approach.
Role of CD34 antigen in myeloid differentiation of human hematopoietic progenitor cells.
No sample metadata fields
View SamplesThe c-Myb transcription factor is highly expressed in immature hematopoietic cells and down-regulated during differentiation. To define the role of c-Myb in human hematopoietic lineage commitment, we studied the effects of its silencing during the commitment of human CD34+ Hematopoietic stem/progenitor cells. In CD34+ cells c-Myb silencing determined a cell cycle arrest in G0/G1 phase which strongly decreased the clonogenic efficiency, togheter with a reduction of erythroid colonies coupled with an increase of the macrophage and megakaryocyte ones. Moreover, morphological and flow cytometry data supported the preferential macrophage and megakaryocyte differentiation of c-Myb-silenced CD34+ cells. Taken together our data indicate that c-Myb is essential for the commitment along the erythroid and granulocyte lineages but not for the macrophage and megakaryocyte differentiation. Gene expression profiling of c-Myb-silenced CD34+ cells identified some potential c-Myb targets which can account for these effects, to study by Chromatin Immunoprecipitation and Luciferase Reporter Assay.
c-myb supports erythropoiesis through the transactivation of KLF1 and LMO2 expression.
No sample metadata fields
View SamplesThe c-Myb transcription factor is highly expressed in immature hematopoietic cells and down-regulated during differentiation. To define the role of c-Myb during the terminal differentiation of hematopoietic precursors, we studied the effects of its silencing in human primary CD14-myeloblasts, which maintain a granulo-monocyte differentiation bipotentiality. c-Myb-silenced myeloblasts were blocked in the G1 phase of the cell cycle at 24 hours post-nucleofection and subsequently were forced towards macrophage differentiation, as demonstrated by immunophenotypic and morphological analysis. Indeed, c-Myb-silenced CD14- cells differentiate to macrophage even after the treatment with ATRA 10-6 M, demonstrating that the c-Myb knockdown strongly impairs the ability of myeloblasts to differentiate to granulocytes. Gene expression profiling of c-Myb-silenced CD14- cells identified some potential c-Myb targets that can account for these effects.
c-myb supports erythropoiesis through the transactivation of KLF1 and LMO2 expression.
Specimen part, Time
View SamplesSeveral reports indicate that mesalazine (5-aminosalicylic acid or 5-ASA) is a promising candidate for the chemoprevention of Colo-Rectal Cancer (CRC) due to its ability to reach the purpose, yet avoiding at the same time the side effects that are usually determined by prolonged administrations of Non Steroidal Anti-Inflammatory Drugs. This activity of 5-ASA is probably the consequence of a number of effects determined on colon cancer cells and consisting of reduced proliferation, increased apoptosis and activation of cell cycle checkpoints. A recent observation has suggested that these effects could be mediated by the capacity of 5-ASA to interfere with the nuclear translocation of beta-catenin, in turn responsible for the inhibition of its transcription activity. The aim of our study was to better characterize the molecular mechanism by which 5-ASA inhibits the beta-catenin signaling pathway. To address this issue we assessed, by means of the Affymetrix microarray methodology, the transcriptome changes determined on Caco2 cells by a 96 h treatment with 20 mM mesalazine.
Mesalazine inhibits the beta-catenin signalling pathway acting through the upregulation of mu-protocadherin gene in colo-rectal cancer cells.
No sample metadata fields
View Samples