The success of targeted therapies hinges on our ability to understand the molecular and cellular mechanism of action of these agents. Here we modify various BET bromodomain inhibitors, an exemplar novel targeted therapy, to create functionally conserved compounds that are amenable to click-chemistry and can be used as molecular probes in vitro and in vivo. Using click-proteomics and click-sequencing we provide new mechanistic insights to explain the gene regulatory function of BRD4 and the transcriptional changes invoked by BET inhibitors. In mouse models of acute leukaemia, we use high resolution microscopy and flow cytometry to highlight the underappreciated heterogeneity of drug activity within tumour cells located in different tissue compartments. We also demonstrate the differential distribution and effects of the drug in normal and malignant cells in vivo. These data provide critical insights that reveal the cellular and molecular details for the efficacy and limitations of these agents. This study provides a framework for the pre-clinical assessment of other conventional and targeted therapies. Overall design: RNASeq of MV4;11 cell treated with DMSO, JQ1 or JQ1–PA
Click chemistry enables preclinical evaluation of targeted epigenetic therapies.
Specimen part, Cell line, Subject
View SamplesAnalysis of the transcriptome of mononuclear side population (SP) and main population (MP) cells of human fetal skeletal muscle from 12 human subjects of gestational age 14-18 weeks.
Regulation of myogenic progenitor proliferation in human fetal skeletal muscle by BMP4 and its antagonist Gremlin.
Specimen part
View SamplesAs duodenum is an important Vitamin D target organ, transcriptomic analyses were performed in this tissue.
A vitamin D receptor selectively activated by gemini analogs reveals ligand dependent and independent effects.
Age, Specimen part
View SamplesBRAF is the most frequently mutated gene in melanoma. Constitutive activation of mutant BRAFV600E leads to aberrant Ras-independent MAPK signaling and cell transformation. Inhibition of mutant BRAF is a current front-line therapy for such cases, with improved survival compared with chemotherapy. Unfortunately, reactivation of MAPK signaling by several mechanisms has been shown to cause drug resistance and disease recurrence. In this work, we describe the co-occurrence of an in-frame deletion within an amplified BRAFV600E locus, and a missense point mutation of the transcriptional repressor BCORL1, in vemurafenib-resistant A375 melanoma cells. Functional data confirmed that truncated p47BRAFV600E and mutant BCORL1Q1076H both contribute to resistance. Interestingly, either endogenous BCORL1 silencing or ectopic BCORL1Q1076H expression mimicked the effects of a CRISPR/Cas9-edited BCORL1Q1076H locus, suggesting a change-of-function mutation. Transcriptomic data confirmed this hypothesis. Finally, we show that the pan-RAF inhibitor sorafenib is not affected by expression of BRAF deletion variant and effectively synergizes with vemurafenib to block resistant cells, suggesting a possible intervention for this class of mutants. Overall design: Nine total samples: 3 parental plus 3 BCORL1-WT and 3 BCORL1-MUT overexpressing cells
Concomitant BCORL1 and BRAF Mutations in Vemurafenib-Resistant Melanoma Cells.
Cell line, Subject
View Sampleswe used technique that allows the molecular characterization of particular neuronal subpopulations based on their neuroanatomical projections and the locations of their cell bodies. This 'retro-TRAP' (translating ribosome affinity purification from retrogradely labeled neurons) approach relies on viral injection into an anatomical area targeted by the neurons of interest, followed by selective precipitation of ribosomes from retrogradely labeled cell bodies, and subsequent RNAseq analysis. Overall design: By comparing the mRNAs enriched in the NGC neurons which are retrogradely labeled due to viral injection into central thalamus, to gene expression of non-labeled surrounding cells in NGC, and then performing a comprehensive bioinformatics analysis of these results, we were able to identify genes enriched in these cells. This procedure allowed us to highlight genes and pathways unique to these neurons with projections ascending to thalamus, as compared to other cells in reticular NucleusGigantocellularis.
Molecular profiling of reticular gigantocellularis neurons indicates that eNOS modulates environmentally dependent levels of arousal.
Sex, Specimen part, Cell line, Subject
View SamplesWe studied the transcriptional profile in yeast cells in response to heterologous expression of mammalian activated AKT1
Heterologous mammalian Akt disrupts plasma membrane homeostasis by taking over TORC2 signaling in Saccharomyces cerevisiae.
No sample metadata fields
View SamplesWe studied the transcriptional profile in response to acute PtdIns-4,5P2 depletion induced by heterologous expression of a plasma membrane-directed version of mammalian PI3K catalytic subunit (p110-CAAX).
The yeast cell wall integrity pathway signals from recycling endosomes upon elimination of phosphatidylinositol (4,5)-bisphosphate by mammalian phosphatidylinositol 3-kinase.
No sample metadata fields
View SamplesThe restoration of catalytic activity to mutant enzymes by small molecules is well-established for in vitro systems. Here we show that the protein tyrosine kinase Src R388A mutant can be rescued in live cells using the small molecule imidazole. Cellular rescue of a v-Src homolog was rapid and reversible and conferred predicted oncogenic properties. Using chemical rescue in combination with mass spectrometry, six known Src kinase substrates were confirmed, and several new protein targets identified. Chemical rescue data suggests that c-Src is active under basal conditions. Rescue of R388A c-Src also allowed contributions of Src to the MAP kinase pathway to be clarified. This chemical rescue approach is likely to be of broad utility in cell signaling.
Chemical rescue of a mutant enzyme in living cells.
No sample metadata fields
View SamplesThe Anopheles gambiae midgut harbors bacteria that proliferate upon a blood feed. We used microarrays to examine the midgut gene expression response at early stages (3hours) after an artifitial meal containing heat killed bacteria.
A peroxidase/dual oxidase system modulates midgut epithelial immunity in Anopheles gambiae.
Age, Specimen part
View SamplesIn mammals body temperature fluctuates diurnally around a mean value of 36-37°C. Despite the small differences between minimal and maximal values, body temperature rhythms can drive robust cycles in gene expression in cultured cells and, likely, in, animals. Here we studied the mechanisms responsible for the temperature-dependent expression of Cold- Inducible RNA-Binding Protein (CIRBP). In NIH3T3 fibroblasts exposed to simulated mouse body temperature cycles Cirbp mRNA oscillates about 3-fold in abundance, as it does in mouse liver. This daily mRNA accumulation cycle is directly controlled by temperature oscillations and does not depend on the cells’ circadian clocks. Here, we show that the temperature-dependent accumulation of Cirbp mRNA is controlled primarily by the regulation of splicing efficiency, defined as the fraction of Cirbp pre-mRNA processed into mature mRNA. As revealed by genome-wide “approach-to-steady-kinetics”, this posttranscriptional mechanism is wide-spread in the temperature-dependent control of gene expression. Overall design: Cultured NIH3T3 cells seeded and kept at 37C degree for 4 hours before being switched to 33C and 38C. After 16 hours of incubation the temperature was shifted to 38C and 33C, respectively. Sample were then taken at 0, 1, 3, 6 and 9 hour after the temperature shift. Paired-end, strand-specific, total RNA-seq was performed over the samples at the respective time points using the Illumina HiSeq2500 platform.
Temperature regulates splicing efficiency of the cold-inducible RNA-binding protein gene Cirbp.
Specimen part, Subject, Time
View Samples