Tip60 is a key histone acetyltransferase (HAT) enzyme that plays a central role in diverse biological processes critical for general cell function, however the chromatin-mediated cell-type specific developmental pathways that are dependent exclusively upon the HAT activity of Tip60 remain to be explored. Here, we investigate the role of Tip60 HAT activity in transcriptional control during multicellular development, in vivo by examining genome-wide changes in gene expression in a Drosophila model system specifically depleted for endogenous dTip60 HAT function. We show that amino acid residue E431 in the catalytic HAT domain of dTip60 is critical for the acetylation of endogenous histone H4 in our fly model in vivo, and demonstrate that dTip60 HAT activity is essential for multicellular development. Moreover, our results uncover a novel role for Tip60 HAT activity in controlling neuronal specific gene expression profiles essential for nervous system function as well as a central regulatory role for Tip60 HAT function in general metabolism.
Microarray analysis uncovers a role for Tip60 in nervous system function and general metabolism.
Specimen part
View SamplesActivated pancreatic stellate cells produce the fibrotic matrix in chronic pancreatitis and pancreatic cancer. In vitro protocols examining PSC biology have usually involved PSCs cultured on plastic, a non-physiological surface. However, PSCs cultured on physiological matrices e.g. MatrigelTM (normal basement membrane) and collagen (fibrotic pancreas), may have distinctly different behaviours compared to cells cultured on plastic. Therefore, we aimed to compare PSC gene expression after culture on plastic, MatrigelTM and collagen I.
Extracellular matrix composition significantly influences pancreatic stellate cell gene expression pattern: role of transgelin in PSC function.
Sex
View SamplesUsing mouse lung resident conventional CD11b+ dendritic cells (CD11b+ cDCs) in the context of house-dust mite (HDM)-driven allergic airway sensitization as a model, we aimed here to identify transcriptional events regulating the pro-Th2 activity of cDCs.
Interferon response factor-3 promotes the pro-Th2 activity of mouse lung CD11b<sup>+</sup> conventional dendritic cells in response to house dust mite allergens.
Sex, Specimen part
View SamplesAtopic dermatitis (AD) is the most common inflammatory skin disease, with high unmet need for new therapies that are safe for chronic use. Emerging data suggest that TH2-cytokines play important roles in a variety of allergic and atopic conditions, including asthma and AD. In early phase clinical trials, dupilumab (a fully human monoclonal antibody against IL-4R that potently blocks IL-4 and IL-13 signaling) rapidly and markedly improved clinical measures in adults with either asthma (with elevated eosinophil counts) or moderate-to-severe AD. The pathomechanisms that may be impacted by IL-4/13 blockade in these disease settings have not yet been characterized in detail.
Dupilumab improves the molecular signature in skin of patients with moderate-to-severe atopic dermatitis.
Specimen part, Treatment, Subject, Time
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 SamplesMouse neural stem cells were generated from conditional knockout mice (Cicflox/flox) or the wild trype control mice (Cic+/+). Cic is conditionally knocked out following expression of Cre-recombinase. Cre-recombinase was incorporated in vitro via adenoviral-Cre transduction.
<i>Cic</i> Loss Promotes Gliomagenesis via Aberrant Neural Stem Cell Proliferation and Differentiation.
Specimen part
View SamplesMouse neural stem cells were generated from conditional knock-in mice. Mutant IDH1 is conditionally expressed following expression of Cre-recombinase. Cre-recombinase was incorporated in vitro
Mutant IDH1 Disrupts the Mouse Subventricular Zone and Alters Brain Tumor Progression.
Specimen part
View SamplesUnderstanding the structure and interplay of cellular signalling pathways is one of the great challenges in molecular biology. Boolean Networks can infer signalling networks from observations of protein activation. In situations where it is difficult to assess protein activation directly, Nested Effect Models are an alternative. They derive the network structure indirectly from downstream effects of pathway perturbations. To date, Nested Effect Models cannot resolve signalling details like the formation of signalling complexes or the activation of proteins by multiple alternative input signals. Here we introduce Boolean Nested Effect Models (B-NEM). B-NEMs combine the use of downstream effects with the higher resolution of signalling pathway structures in Boolean Networks. We show that B-NEMs accurately reconstruct signal flows in simulated data. Using B-NEM we then resolve BCR signalling via PI3K and TAK1 kinases in BL2 lymphoma cell lines.
Analyzing synergistic and non-synergistic interactions in signalling pathways using Boolean Nested Effect Models.
Specimen part, Cell line, Treatment
View SamplesPcG protein complex PRC2 is a methyltransferase specific for histone H3 lysine27, and H3K27me3 is essential for stable transcription silencing. Less well known but quantitatively much more important is the genome-wide role of PRC2 that dimethylates ~70% of total H3K27. Here we show that H3K27me2 occurs in inverse proportion to transcriptional activity in genes and intergenic regions and its loss results in global transcriptional derepression proportionally greatest in previously silent or weakly transcribed regions. H3K27me2 levels are controlled by opposing roaming activities of PRC2 and the H3K27 demethylase dUTX. Unexpectedly, we find an equally pervasive distribution of histone H2A ubiquitylated at lysine 118 (H2AK118ub), attributed to the RING1 subunit of PRC1-type complexes. Overall design: Examination of global changes in transcription genome-wide when E(z) is inactivated by monitoring total RNA from E(z) temperature-sensitive cells at 25°C and 31°C in duplicate
Genome-wide activities of Polycomb complexes control pervasive transcription.
Cell line, Subject
View SamplesTo investigate the genes differentially induced by c-FLIP up-regulation by lentivirus infection in monocytes from healthy donors
Induction of immunosuppressive functions and NF-κB by FLIP in monocytes.
Disease
View Samples