Metastasis is the leading cause of death for cancer patients. Consequently it is imperative that we improve our understanding of the molecular mechanisms that underlie progression of tumour growth towards malignancy. Advances in genome characterisation technologies have been very successful in identifying commonly mutated or misregulated genes in a variety of human cancers. However the difficulty in evaluating whether these candidate genes drive tumour progression remains a major challenge. Using the genetic amenability of Drosophila melanogaster we generated tumours with specific genotypes in the living animal and carried out a detailed systematic loss-of-function analysis to identify conserved genes that enhance or suppress epithelial tumour progression. This enabled the discovery of functional cooperative regulators of invasion and the establishment of a network of conserved invasion suppressors. This includes constituents of the cohesin complex, which can either promote individual or collective invasion, depending on the severity of effect on cohesin function.
A Genetic Analysis of Tumor Progression in Drosophila Identifies the Cohesin Complex as a Suppressor of Individual and Collective Cell Invasion.
Cell line
View SamplesClinical symptoms of dengue virus (DENV) infection, the most prevalent arthropod-borne viral disease, range from classical mild dengue fever to severe, life-threatening dengue shock syndrome. However, most DENV infections cause few or no symptoms. Asymptomatic DENV-infected patients provide a unique opportunity to decipher the host immune responses leading to virus elimination without negative impact on an individuals health. We used an integrated approach of transcriptional profiling and immunological analysis to compare a Cambodian population of strictly asymptomatic viremic individuals with clinical dengue patients. Whereas inflammatory pathways and innate immune response pathways were similar between asymptomatic individuals and clinical dengue patients, expression of proteins related to antigen presentation and subsequent T and B cell activation pathways were differentially regulated, independent of viral load and previous DENV infection history. Feedback mechanisms controlled the immune response in asymptomatic viremic individuals, as demonstrated by increased activation of T cell apoptosis-related pathways and FcRIIB signaling associated with decreased anti-DENV specific antibody concentrations. Taken together, our data illustrate that symptom-free DENV infection in children is associated with determined by increased activation of the adaptive immune compartment and proper control mechanisms, leading to elimination of viral infection without excessive immune activation, with implications for novel vaccine development strategies
Increased adaptive immune responses and proper feedback regulation protect against clinical dengue.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesTranscriptome analysis of total RNA samples from human cell line (LAM 621-101, female)
Post-transcriptional Regulation of De Novo Lipogenesis by mTORC1-S6K1-SRPK2 Signaling.
Sex, Specimen part, Cell line
View SamplesThe aim of this study was to assess the impact of oocyte competence on subsequent fertility. Based on knowledge already accessible in mammals and on bioinformatics tools including the chicken genome sequence, we focused on the expression of genes involved in the processes of fertilization and of early embryo development. The study was performed using two complementary approaches: a descriptive study of standard laying hens and then a differential study performed with hens from experimental lines expressing broad variations of achieved fertility (approximately 20 per cent). A differential kinetic study is performed on INRA lines selected on the basis of their fertility potential in purpose of hopefully access gene markers of fertility performance.
Identification of germinal disk region derived genes potentially involved in hen fertility.
No sample metadata fields
View SamplesThe aim of this study was to assess the impact of oocyte competence on subsequent fertility. Based on knowledge already accessible in mammals and on bioinformatics tools including the chicken genome sequence, we focused on the expression of genes involved in the processes of fertilization and of early embryo development.
Search for the genes involved in oocyte maturation and early embryo development in the hen.
No sample metadata fields
View SamplesSR proteins are well-characterized RNA binding proteins that promote exon inclusion by binding to exonic splicing enhancers (ESEs). However, it has been unclear whether regulatory rules deduced on model genes apply generally to activities of SR proteins in the cell. Here, we report global analyses of two prototypical SR proteins SRSF1 (SF2/ASF) and SRSF2 (SC35) using splicing-sensitive arrays and CLIP-seq on mouse embryo fibroblasts (MEFs). Unexpectedly, we find that these SR proteins promote both inclusion and skipping of exons in vivo, but their binding patterns do not explain such opposite responses. Further analyses reveal that loss of one SR protein is accompanied by coordinated loss or compensatory gain in the interaction of other SR proteins at the affected exons. Therefore, specific effects on regulated splicing by one SR protein actually depend on a complex set of relationships with multiple other SR proteins in mammalian genomes. Overall design: SRSF1 and SRSF2 CLIP-seq
Genome-wide analysis reveals SR protein cooperation and competition in regulated splicing.
Specimen part, Subject
View SamplesTo identify gene(s) that are modified in their relative expression levels in the Potocki-Lupski Syndrome mouse model and map to the rearranged region, i.e. possible candidate genes at the source of the PTLS-like phenotypes shown by the PTLS mouse, we comp
Abnormal social behaviors and altered gene expression rates in a mouse model for Potocki-Lupski syndrome.
No sample metadata fields
View SamplesIn the clinical setting, mutations in the CFTR gene enhance the inflammatory response to P. aeruginosa (PA01) infection, but measurements of the inflammatory response to pathogen stimulation by isolated airway epithelia can yield variable results. In this series, we exposed CFBE41o- cells over-expressing F508/F508 CFTR and CFBE41o- cells rescued with wt-CFTR to P. aeruginosa biofilms. P. aeruginosa elicited a more robust increase in cytokine and chemokine expression (e.g., IL-8, CXCL2, CXCL3, CXCR4 and TNF-) in CFBE-wt-CFTR cells compared to CFBE-F508-CFTR cells. These results demonstrate that CFBE41o- cells complemented with wt-CFTR mount a more robust inflammatory response to P. aeruginosa than CFBE41o- F508/F508-CFTR cells.
Does the F508-CFTR mutation induce a proinflammatory response in human airway epithelial cells?
Specimen part
View SamplesCystic fibrosis transmembrane conductance regulator (Cftr) knockout mice present the clinical features of low body weight and intestinal disease permitting an assessment of the interrelatedness of these phenotypes in a controlled environment. To identify intestinal alterations which affect body weight in CF mice the histological phenotypes of crypt-villus axis height, goblet cell hyperplasia, and mast cell infiltrate were measured, cardiac blood samples assessed, and gene expression profiling of the ileum was completed for 12 week old (C57BL/6xBALB) F2 Cftrtm1UNC and non-CF mice presenting a range of body weight. Crypt-villus axis height decreased with increasing weight in CF, but not control, mice. Goblet cell hyperplasia and mast cell infiltration in the submucosa and muscularis externa layers of the CF intestine, were identified to be independent of bodyweight. Blood triglyceride levels were found to be significantly lower in CF mice than control mice (p = 3.02 x 10-5) but were not dependent on CF mouse body weight. By expression profiling, genes of DNA replication and lipid metabolism were among those altered in CF mice relative to non-CF controls; and no differences in gene expression were measured between samples from CF mice in the 25th and 75th percentile for weight. This study indicates that the absence of Cftr leads to altered morphology in the CF intestine the extent of which is correlated with body weight in CF mice while CF related changes in blood triglyceride levels and in the intestinal gene expression profile were not dependent on body weight in this model.
Intestinal phenotype of variable-weight cystic fibrosis knockout mice.
Sex
View SamplesThe epigenetic changes of the chromatin represent an attractive molecular substrate for adaptation to the environment. We examined here the role of CBP, a histone acetyltransferase involved in mental retardation, in the genesis and maintenance of long-lasting systemic and behavioral adaptations to environmental enrichment (EE). Morphological and behavioral analyses demonstrated that EE ameliorates deficits associated to CBP-deficiency. However, CBP-deficient mice also showed a strong defect in environment-induced neurogenesis and impaired EE-enhanced spatial navigation and patter separation ability. These defects correlated with an attenuation of the transcriptional program induced in response to EE and with deficits in histone acetylation at the promoters of EE-regulated, neurogenesis-related genes. Additional experiments in CBP restricted and inducible knockout mice indicated that environment-induced adult neurogenesis is extrinsically regulated by CBP function in mature granule cells. Overall, our experiments demonstrate that the environment alters gene expression by impinging on activities involved in modifying the epigenome and identify CBP-dependent transcriptional neuroadaptation as an important mediator of EE-induced benefits, a finding with important implications for mental retardation therapeutics.
CBP is required for environmental enrichment-induced neurogenesis and cognitive enhancement.
Sex, Age, Specimen part
View Samples