Snail1 transcriptional factor is essential for triggering epithelial-to-mesenchymal transition (EMT) and inducing tumor cell invasion. We report here that Snail1 plays also a key role in tumor associated fibroblasts since is necessary for enhancement by these cells on epithelial cells tumor invasion. Snail1 expression in fibroblast requires signals derived from tumor cells such as TGF-b; reciprocally, in fibroblasts Snail1 organizes a complex program that favors collective invasion of epithelial cells at least in part by the secretion of diffusible signaling molecules, such as prostaglandin E2. The capability of human or murine tumor-derived cancer associated fibroblasts to promote tumor invasion is associated to Snail1 expression and obliterated by Snail1 depletion. In vivo experiments show that tumor cells co-transplanted with Snail1 depleted fibroblasts show lower invasion than those xenografted with control fibroblasts. Finally Snail1 depletion in mice prevents the formation of breast tumors and decreased their invasion. Therefore, these results demonstrate that the role of Snail1 in tumor invasion is not limited to its effect in EMT but dependent on its expression in stromal fibroblasts where it orchestrates its activation and the crosstalk with epithelial cells.
Snail1-Dependent Activation of Cancer-Associated Fibroblast Controls Epithelial Tumor Cell Invasion and Metastasis.
Specimen part
View SamplesGroup living animals must be able to express different behavior profiles depending on their social status. This implies that the same genotype may translate into different behavioral phenotypes through socially driven differential gene expression. Here we show for the first time that what triggers the switch between status-specific neurogenomic states is not the objective structure of the social interaction but rather the subjects perception of its outcome. For this purpose we had male zebrafish fight either a real opponent or their own image on a mirror. Massive changes in the brain transcriptome were observed in real opponent fighters, which experience either a victory or a defeat. In contrast, mirror fighters, which had no information on fight outcome despite expressing aggressive behavior, failed to activate a neurogenomic response. These results indicate that, even in cognitively simple organisms such as zebrafish, neurogenomic responses underlying changes in social status rely on cognitive appraisal.
Assessment of fight outcome is needed to activate socially driven transcriptional changes in the zebrafish brain.
Specimen part
View SamplesThe change of genome-wide transcription profiles as a result of Gis1 overexpression is monitored by comparing the transcriptomes isolated from cells where Gis1 overexpression is switched on or off. GIS1 was cloned into pCM190 vector under the control of the tetO7 promoter. The promoter is switched on when there is no doxycycline but off with doxycycline (20ug/ml). Cells were grown in medium with doxycycline, harvested, washes twice in sterile water, resuspended in the same medium with doxycycline (Dox+) or without doxycycline (dox-) and grown for additional 6 hours. Samples were taken for each condition at 3 and 6 hours. Time 0 sample was taken before resuspension.
The transcription activity of Gis1 is negatively modulated by proteasome-mediated limited proteolysis.
Subject, Compound, Time
View SamplesThe highly conserved herpesvirus glycoprotein complex, gB/gH-gL, mediates membrane fusion during virion entry and cell-cell fusion. Varicella-zoster virus (VZV) characteristically forms multi-nucleated cells, or syncytia, during the infection of human tissues but little is known about this process. The cytoplasmic domain of VZV gB (gBcyt) has been implicated in cell-cell fusion regulation because a gB[Y881F] substitution causes hyperfusion. The gBcyt regulation is necessary for VZV pathogenesis as the hyperfusogenic mutant gB[Y881F] is severely attenuated in human skin xenografts. In this study, gBcyt regulated fusion was investigated by comparing melanoma cells infected with wild type-like VZV or hyperfusogenic mutants. The gB[Y881F] mutant exhibited dramatically accelerated syncytia formation in melanoma cells caused by fusion of infected cells with many uninfected cells, increased cytoskeleton reorganization and rapid displacement of nuclei to dense central structures when compared to pOka using live cell confocal microscopy. VZV and human transcriptomes were concurrently investigated using RNA-seq to identify viral and cellular responses induced when the gBcyt regulation was disrupted by the gB[Y881F] substitution. The expression of four vital VZV genes, ORF61 and glycoproteins, gC, gE and gI, was significantly reduced at 36 hours post infection for the hyperfusogenic mutants. Importantly, hierarchical clustering demonstrated an association of differential gene expression with dysregulated gBcyt-mediated fusion. A subset of Ras GTPase genes linked to membrane remodeling were upregulated in cells infected with the hyperfusogenic mutants. These data implicate the gBcyt in the regulation gB fusion function that, if unmodulated, triggers cellular processes leading to hyperfusion that attenuates VZV infection. Overall design: Biological duplicates from 3 time points (12, 24 and 36 hours post infection) of uninfected MeWo cells or MeWo cells infected with varicella-zoster virus strain pOka or mutants gB[Y881F], gB[Y920F] or gB[Y881/920F]
Dysregulated Glycoprotein B-Mediated Cell-Cell Fusion Disrupts Varicella-Zoster Virus and Host Gene Transcription during Infection.
Cell line, Subject, Time
View SamplesThe mammalian suprachiasmatic nucleus (SCN) drives daily rhythmic behavior and physiology, yet a detailed understanding of its coordinated transcriptional programmes is lacking. To reveal the true nature of circadian variation in the mammalian SCN transcriptome we combined laser-capture microdissection (LCM) and RNA-Seq over a 24-hour light / dark cycle. We show that 7-times more genes exhibited a classic sinusoidal expression signature than previously observed in the SCN. Another group of 766 genes unexpectedly peaked twice, near both the start and end of the dark phase; this twin-peaking group is significantly enriched for synaptic transmission genes that are crucial for light-induced phase-shifting of the circadian clock. 342 intergenic non-coding RNAs, together with novel exons of annotated protein-coding genes, including Cry1, also show specific circadian expression variation. Overall, our data provide an important chronobiological resource (www.wgpembroke.com/shiny/SCNseq/) and allow us to propose that transcriptional timing in the SCN is gating clock resetting mechanisms. Overall design: Pooled dissected tissue of the suprachiasmatic nucleus from five adult male mice provided one of three replicates for each of six timepoints over a 12:12 light/dark (LD) cycle (ZT2, 6, 10, 14, 18 and 22). Each biological replicate was sequenced over 3 seperate lanes using Illumina HiSeq.
Temporal transcriptomics suggest that twin-peaking genes reset the clock.
Specimen part, Cell line, Subject
View SamplesInfluenza A viruses generate annual epidemics and occasional pandemics of respiratory disease with important consequences for human health and economy. Therefore, a large effort has been devoted to the development of new anti-influenza drugs directed to viral targets, as well as to the identification of cellular targets amenable for anti-influenza therapy. Here we describe a new approach to identify such potential cellular targets by screening collections of drugs approved for human use. We reasoned that this would most probably ensure addressing a cellular target and, if successful, the compound would have a well known pharmacological profile. In addition, we reasoned that a screening using a GFP-based recombinant replicon system would address virus trancription/replication and/or gene expression, and hence address a stage in virus infection more useful for inhibition. By using such strategy we identified Montelukast as an inhibitor of virus gene expression, which reduced virus multiplication in virus-infected cells but did not alter virus RNA synthesis in vitro or viral RNA accumulation in vivo. By deep sequencing of RNA isolated from mock- and virus-infected human cells, treated or not with Montelukast, we identified the PERK-mediated unfolded protein response as the pathway responsible for Montelukast action. Accordingly, PERK phosphorylation was inhibited in infected cells but stimulated in Montelukast-treated cells. These results suggest the PERK-mediated unfolded protein response as a potential cellular target to modulate influenza virus infection. Overall design: Comparison of gene expression measured by deep sequencing (single-ends, 50nt, RNA-seq) of "Infected", "Not infected", "Infected+Montelukast" and "Not infect+Montelukast" in human A549 cells. Infected means "Infected with influenza virus".
Chemical Genomics Identifies the PERK-Mediated Unfolded Protein Stress Response as a Cellular Target for Influenza Virus Inhibition.
No sample metadata fields
View SamplesHeat stress is one of the most prominent and deleterious environmental threads affecting plant growth and development. Upon high temperatures, plants launch specialized gene expression programs that promote stress protection and survival. These programs involve global and specific changes at the transcriptional and translational levels. However the coordination of these processes and their specific role in the establishment of the heat stress response is not fully elucidated.
Analysis of genome-wide changes in the translatome of Arabidopsis seedlings subjected to heat stress.
Specimen part
View SamplesWe have undertaken a screen of mouse limb tendon cells in order to identify molecular pathways involved in tendon development. Mouse limb tendon cells were isolated based on Scleraxis (Scx) expression at different stages of development: E11.5, E12.5 and E14.5
Transcriptomic analysis of mouse limb tendon cells during development.
No sample metadata fields
View SamplesWe used microarrays to determine the expression profile of the P. aeruginosa creBC mutant regarding its parental wild type strain PAO1.
The Pseudomonas aeruginosa CreBC two-component system plays a major role in the response to β-lactams, fitness, biofilm growth, and global regulation.
Treatment
View SamplesInnate immune response is the first line of antiviral defense resulting, in most cases, in pathogen clearance with minimal clinical consequences. Viruses have developed diverse strategies to evade innate immune response and to ensure their survival. Using transmissible gastroenteritis virus (TGEV) as a model, we previously reported that accessory gene 7 counteracts host antiviral response by its association with the catalytic subunit of protein phosphatase 1 (PP1c). A transcriptomic analysis was performed to further investigate the effect of gene 7 absence on the host cell.
Alphacoronavirus protein 7 modulates host innate immune response.
Specimen part, Cell line, Time
View Samples