Endothelin-1 (ET-1) plays a critical role in connective tissue remodeling by fibroblasts during tissue repair and fibrosis. We investigated the molecular pathways in the transmission of ET-1 signals that lead to features of connective tissue remodeling, in particular the role of FAK (focal adhesion kinase).
Inhibition of focal adhesion kinase prevents experimental lung fibrosis and myofibroblast formation.
Specimen part, Treatment
View SamplesCCAAT/enhancer binding protein beta (C/EBPb) is a member of a family of highly conserved transcription factors that regulates numerous genes involved in proliferation and differentiation in a variety of tissues. C/EBPb is deregulated in human breast cancer and germline deletion of this gene results in multiple defects in mammary gland development. We hypothesized that C/EBPb regulates mammary stem cell self-renewal, maintenance and/or differentiation through the regulation of multiple target genes that coordinate mammary gland development. Utilizing both a germline knockout mouse model and a conditional knockout strategy, we demonstrated that mammosphere formation was significantly decreased in C/EBPb-deficient mammary epithelial cells (MECs). The ability of C/EBPb-deleted MECs to regenerate the mammary gland in vivo was severely impaired when transplanted at limiting dilution. Furthermore, serial transplantation of C/EBPb-null mammary tissue resulted in decreased outgrowth potential when compared to wildtype, and an early senescence phenotype. Flow cytometric analysis revealed that C/EBPb-null MECs contain a lower frequency of repopulating stem cells accompanied by an increase in committed, differentiated luminal cells as compared to wildtype. Microarray analysis of stem/progenitor cell populations was performed and revealed an alteration in cell fate specification in C/EBPb-null glands, exemplified by the aberrant expression of basal markers in the luminal cell compartment. Collectively, our studies demonstrate that C/EBPb is a critical regulator of mammary stem cell differentiation, and an important determinant of luminal cell fate specification.
CCAAT/enhancer binding protein beta regulates stem cell activity and specifies luminal cell fate in the mammary gland.
Specimen part
View SamplesQuaking are RNA binding proteins, which are known to regulate the expression of different genes at the post-transcriptional level. Genetic interference with quaking a (qkia) and quaking c (qkic) leads to major myofibril defects during zebrafish development, without affecting early muscle differentiation. In order to understand how qkia and qkic jointly regulate myofibril formation, we performed a comparative analysis of the transcriptome of qkia/qkic (qkia mutant injected with qkic morpholino) versus control embryos. We show that Quaking activity is required for accumulation of the muscle-specific tropomyosin 3 transcript, tpm3.1. Whereas interference with tmp3.1 function disrupts myofibril formation, reintroducing tpm3.1 transcripts into embryos with reduced Quaking activity can restore structured myofibrils. Thus, we identify tropomyosin as an essential component in the process of myofibril formation and as a relay downstream of the regulator proteins Quaking. Overall design: Transcriptome of control versus qkia/qkic embryos at 24-26hpf. Biological triplicate were prepared for both condition (3x2 samples).
Quaking RNA-Binding Proteins Control Early Myofibril Formation by Modulating Tropomyosin.
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View SamplesThe innate immune system is a two-edged sword; it is absolutely required for host defense against infection, but if left uncontrolled can trigger a plethora of inflammatory diseases. Here we used systems biology approaches to predict and validate a gene regulatory network involving a dynamic interplay between the transcription factors NF-B, C/EBP, and ATF3 that controls inflammatory responses. We mathematically modeled transcriptional regulation of Il6 and Cebpd genes and experimentally validated the prediction that the combination of an initiator (NF-B), an amplifier (C/EBP) and an attenuator (ATF3) forms a regulatory circuit that discriminates between transient and persistent Toll-like receptor 4-induced signals. Our results suggest a mechanism that enables the innate immune system to detect the duration of infection and to respond appropriately.
Function of C/EBPdelta in a regulatory circuit that discriminates between transient and persistent TLR4-induced signals.
Sex, Specimen part
View SamplesComparison of transcriptional profile of CD8 cytotoxic T lymphocytes terated with the mTORC1 inhibitor rapamycin or the mTOR inhibitor KU-0063794 and comparison with proteomic analysis.
The cytotoxic T cell proteome and its shaping by the kinase mTOR.
Specimen part, Treatment
View SamplesAffymetrix Mouse Genome 430 2.0 arrays were used to measure genome-wide gene expression levels. The results show that high-risk human papillomavirus oncogenes E6 and E7 reprogram the cervical cancer microenvironment independently of and synergistically with estrogen, a critical co-factor in cervical cancer development and maintenance.
Human papillomavirus oncogenes reprogram the cervical cancer microenvironment independently of and synergistically with estrogen.
Specimen part, Treatment
View SamplesAlthough it has recently been shown that A/J mice are highly susceptible to Staphylococcus aureus sepsis as compared to C57BL/6J, the specific genes responsible for this differential phenotype are unknown. Using chromosome substitution strains (CSS), we found that factors on chromosomes (chr) 8, 11, and 18 are responsible for susceptibility to S. aureus sepsis in A/J mice. F1 mice from C57BL/6J X CSS8 cross (C8A) and C57BL/6J X CSS18 (C18A) were also susceptible to S. aureus (median survival < 48 h), whereas F1 mice from C57BL/6J X CSS11 cross (C11A) were resistant (median survival > 120 h) to S. aureus. Bacterial loads in the kidney were consistent with F1 median survivals, with higher bacterial counts in susceptible mice. No sexlinked associations with susceptibility were noted in F1 intercrosses. Using whole genome transcription profiling, we identified a total of 192 genes on chromosomes 8, 11, and 18 which are differentially expressed between A/J and C57BL/6J in the setting of S. aureus infection. Of these, 28 genes had Gene Ontology annotations indicating a potential immune response function. These 28 genes are associated with susceptibility to S. aureus in A/J mice, and are potential determinants of susceptibility to S. aureus infection in humans.
Two genes on A/J chromosome 18 are associated with susceptibility to Staphylococcus aureus infection by combined microarray and QTL analyses.
Time
View SamplesNarcolepsy is a sleep disorder characterized by excessive daytime sleepiness and attacks of muscle atonia triggered by strong emotions (cataplexy). The best biological marker of narcolepsy is orexin deficiency with dramatic loss in hypothalamic orexin-producing neurons. Together with a tight HLA and T-cell receptor alpha(5) association, narcolepsy is believed to be autoimmune although all attempts to prove it have failed.To characterize orexin specific peptides we produced a transgenic mouse model to access to the orexin neurons transcription profile. We generated BAC-based transgenic mice by replacing the orexin coding sequence by a flag-tagged poly(A) binding protein (Pabp1) cDNA sequence. The basis of this construct is to take advantage of the ability of Pabp1 to bind to the poly(A) tails of mRNAs in vivo. Thus mRNAs from orexin cells are expected to be enriched by cross-linking them to the flag-tagged PABP and then co-immunoprecipitating this complex with a specific anti-flag monoclonal antibody.
Elevated Tribbles homolog 2-specific antibody levels in narcolepsy patients.
Age
View SamplesTriggering of B cell receptors (BCR) induces a massive synthesis of NFATc1 in splenic B cells. By inactivating the Nfatc1 gene and re-expressing NFATc1 we show that NFATc1 levels are critical for the survival of splenic B cells upon BCR stimulation. NFATc1 ablation led to decreased BCR-induced Ca++ flux and proliferation of splenic B cells, increased apoptosis and suppressed germinal centre formation and immunoglobulin class switch by T cell-independent antigens. By controlling IL-10 synthesis in B cells, NFATc1 supported the proliferation and IL-2 synthesis of T cells in vitro and appeared to contribute to the mild clinical course of Experimental Autoimmune Encephalomyelitis in mice bearing NFATc1-/- B cells. These data indicate NFATc1 as a key factor controlling B cell function.
NFATc1 affects mouse splenic B cell function by controlling the calcineurin--NFAT signaling network.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Protein kinase c-β-dependent activation of NF-κB in stromal cells is indispensable for the survival of chronic lymphocytic leukemia B cells in vivo.
Specimen part, Cell line
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