The integrated stress response (ISR) controls cellular adaptations to nutrient deprivation, redox imbalances and ER stress. ISR genes are upregulated in stressed cells, primarily by the bZIP transcription factor ATF4 through its recruitment to cis-regulatory C/EBP:ATF response elements (CAREs) together with a dimeric partner of uncertain identity. Here we show that C/EBP:ATF4 heterodimers, but not C/EBP:ATF4 dimers, are the predominant CARE binding species in stressed cells. C/EBP and ATF4 associate with genomic CAREs in a mutually-dependent manner and co-regulate many ISR genes. By contrast, the C/EBP family members C/EBP and CHOP were largely dispensable for induction of stress genes. Cebpg/ MEFs proliferate poorly and exhibit oxidative stress due to reduced glutathione levels and impaired expression of several glutathione biosynthesis pathway genes. Cebpg/ mice (C57BL/6 background) display reduced body size and microphthalmia, similar to ATF4-null animals. In addition, C/EBP-deficient newborns die from atelectasis and respiratory failure which can be mitigated by in utero exposure to the anti-oxidant, N-acetyl-cysteine. Cebpg/ mice on a mixed strain background show improved viability but, upon aging, develop significantly fewer malignant solid tumors compared to WT animals. Our findings identify C/EBP as a novel anti-oxidant regulator and an obligatory ATF4 partner that controls redox homeostasis in normal and cancerous cells.
C/EBPγ Is a Critical Regulator of Cellular Stress Response Networks through Heterodimerization with ATF4.
Specimen part
View SamplesPharmaceutical chemicals used in human medicine are released into surface waters via municipal effluents and pose a risk for aquatic organisms. Among these substances are selective serotonin reuptake inhibitors (SSRIs) which can affect aquatic organisms at sub ppb concentrations. To better understand biochemical pathways influenced by SSRIs, evaluate changes in the transcriptome, and identify gene transcripts with potential for biomarkers of exposure to SSRIs; larval zebrafish Danio rerio were exposed (96 h) to two concentrations (25 and 250 g/L) of the SSRIs, fluoxetine and sertraline, and changes in global gene expression were evaluated (Affymetrix GeneChip Zebrafish Array). Significant changes in gene expression (>=1.7 fold change, p<0.05) were determined with Partek Genomics Suite Gene Expression Data Analysis System and ontology analysis was conducted using Molecular Annotation System 3. The number of genes differentially expressed after fluoxetine exposure was 288 at 25 g/L and 131 at 250 g/L; and after sertraline exposure was 33 at 25 g/L and 52 at 250 g/L. Five genes were differentially regulated in all treatments relative to control, suggesting that both SSRIs share some similar molecular pathways. Among them, expression of the gene coding for FK506 binding protein 5 (FKBP5), which is annotated to stress response regulation, was highly down-regulated in all treatments (results confirmed by qRT-PCR). Gene ontology analysis indicated that regulation of stress response and cholinesterase activity were critical functions influenced by these SSRIs, and suggested that changes in the transcription of FKBP5 or acetylcholinesterase could be useful biomarkers of SSRIs exposure in wild fish.
Global gene expression in larval zebrafish (Danio rerio) exposed to selective serotonin reuptake inhibitors (fluoxetine and sertraline) reveals unique expression profiles and potential biomarkers of exposure.
No sample metadata fields
View SamplesCancer-associated fibroblasts (CAFs) have been reported to support tumor progression by a variety of mechanisms. However, their role in the progression of non-small cell lung cancer (NSCLC) remains poorly defined. In addition, the extent to which specific proteins secreted by CAFs contribute directly to tumor growth is unclear. To study the role of CAFs in NSCLC, a cross-species functional characterization of mouse and human lung CAFs was performed, including gene expression analysis comparing normal mouse lung fibroblasts (NFs) and mouse lung CAFs to seek for differentially-expressed secreted proteins.
Cross-species functional analysis of cancer-associated fibroblasts identifies a critical role for CLCF1 and IL-6 in non-small cell lung cancer in vivo.
Specimen part
View SamplesGlud1 (Glutamate dehydrogenase 1) transgenic mice release more excitatory neurotransmitter glutamate to synaptic cleft throughout lifespan.
Gene expression patterns in the hippocampus during the development and aging of Glud1 (Glutamate Dehydrogenase 1) transgenic and wild type mice.
Specimen part
View SamplesZebrafish (Danio rerio) were obtained from the Zebrafish Research Facility maintained in the Center for Environmental Biotechnology at the University of Tennessee. Fish husbandry, spawning, and experimental procedures were conducted with approval from the University of Tennessee Institutional Animal Care and Use Committee (Protocol #1690-1007). Water for holding fish and conducting experiments (hereafter referred to as fish water) consisted of MilliQ water (Millipore, Bedford, MA) with ions added: 19 mg/L NaHCO3, 1 mg/L sea salt (Instant Ocean Synthetic Sea Salt, Mentor, OH), 10 mg/L CaSO4, 10 mg/L MgSO4, 2 mg/L KCl. Embryos were obtained by spawning adult fish with no history of contaminant exposure. Fertilization of embryos took place at the same time ( 15 min.), such that larvae used in experiments were of similar age at the time of exposure. All activities (maintenance of adult fish, spawning, and experiments) were conducted in an environmental chamber with a temperature of 27 1 C and 14:10h light:dark photoperiod.
Global gene expression profiling in larval zebrafish exposed to microcystin-LR and microcystis reveals endocrine disrupting effects of Cyanobacteria.
No sample metadata fields
View SamplesTo uncover the gene expression alterations that occur during lung cancer progression, we interrogated the gene expression state of neoplastic cells at different stages of malignant progression. We initiated tumors in KrasLSL-G12D/+;p53flox/flox;R26LSL-tdTomato (KPT) mice with a pool of barcoded lentiviral-Cre vectors and purified Tomatopositive cancer cells away from the diverse and variable stromal cell populations. Five to nine months after tumor initiation, cancer cells were isolated from individual primary tumors and metastases using fluorescence-activated cell sorting. Sequencing of the barcode region of the integrated lentiviral vectors established primary tumor-metastasis and metastasis-metastasis relationships. Tumor barcoding allowed us to unequivocally distinguish non-metastatic primary tumors (TnonMet) from those primary tumors that had seeded metastases (TMet). We profiled 10 TnonMet samples as well as TMet and metastasis (Met) samples representing 12 metastatic events. To examine additional earlier stages of lung cancer development, we also analyzed premalignant cells from hyperplasias that develop in KPT mice shortly after tumor initiation (KPT-Early; KPT-E), as well as tumors from KrasG12D;R26LSL-tdTomato (KT) mice which rarely gain metastatic ability Overall design: This study includes 52 samples: 3 KP late samples, 3KPT early samples,10 non-metastatic primary tumors, 9 metastatic primary tumors, and 27 metastasis in different organs. total RNA was isolated and prepared for sequencing using the Ovation® RNA-Seq system and Illumina TruSeq DNA kit (v2) to generate 100bp paired end reads. Reads were aligned to mm10.
Molecular definition of a metastatic lung cancer state reveals a targetable CD109-Janus kinase-Stat axis.
Subject
View SamplesMesenchyme-derived cells in the human airway wall including airway smooth muscle cells, fibroblasts and myofibroblasts are known to play important roles in airway remodeling. The lack of specific phenotypic markers makes it difficult to define these cell populations in primary cultures. The objectives of this study were to evaluate reported markers and to identify novel markers to define these cell types.
Can lineage-specific markers be identified to characterize mesenchyme-derived cell populations in the human airways?
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
High-throughput screening of tyrosine kinase inhibitor cardiotoxicity with human induced pluripotent stem cells.
Specimen part, Cell line, Treatment, Subject
View SamplesTyrosine kinase inhibitors (TKIs), despite efficacy as anti-cancer therapies, are associated with cardiovascular side effects ranging from induced arrhythmias to heart failure. We have utilized patient-specific human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), generated from 11 healthy individuals and 2 patients receiving cancer treatment, to screen FDA-approved TKIs for cardiotoxicities by measuring alterations in cardiomyocyte viability, contractility, electrophysiology, calcium handling, and signaling. With these data, we generated a cardiac safety index to assess cardiotoxicities of existing TKIs. Many TKIs with a low cardiac safety index exhibit cardiotoxicity in patients. We also derived endothelial cells (hiPSC-ECs) and cardiac fibroblasts (hiPSC-CFs) to examine cell type-specific cardiotoxicities. Using high-throughput screening, we determined that VEGFR2/PDGFR-inhibiting TKIs caused cardiotoxicity in hiPSC-CMs, hiPSC-ECs, and hiPSC-CFs. Using phosphoprotein analysis, we determined that VEGFR2/PDGFR-inhibiting TKIs led to a compensatory increase in cardioprotective insulin and insulin-like growth factor (IGF) signaling in hiPSC-CMs. Activating cardioprotective signaling with exogenous insulin or IGF1 improved hiPSC-CM viability during co-treatment with cardiotoxic VEGFR2/PDGFR-inhibiting TKIs. Thus, hiPSC-CMs can be used to screen for cardiovascular toxicities associated with anti-cancer TKIs, correlating with clinical phenotypes. This approach provides unexpected insights, as illustrated by our finding that toxicity can be alleviated via cardioprotective insulin/IGF signaling.
High-throughput screening of tyrosine kinase inhibitor cardiotoxicity with human induced pluripotent stem cells.
Treatment, Subject
View SamplesTranslating ribosome affinity purification technology was used to isolate mRNAs from cerebellar Purkinje neurons from control (Pcp2-BacTrap; Rbm17 f/+) and mutant (Pcp2-BacTRAP; Pcp2-Cre; Rbm17 f/-) mice. Overall design: RNA isolation was performed when animals were four-weeks-old (n=3 animals per genotype). Using NuGEN Ovation RNA-Seq System v2, purified double-stranded cDNA was generated from 10 ng of total RNA and amplified using both 3' poly (A) selection and random priming. 2 µg of each sample was sheared using the Covaris S2 focused-ultrasonicator following the manufacturer's protocol to obtain a final library with insert size of 400 bp. The sheared samples were quantified using the NanoDrop ND-1000 spectrophotometer and Invitrogen Qubit 2.0 DNA quantitation assay. The fragment sizes were confirmed on the Agilent Bioanalyzer to verify proper shearing. A double-stranded DNA library was produced using Illumina TruSeq DNA library preparation system and the sequencing was run on a HiSeq 2500 system.
Extensive cryptic splicing upon loss of RBM17 and TDP43 in neurodegeneration models.
Specimen part, Cell line, Subject
View Samples