Project description:In order to identify the effects of JNK inhibitor or p38 Inhibitor on the transcriptome of ATP7B H1069Q-overexpressing liver cells, we performed RNAseq experiments
Project description:In order to identify the effects of ATP7B H1069Q overexpression on the liver transcriptome, we performed Affymetrix GeneChip hybridization experiments. Transcriptome analysis of the hepatocytes overexpressing ATP7B H1069Q, compared with hepatocytes overexpressing ATP7B WT. For the analysis on the hepatocytes overexpressing ATP7B H1069Q, total RNA was extracted from HepG2 cells; RNA extracted from hepatocytes overexpressing ATP7B WT was used as control.
Project description:Bis-2-chloroethyl sulfide (sulfur mustard, SM) is a potent alkylating agent and vesicant. Exposure to SM results in activation of numerous signaling cascades, including mitogen-activated protein kinase (MAPK) signaling pathways. These pathways include the Erk, p38, and JNK pathways, which are involved in cell growth, inflammation, and stress signaling. However, the precise roles of these pathways in SM toxicity have not been fully elucidated. We used Western blotting and microarray analysis to examine the activation and role of each pathway following SM exposure in primary human epidermal keratinocytes. Western blotting revealed increased phosphorylation of p38 and JNK following SM exposure; however, phosphorylation of Erk was equivocal, suggesting that growth conditions may impact activation of Erk by SM. We used pharmacologic inhibitors to target each MAPK and then compared the gene expression profiles to identify SM-induced gene networks regulated by each MAPK. Cells were pretreated with 10 µM SB 203580 (p38 inhibitor), PD 98059 (Erk inhibitor), or SP 600125 (JNK inhibitor) 60 minutes before exposure to 200 µM SM. Cells were harvested at 1h, 4h, and 8h post-exposure, and RNA was extracted for synthesis of microarray probes. Probes were hybridized to Affymetrix U133 Plus 2.0 arrays for gene expression profiling. Analysis of variance was performed to identify genes significantly modulated due to pharmacologic inhibition in SM-exposed cells. Pathway mapping confirmed alterations in SM-induced Erk, JNK, and p38 MAPK signaling due to pharmacologic inhibition. SM-induced expression of IL-8, IL-6, and TNF-alpha was decreased by p38 MAPK inhibition, but not by inhibition of other MAPKs. Based on the number of significant pathways mapped to each MAPK in the presence and absence of inhibitors, the p38 MAPK pathway appeared to be the MAPK pathway most responsive to SM exposure. Interestingly, pathway mapping of the microarray data identified potential cross-talk between MAPK signaling pathways and other pathways involved in SM-induced signaling. Mining of these results will increase our understanding of the role of MAPK pathways in SM-induced signal transduction and may identify potential therapeutic targets for medical countermeasure development.
Project description:To understand whether hepatic cells use autophagy to defend against Cu toxicity in WD, we employed ATP7B knockout (ATP7B-KO) HepG2 cell line, by Quant-seq experiments. Transcriptome analysis of the of ATP7B KO cells and WT cells treated with Copper (Cu) compared with untreated cells.
Project description:Epidermal keratinocytes respond to extracellular influences by activating cytoplasmic signal transduction pathways that change the transcriptional profiles of affected cells. To define responses to two such pathways, p38 and ERK, we used SB203580 and PD98059 as specific inhibitors, and identified the regulated genes after 1, 4, 24 and 48 hrs, using Affymetrix’ Hu133Av2 microarrays. Additionally, we compared genes specifically regulated by p38 and ERKs with those regulated by JNK and by all three pathways simultaneously. We find that the p38 pathway induces the expression of extracellular matrix and proliferation-associated genes, while suppressing microtubule-associated genes; the ERK pathway induces the expression of nuclear envelope and mRNA splicing proteins, while suppressing steroid synthesis and mitochondrial energy production enzymes. Both pathways promote epidermal differentiation and induce feedback inactivation of MAPK signaling. c-FOS, SRY and N-Myc appear to be the principal targets of the p38 pathway, Elk-1 SAP1 and HLH2 of ERK, while FREAC-4, ARNT and USF are common to both. The results for the first time comprehensively define the genes regulated by the p38 and ERK pathways in epidermal keratinocytes and suggest a list of targets potentially useful in therapeutic interventions. Human epidermal keratinocytes are grown in Keratinocyte Serum-Free Medium (Gibco) supplemented with 0.05 mg/ml bovine pituitary extract, 2.5 ng/ml epidermal growth factor, 0.09 mM CalCl2 and 1% penicillin/streptomycin (KGM). They are switched to Keratinocyte Serum Free-Media (Gibco) supplemented only with 1% penicillin/streptomycin (KBM) 24 h prior to commencing experiments. A set is left as controls, others treated with 5 uM JNK inhibitor SP600125, 15 uM p38 inhibitor SB203580, or 50 um ERK inhibitor PD98059. Timecourse of treated and parellel control samples over a 48 hr period was performed.
Project description:In order to identify the effects of ATP7B H1069Q overexpression on the liver transcriptome, we performed Affymetrix GeneChip hybridization experiments. Transcriptome analysis of the hepatocytes overexpressing ATP7B H1069Q, compared with hepatocytes overexpressing ATP7B WT.
Project description:The mitogen-activated protein kinase (MAPK) p38alpha controls inflammatory responses and cell proliferation. Using mice carrying conditional p38alpha alleles, we investigated its function in postnatal development and tumorigenesis. When p38alpha is specifically deleted in the mouse embryo, fetuses develop to term but die shortly after birth, likely due to lung dysfunction. Fetal hematopoietic cells and embryonic fibroblasts deficient in p38alpha display increased proliferation, resulting from sustained activation of the c-Jun N-terminal kinase (JNK)/c-Jun pathway. Importantly, in chemical-induced liver cancer development, mice with liver-specific deletion of p38alpha show enhanced hepatocyte proliferation and tumor development that also correlates with JNK/c-Jun upregulation. Furthermore, increased proliferation of p38alpha-deficient hepatocytes and tumor cells is suppressed by inactivation of JNK or c-Jun. These results reveal a novel mechanism whereby p38alpha negatively regulates cell proliferation through antagonizing the JNK/c-Jun pathway in multiple cell types and in liver cancer development. We used microarrays to identifiy differental regulated genes by p38alpha in fetal liver cells Experiment Overall Design: Wild type and p38 deficient fetal liver cell were used for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Purpose:Wilson's disease (WD) is a rare hereditary disorder due to ATP7B gene mutation, causing pathologic copper storage mainly in the liver and neurological systems. Hepatocyte transplantation showed therapeutic potential, however, this strategy is often hindered by a shortage of quality donor cells and by allogeneic immune rejection. Here we evaluate the function and efficacy of autologous reprogrammed, ATP7B gene-restored hepatocytes using a murine model of WD Mathods and Results: By reprogramming hepatocytes from ATP7B-/- mice with small molecules, sufficient liver progenitor cells (LPCs) are harvested. After lentivirus-mediated miniATP7B gene transfection and re-differentiation, functional LPC-ATP7B-Heps are developed. RNA-seq data show that compared with LPC-GFP-Heps with enrichment of genes mainly in pathways of oxidative stress and cell apoptosis, in LPC-ATP7B-Heps under high copper stress pathways for copper ion binding and cell proliferation are enriched. LPC-ATP7B-Heps transplantation into ATP7B-/- mice alleviates deposition of excess liver copper with its associated inflammation and fibrosis, comparable to those observed using normal primary hepatocytes at four months after transplantation. Conclusion: We establish the autologous reprogrammed, ATP7B gene restored LPC-ATP7B-Heps and further transplantation demonstrate alleviated copper accumulation in WD mice.
Project description:p38 and JNK are activated in response to acute stress and inflammatory signals. Through modification of a plethora of substrates, these kinases profoundly re-shape cellular physiology for the optimal response to a harmful environment and/or an inflammatory state. Here, we utilized phospho-proteomics to identify several hundred substrates for both kinases. Our results indicate that the scale of signaling from p38 and JNK are of a similar magnitude. Among the many new targets, we highlight the regulation of the transcriptional regulators GIGYF1 and 2 by p38-dependent MK2 phosphorylation and 14-3-3 binding. We also show that the Golgi apparatus contains numerous substrates, and is a major target for regulation by p38 and JNK. When activated, these kinases mediate structural rearrangement of the Golgi apparatus which positively affects protein flux through the secretory system. Our work expands on our knowledge about p38 and JNK signaling with important biological ramifications.