The transcriptome and genome-wide mapping of Hif1α binding sites in kidney tubule cells
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ABSTRACT: To understand the transcription regulation of HIF1α in kidney tubule cells, we stabilized HIF1α with 50μM FG-4592 in HK2 cells. We captured ChIPseq of HIF1α and constructed transcription profile under FG-4592.
Project description:We sequenced mRNAs from glomeruli and 14 different rat renal tubule segments collected by hand microdissection. Collagenase-digested rat renal tubule segments were collected by hand microdissection. Poly(A)-mRNAs were captured from cell lysate and sequenced using paired-end protocol.
Project description:Clear cell renal cell carcinoma (ccRCC), the most common type of renal cancer is often associated with inactivation of the tumor suppressor gene von-Hippel Lindau (VHL), leading to stable expression of hypoxia inducible factors, HIF1α and HIF2α. Although HIF1α functions as a tumor suppressor gene, majority of ccRCCs constitutively express HIF1α, stratifying VHL-deficient ccRCCs into groups which express either both HIF1α and HIF2α (H1H2) or HIF2α exclusively (H2). MicroRNA (miRNA) profiling performed in these two ccRCC subtypes to identify novel molecular mechanisms. ccRCCs were classified into H1H2 and H2 subtypes by immunohostochemical staining of H1F1α and H1F2α expression. Five H1H2 tumor samples and eight H2 tumor samples were used for the study. Matched adjacent normal renal tissues were used as respective controls.
Project description:To understand the transcription regulation in kidney tubule cells, we captured histone modifications by ChIP and chromatin interaction profile by HiChIP with H3K27ac. We establish a transcription network by integrating the epigenetic map and transcription output.
Project description:LncRNA Hypoxia-inducible factor 1α-antisense 1 (HIF1α-AS1) is located on the antisense strand of the important Hypoxia-inducible factor 1α (HIF1α) gene, but being transcribed in antisense direction along the HIF1α promoter. Here we used the 3’end biotinylated HIF1a-AS1 RNA and a control RNA for RNA Pulldown and searched for interacting proteins in nuclear extracts of human umbilical vein endothelial cells (HUVEC).
Project description:Aims: Congenital heart defect (CHD) account for 25% of all human congenital abnormalities. Very few CHD-causing genes have been identified so far; so, to discover further genes we performed a global transcriptome analysis in mouse models of CHD. Methods and results: By the use of a retinoic acid competitive antagonist (BMS-189453) we caused CHD, thymic abnormalities and neural tube defects in mouse newborns. Transposition of great arteries was the prevalent cardiac defect observed (61%). Recently we were able to partially rescue this abnormal phenotype by oral administration of folic acid. Now we have performed a microarray analysis in mouse embryos (8.5 dpc) treated with BMS-189453 alone and with BMS-189453 plus folic acid (FA). On the basis of microarray and QRT-PCR results, we deeper analysed Hif1α because of its down-regulation in BMS-treated embryos vs WT and its increased expression level in BMS+FA treated embryos compared to BMS-treated ones. Immunofluorescence experiments confirmed the under-expression of Hif1α protein in BMS-treated embryos compared to WT and BMS+FA treated ones and moreover demonstrated that at 8.5 dpc Hif1α is mainly expressed in the embryo’s heart. Conclusion: We propose that Hif1α down-regulation by blocking retinoic acid binding, may contribute to the development of the cardiac defects of mouse newborns. In line with our hypothesis, when Hif1α expression level is restored (by supplementation of folic acid) a decrement of CHD is found. At the best of our knowledge this is the first report that link retinoic acid metabolism to Hif1α regulation and the development of TGA 2 samples w/ 2 dye-swaps
Project description:Published molecular profiling studies in patients with lymphoma suggested the influence of hypoxia inducible factor-1 alpha (HIF1α) targets in prognosis of DLBCL. Yet, the role of hypoxia in hematological malignancies remains unclear. We observed that activation of HIF1α resulted in global translation repression during hypoxic stress in DLBCL. Protein translation efficiency as measured using 35S-labeled methionine incorporation revealed a ≥50% reduction in translation upon activation of HIF1α. Importantly, translation was not completely inhibited and expression of clinically correlated hypoxia targets such as GLUT1, HK2, and CYT-C was found to be refractory to translational repression under hypoxia in DLBCL cells. Notably, hypoxic induction of these genes was not observed in normal primary B-cells. Translational repression was coupled with a decrease in mitochondrial function. Screening of primary DLBCL patient samples revealed that expression of HK2, which encodes for the enzyme hexokinase 2, was significantly correlated with DLBCL phenotype. Genetic knockdown studies demonstrated that HK2 is required for promoting growth of DLBCL under hypoxic stress. Altogether, our findings provide strong support for the direct contribution of HK2 in B-cell lymphoma development and suggest that HK2 is a key metabolic driver of the DLBCL phenotype.ne incorporation revealed a ≥50% reduction in translation upon activation of HIF1α. Importantly, translation was not completely blunted and expression of clinically correlated hypoxia targets such as GLUT1, HK2, and CYT-C was found to be refractory to translational repression under hypoxia in DLBCL cells. Notably, hypoxic induction of these genes was not observed in normal primary B-cells. Translational repression was coupled with decrease in mitochondrial function. Screening of DLBCL patient samples identified that expression of HK2, which encodes for the enzyme hexokinase 2, was significantly correlated with DLBCL phenotype. Genetic knockdown studies show that HK2 is required for promoting growth of DLBCL under hypoxic stress. Altogether, our findings provide more definitive proof of direct contribution of HK2 in development of B-cell lymphoma and suggest that HK2 is a key metabolic driver of DLBCL phenotype.
Project description:Clear cell renal cell carcinoma (ccRCC), the most common type of renal cancer is often associated with inactivation of the tumor suppressor gene von-Hippel Lindau (VHL), leading to stable expression of hypoxia inducible factors, HIF1α and HIF2α. Although HIF1α functions as a tumor suppressor gene, majority of ccRCCs constitutively express HIF1α, stratifying VHL-deficient ccRCCs into groups which express either both HIF1α and HIF2α (H1H2) or HIF2α exclusively (H2). MicroRNA (miRNA) profiling performed in these two ccRCC subtypes to identify novel molecular mechanisms.
Project description:Freshly isolated rat kidney proximal tubules were subjected for transcript profiling. Three microarray experiments were done to obtain the kidney proxmial tubule transcriptome.
Project description:Global gene expression in the primary cultured mouse kidney proximal tubule cells treated either DMSO or 1uM GW4064 (a FXR agonist) was compared. Results provide insight into mechanisms underlying effects of FXR activation on gene expression in mouse kidney proximal tubule cells. Male C57/BJ mice aged 6 weeks were sacrificed under anesthesia and kidney proximal tubule cells were cultured until confluent. Cells were treated with either GW4064 (1uM) or equal amount of DMSO and incubated for 24 hours. 4 total RNA samples per group were analyzed and gene expression was compared between the groups.