Hepatocyte nuclear factor-4 (HNF4, NR2A1) is a nuclear receptor which has a critical role in hepatocyte differentiation and the maintenance of homeostasis in the adult liver. However, a detailed understanding of native HNF4 in the steady state remains to be elucidated. Here we report the native HNF4 isoforms, phosphorylation status and complexes in the steady state, as shown by shotgun proteomics in HepG2 hepatocarcinoma cells. Shotgun proteomic analysis revealed the complexity of native HNF4, including multiple phosphorylation sites and inter-isoform heterodimerization. The associating complexes identified by label-free semi-quantitative proteomic analysis include the following: the DNA-dependent protein kinase catalytic subunit, histone acetyltransferase complexes, mRNA splicing complex, other nuclear receptor coactivator complexes, the chromatin remodeling complex, and the nucleosome remodeling and histone deacetylation complex. Among the associating proteins, GRB10 interacting GYF protein 2 (GIGYF2, PERQ2) is a new candidate cofactor in metabolic regulation. Moreover, an unexpected heterodimerization of HNF4 and Hepatocyte nuclear factor-4 was found. A biochemical and genome-wide analysis of transcriptional regulation showed that this heterodimerization activates gene transcription. The genes thus transcribed include the cell death-inducing DEF45-like effector b (CIDEB) gene, which is an important regulator of lipid metabolism in the liver. This suggests that the analysis of the distinctive stoichiometric balance of native HNF4 and its cofactor complexes described here is important for an accurate understanding of transcriptional regulation.
Proteomic analysis of native hepatocyte nuclear factor-4α (HNF4α) isoforms, phosphorylation status, and interactive cofactors.
Specimen part, Cell line
View SamplesHepatocyte nuclear factor-4 (HNF4, NR2A1) is a nuclear receptor which has a critical role in hepatocyte differentiation and the maintenance of homeostasis in the adult liver. However, a detailed understanding of native HNF4 in the steady state remains to be elucidated. Here we report the native HNF4 isoforms, phosphorylation status and complexes in the steady state, as shown by shotgun proteomics in HepG2 hepatocarcinoma cells. Shotgun proteomic analysis revealed the complexity of native HNF4, including multiple phosphorylation sites and inter-isoform heterodimerization. The associating complexes identified by label-free semi-quantitative proteomic analysis include the following: the DNA-dependent protein kinase catalytic subunit, histone acetyltransferase complexes, mRNA splicing complex, other nuclear receptor coactivator complexes, the chromatin remodeling complex, and the nucleosome remodeling and histone deacetylation complex. Among the associating proteins, GRB10 interacting GYF protein 2 (GIGYF2, PERQ2) is a new candidate cofactor in metabolic regulation. Moreover, an unexpected heterodimerization of HNF4 and Hepatocyte nuclear factor-4 was found. A biochemical and genome-wide analysis of transcriptional regulation showed that this heterodimerization activates gene transcription. The genes thus transcribed include the cell death-inducing DEF45-like effector b (CIDEB) gene, which is an important regulator of lipid metabolism in the liver. This suggests that the analysis of the distinctive stoichiometric balance of native HNF4 and its cofactor complexes described here is important for an accurate understanding of transcriptional regulation.
Proteomic analysis of native hepatocyte nuclear factor-4α (HNF4α) isoforms, phosphorylation status, and interactive cofactors.
Specimen part, Cell line
View SamplesPlant vascular tissues are essential for the existence of land plants. Many studies have revealed the process underlying the development of vascular tissues. However, the initiation of vascular development is still a mystery. LONESOME HIGHWAY (LHW), which encodes a bHLH transcription factor, is expressed in the initial step of vascular development in roots. LHW and TMO5 LIKE1 (T5L1) interact each other and function as a heterodimer. Here, we identified specific genes downstream of LHW-T5L1 with transformed suspension culture cells in microarray experiments.
A bHLH complex activates vascular cell division via cytokinin action in root apical meristem.
Specimen part, Treatment, Time
View SamplesGlioblastomas show heterogeneous histological features. These distinct phenotypic states are thought to be associated with the presence of glioma stem cells (GSCs), which are highly tumorigenic and self-renewing sub-population of tumor cells that have different functional characteristics. To investigate gene expression including lncRNA (long non-coding RNA) in GSC, we have performed high-throughput RNA-sequencing (RNA-seq) experiment using Illumina GAIIx. Overall design: Profiles of gene expression including lncRNA in GSC were generated by RNA-seq using Illumina GAIIx.
Targeting the Notch-regulated non-coding RNA TUG1 for glioma treatment.
No sample metadata fields
View SamplesPleomorphic adenoma gene 1 (PLAG1) encodes a transcription factor involved in cancer and growth. We study the role of PLAG1 in preimplantation embryos using STRT RNA-seq of single embryos from wild type and knockout mothers (both mated with wild type studs). The lack of maternal Plag1 led to delayed mouse 2-cell stage embryo development, compensatory expression of Plag1 from the paternal allele, and dysregulation of 1,089 genes. Half of these genes displayed a pattern of delayed activation and play roles in ribosome biogenesis and protein synthesis. These mouse genes further showed a significant overlap with human EGA genes with similar ontology, and an enrichment of the PLAG1 de novo motif. We conclude that Plag1 affects EGA through retrotransposons influencing ribosomes and protein synthesis, a mechanism that might also explain its roles in cancer and growth Overall design: Single wild type and maternal Plag1 knockout embryos at MII, 2-cell and 8-cell stage development in 14-16 biologicla replicas per developmental stage and genotype.
Pleomorphic Adenoma Gene 1 Is Needed For Timely Zygotic Genome Activation and Early Embryo Development.
Subject
View SamplesFour conditions of cultured CD8+ T cells were analyzed with Affymetrix HG-U133-Plus-2.0 microarrays.
Detection of self-reactive CD8⁺ T cells with an anergic phenotype in healthy individuals.
Specimen part
View SamplesWe found that a H3K4 specific histone methyltransferase MLL1, a mammalian homologue of Drosophila trithorax, is essential for circadian transcription. MLL1 is in a complex with CLOCK:BMAL1 and contributes to their rhythmic recruitment to circadian promoters and cyclic H3K4 tri-metylation. To analyze the function of MLL1 on circadian gene regulation, we performed comparative microarray analysis of global gene expression levels in WT and MLL1-deficient MEF, at two different circadian time points (CT18 and CT30). This analysis identified several genes whose expression levels were remarkably changed between CT18 and CT30 in WT and MLL1-KO MEF. Typical clock-regulated genes such as Per2, Per3, Bmal1, or Dbp were found to be changing in WT but not in MLL1-KO MEFs.
The histone methyltransferase MLL1 permits the oscillation of circadian gene expression.
Specimen part, Time
View SamplesBackground: Breast cancer patients present lower 1,25(OH)2D3 or 25(OH)D3 serum levels than unaffected women. Although 1,25(OH)2D3 pharmacological concentrations of 1,25(OH)2D3 may exert antiproliferative effects in breast cancer cell lines, much uncertainty remains about the effects of calcitriol supplementation in tumor specimens in vivo. We have evaluated tumor dimension (ultrassonography), proliferative index (Ki67 expression), 25(OH)D3 serum concentration and gene expression profile, before and after a short term calcitriol supplementation (dose to prevent osteoporosis) to post-menopausal patients. Results: Thirty three patients with operable disease had tumor samples evaluated. Most of them (87.5%) presented 25(OH)D3 insufficiency (<30 ng/mL). Median period of calcitriol supplementation was 30 days. Although tumor dimension did not vary, Ki67 immunoexpression decreased after supplementation. Transcriptional analysis of 15 matched pre/post-supplementation samples using U133 Plus 2.0 GeneChip (Affymetrix) revealed 18 genes over-expressed in post-supplementation tumors. As a technical validation procedure, expression of four genes was also determined by RT-qPCR and a direct correlation was observed between both methods (microarray vs PCR). To further explore the effects of near physiological concentrations of calcitriol on breast cancer samples, an ex vivo model of fresh tumor slices was utilized. Tumor samples from another 12 post-menopausal patients were sliced and treated in vitro with slightly high concentrations of calcitriol (0.5nM), that can be attained in vivo, for 24 hours In this model, expression of PBEF1, EGR1, ATF3, FOS and RGS1 was not induced after a short exposure to calcitriol. Conclusions: In our work, most post-menopausal breast cancer patients presented at least 25(OH)D3 insufficiency. In these patients, a short period of calcitriol supplementation may prevent tumor growth and reduce Ki67 expression, probably associated with discrete transcriptional changes. This observation deserves further investigation to better clarify calcitriol effects in tumor behavior under physiological conditions.
Calcitriol supplementation effects on Ki67 expression and transcriptional profile of breast cancer specimens from post-menopausal patients.
Sex, Age, Specimen part
View SamplesHepatic iron overload is a risk factor for progression of hepatocellular carcinoma (HCC), although the molecular mechanisms underlying this association have remained unclear. We now show that the iron-sensing ubiquitin ligase FBXL5 is previously unrecognized oncosuppressor in liver carcinogenesis in mice. Hepatocellular iron overload evoked by FBXL5 ablation gives rise to oxidative stress, tissue damage, inflammation and compensatory proliferation in hepatocytes and to consequent promotion of liver carcinogenesis induced by exposure to a chemical carcinogen. The tumor-promoting effect of FBXL5 deficiency in the liver is also operative in a model of virus-induced HCC. FBXL5-deficient mice thus constitute the first genetically engineered mouse model of liver carcinogenesis induced by iron overload. Dysregulation of FBXL5-mediated cellular iron homeostasis was also found to be associated with poor prognosis in human HCC, implicating FBXL5 plays a significant role in defense against hepatocarcinogenesis. Overall design: Total RNA was extracted from the nontumor and tumor tissue of an Alb-Cre/Fbxl5F/F male mouse (nontumor, n = 5; tumor, n = 5) or two littermate control Fbxl5F/F mice (nontumor, n = 6; tumor, n = 6) at 45 weeks of age.
Disruption of FBXL5-mediated cellular iron homeostasis promotes liver carcinogenesis.
Specimen part, Cell line, Subject
View SamplesWe have developed a new conditional transgenic mouse showing that MLL-ENL, at an endogenous-like expression level, induces leukemic transformation selectively in LT-HSCs. To investigate the molecular mechanism of leukemic transformation in LT-HSCs conditionally expressing MLL-ENL, we preliminarily performed comprehensive gene expression profiling of CreER-transduced LT-HSCs and ST-HSCs using cDNA microarray analysis.
Plzf drives MLL-fusion-mediated leukemogenesis specifically in long-term hematopoietic stem cells.
Specimen part
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