Project description:Analysis of gene expression in human embryonic kidney cells HEK293 overexpressing the transcription factors HNF4a2 or mutant forms HNF4a2 C106R and HNF4a2 R154X, which were introduced by FRT/FLP recombination. The analysis was performed 24 hours following 1µg/ml tetracycline treatment to induce the expression of the genes. Results identify HNF4a regulated genes in kidney cells being several of these genes deregulated in renal cell carcinoma. Keywords = HEK293 embryonic kidney cells Keywords = HNF4a2 Keywords = tetracycline Keywords = FRT Keywords: ordered
Project description:Hepatocyte nuclear factor 1beta (HNF1beta, TCF2) is a tissue-specific transcription factor whose mutation in humans leads to renal cysts, genital malformations, pancreas atrophy and maturity onset diabetes of the young (MODY5). Furthermore, HNF1beta overexpression has been observed in clear cell cancer of the ovary. To identify potential HNF1beta target genes whose activity may be deregulated in human patients we established a human embryonic kidney cell line (HEK293) expressing HNF1beta conditionally. Using Flp recombinase we introduced wildtype or mutated HNF1beta at a defined chromosomal position allowing a most reproducible induction of the HNF1beta derivatives upon tetracycline addition. By oligonucleotide microarrays we identified 25 HNF1beta regulated genes. By an identical approach we identified that the closely related transcription factor HNF1alpha (TCF1) affects only nine genes in HEK293 cells and thus is a less efficient factor in these kidney cells. The HNF1beta target genes dipeptidyl peptidase 4 (DPP4), angiotensin converting enzyme 2 (ACE2) and osteopontin (SPP1) are most likely direct target genes, as they contain functional HNF1 binding sites in their promoter region. Since nine of the potential HNF1beta target genes are deregulated in clear cell carcinoma of the ovary, we propose that HNF1beta overexpression in the ovarian cancer participates in the altered expression pattern Experiment Overall Design: Two different clones (biological replicates) were analyzed per transcription factor or mutant. By tetracyclin addition the expression of the transcription factors was induced for 24 hours prior to RNA extraction and array analysis.
Project description:Chavez2009 - a core regulatory network of OCT4 in human embryonic stem cells
A core OCT4-regulated network has been identified as a test case, to analyase stem cell characteristics and cellular differentiation.
This model is described in the article:
In silico identification of a core regulatory network of OCT4 in human embryonic stem cells using an integrated approach.
Chavez L, Bais AS, Vingron M, Lehrach H, Adjaye J, Herwig R
BMC Genomics, 2009, 10:314
Abstract:
BACKGROUND: The transcription factor OCT4 is highly expressed in pluripotent embryonic stem cells which are derived from the inner cell mass of mammalian blastocysts. Pluripotency and self renewal are controlled by a transcription regulatory network governed by the transcription factors OCT4, SOX2 and NANOG. Recent studies on reprogramming somatic cells to induced pluripotent stem cells highlight OCT4 as a key regulator of pluripotency.
RESULTS: We have carried out an integrated analysis of high-throughput data (ChIP-on-chip and RNAi experiments along with promoter sequence analysis of putative target genes) and identified a core OCT4 regulatory network in human embryonic stem cells consisting of 33 target genes. Enrichment analysis with these target genes revealed that this integrative analysis increases the functional information content by factors of 1.3 - 4.7 compared to the individual studies. In order to identify potential regulatory co-factors of OCT4, we performed a de novo motif analysis. In addition to known validated OCT4 motifs we obtained binding sites similar to motifs recognized by further regulators of pluripotency and development; e.g. the heterodimer of the transcription factors C-MYC and MAX, a prerequisite for C-MYC transcriptional activity that leads to cell growth and proliferation.
CONCLUSION: Our analysis shows how heterogeneous functional information can be integrated in order to reconstruct gene regulatory networks. As a test case we identified a core OCT4-regulated network that is important for the analysis of stem cell characteristics and cellular differentiation. Functional information is largely enriched using different experimental results. The de novo motif discovery identified well-known regulators closely connected to the OCT4 network as well as potential new regulators of pluripotency and differentiation. These results provide the basis for further targeted functional studies.
This model is hosted on BioModels Database
and identified
by: MODEL1305010000
.
To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource
for published quantitative kinetic models
.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to the public
domain worldwide. Please refer to CC0 Public Domain
Dedication
for more information.
Project description:Transcriptional profiling of human embryo kidney cells comparing control HEK293 transfected with empty vectors cells with HEK293 cells transfected with pcDNA3-ZNF191 (or ZNF191 siRNA vector). We searched for early ZNF191 target genes by using a transient overexpression and knockdown strategy in the human embryo kidney (HEK293) cells. A table of gene targets of transcription factor ZNF191 commonly identified by both strategies is appended below as a supplementary file.
Project description:Analysis of gene expression in human embryonic kidney cells HEK293 overexpressing the transcription factors HNF4a2 or mutant forms HNF4a2 C106R and HNF4a2 R154X, which were introduced by FRT/FLP recombination. The analysis was performed 24 hours following 1sg/ml tetracycline treatment to induce the expression of the genes. Results identify HNF4a regulated genes in kidney cells being several of these genes deregulated in renal cell carcinoma.<br><br>Note that files GSM52180.txt and GSM52184.txt as downloaded from GEO are identical.
Project description:Hepatocyte nuclear factor 1beta (HNF1beta, TCF2) is a tissue-specific transcription factor whose mutation in humans leads to renal cysts, genital malformations, pancreas atrophy and maturity onset diabetes of the young (MODY5). Furthermore, HNF1beta overexpression has been observed in clear cell cancer of the ovary. To identify potential HNF1beta target genes whose activity may be deregulated in human patients we established a human embryonic kidney cell line (HEK293) expressing HNF1beta conditionally. Using Flp recombinase we introduced wildtype or mutated HNF1beta at a defined chromosomal position allowing a most reproducible induction of the HNF1beta derivatives upon tetracycline addition. By oligonucleotide microarrays we identified 25 HNF1beta regulated genes. By an identical approach we identified that the closely related transcription factor HNF1alpha (TCF1) affects only nine genes in HEK293 cells and thus is a less efficient factor in these kidney cells. The HNF1beta target genes dipeptidyl peptidase 4 (DPP4), angiotensin converting enzyme 2 (ACE2) and osteopontin (SPP1) are most likely direct target genes, as they contain functional HNF1 binding sites in their promoter region. Since nine of the potential HNF1beta target genes are deregulated in clear cell carcinoma of the ovary, we propose that HNF1beta overexpression in the ovarian cancer participates in the altered expression pattern Keywords: cnditional expression
Project description:We analyzed lncRNAs located in CNV loci associated with congenital anomalies of the kidney and urinary tract (CAKUT). HSALNG0134318 at CNV 22q11 was identified as CAKUT related lncRNA, which was coexpressed with multiple known CAKUT associated genes. To validate our findings, we performed knockdown experiments in HEK293 cell line to characterize the trascriptomic profiles regulated by HSALNG0134318 in human embryonic kidney cells.
Project description:Chickarmane2006 - Stem cell switch reversible
Kinetic modeling approach of the transcriptional dynamics of the embryonic stem cell switch.
This model is described in the article:
Transcriptional dynamics of the embryonic stem cell switch.
Chickarmane V, Troein C, Nuber UA, Sauro HM, Peterson C
PLoS Computational Biology. 2006; 2(9):e123
Abstract:
Recent ChIP experiments of human and mouse embryonic stem cells have elucidated the architecture of the transcriptional regulatory circuitry responsible for cell determination, which involves the transcription factors OCT4, SOX2, and NANOG. In addition to regulating each other through feedback loops, these genes also regulate downstream target genes involved in the maintenance and differentiation of embryonic stem cells. A search for the OCT4-SOX2-NANOG network motif in other species reveals that it is unique to mammals. With a kinetic modeling approach, we ascribe function to the observed OCT4-SOX2-NANOG network by making plausible assumptions about the interactions between the transcription factors at the gene promoter binding sites and RNA polymerase (RNAP), at each of the three genes as well as at the target genes. We identify a bistable switch in the network, which arises due to several positive feedback loops, and is switched on/off by input environmental signals. The switch stabilizes the expression levels of the three genes, and through their regulatory roles on the downstream target genes, leads to a binary decision: when OCT4, SOX2, and NANOG are expressed and the switch is on, the self-renewal genes are on and the differentiation genes are off. The opposite holds when the switch is off. The model is extremely robust to parameter changes. In addition to providing a self-consistent picture of the transcriptional circuit, the model generates several predictions. Increasing the binding strength of NANOG to OCT4 and SOX2, or increasing its basal transcriptional rate, leads to an irreversible bistable switch: the switch remains on even when the activating signal is removed. Hence, the stem cell can be manipulated to be self-renewing without the requirement of input signals. We also suggest tests that could discriminate between a variety of feedforward regulation architectures of the target genes by OCT4, SOX2, and NANOG.
This model is hosted on BioModels Database
and identified by: MODEL7957907314
.
To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models
.
To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication
for more information.
Project description:Chickarmane2006 - Stem cell switch irreversible
Kinetic modeling approach of the transcriptional dynamics of the embryonic stem cell switch.
This model is described in the article:
Transcriptional dynamics of the embryonic stem cell switch.
Chickarmane V, Troein C, Nuber UA, Sauro HM, Peterson C
PLoS Computational Biology. 2006; 2(9):e123
Abstract:
Recent ChIP experiments of human and mouse embryonic stem cells have elucidated the architecture of the transcriptional regulatory circuitry responsible for cell determination, which involves the transcription factors OCT4, SOX2, and NANOG. In addition to regulating each other through feedback loops, these genes also regulate downstream target genes involved in the maintenance and differentiation of embryonic stem cells. A search for the OCT4-SOX2-NANOG network motif in other species reveals that it is unique to mammals. With a kinetic modeling approach, we ascribe function to the observed OCT4-SOX2-NANOG network by making plausible assumptions about the interactions between the transcription factors at the gene promoter binding sites and RNA polymerase (RNAP), at each of the three genes as well as at the target genes. We identify a bistable switch in the network, which arises due to several positive feedback loops, and is switched on/off by input environmental signals. The switch stabilizes the expression levels of the three genes, and through their regulatory roles on the downstream target genes, leads to a binary decision: when OCT4, SOX2, and NANOG are expressed and the switch is on, the self-renewal genes are on and the differentiation genes are off. The opposite holds when the switch is off. The model is extremely robust to parameter changes. In addition to providing a self-consistent picture of the transcriptional circuit, the model generates several predictions. Increasing the binding strength of NANOG to OCT4 and SOX2, or increasing its basal transcriptional rate, leads to an irreversible bistable switch: the switch remains on even when the activating signal is removed. Hence, the stem cell can be manipulated to be self-renewing without the requirement of input signals. We also suggest tests that could discriminate between a variety of feedforward regulation architectures of the target genes by OCT4, SOX2, and NANOG.
This model is hosted on BioModels Database
and identified by: MODEL7957942740
.
To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models
.
To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication
for more information.
Project description:RPF-1, a transcription factors encoded by POU6F2 gene, appears to be expressed in the developing nervous system and embryonic kidney. We generated a stable HEK/RPF-1 transfectant expressing the protein in a tetracycline (Tet)-dependent induction and addressed the whole transcriptome regulated by RPF-1. We detected a gross alteration of gene expression that is consistent with its occupancy at proximal promoters, and gel retardation assay and promoter-reporter activity, addressing a few target genes, indicated a dependence by RPF-1 of transcriptional response. GO analysis supports a role for this factor in the genetic programs guiding early differentiation of embryonic kidney and neuronal fate. RPF-1, a transcription factors encoded by POU6F2 gene, appears to be expressed in the developing nervous system and embryonic kidney. We generated a stable HEK/RPF-1 transfectant expressing the protein in a tetracycline (Tet)-dependent induction and addressed the whole transcriptome regulated by RPF-1. We detected a gross alteration of gene expression that is consistent with its occupancy at proximal promoters, and gel retardation assay and promoter-reporter activity, addressing a few target genes, indicated a dependence by RPF-1 of transcriptional response. GO analysis supports a role for this factor in the genetic programs guiding early differentiation of embryonic kidney and neuronal fate. Gene array analysis shows that RPF-1 transcription factor modify the transcriptome of HEK293 cells by regulating a genetic program endowed with developmental programs Comparison of HEK293 cells induced for RPF-1 expression (Tet-) over uninduced control (Tet+) and Mock cells. RPF-1 cDNA was inserted into the pTRE2puro vector to generate stable Tet-inducible KEK293 transfectants. Upon Tet removal from the medium, HEK/RPF-1 transfectants expressed the transcription factor RPF-1. Cells were then seeded in 10 cm dishes, cultured for 48 h either in complete medium supplemented with Tet (+) or in Tet-depleted medium (-), harvested, and spun down before RNA isolation. Comparative analysis between HEK/RPF-1 induced (Tet-) and uninduced (Tet+) transfectants allowed us to identify genes transcriptionally regulated by RPF-1. Residual effects on gene expression due to Tet supplementation into culture media was ruled out by comparison with the Mock transfectant.