Genome wide maps of p53 binding in IMR90 cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE42728 | GEO | 2012/12/05
SECONDARY ACCESSION(S): PRJNA182950
REPOSITORIES: GEO
Similar Datasets
Project description:Oncogene-induced senescence is an anti-proliferative stress response program that acts as a fail-safe mechanism to limit oncogenic transformation and is regulated by the retinoblastoma protein (RB) and p53 tumor suppressor pathways. We identify the atypical E2F family member E2F7 as the only E2F transcription factor potently upregulated during oncogene-induced senescence, a setting where it acts in response to p53 as a direct transcriptional target. Once induced, E2F7 binds and represses a series of E2F target genes and cooperates with RB to efficiently promote cell cycle arrest and limit oncogenic transformation. Disruption of RB triggers a further increase in E2F7, which induces a second cell cycle checkpoint that prevents unconstrained cell division despite aberrant DNA replication. Mechanistically, E2F7 compensates for the loss of RB in repressing mitotic E2F target genes. Examination of p53 binding in either growing or senescent IMR90 cells with different hairpins.
2012-12-05 | E-GEOD-42728 | biostudies-arrayexpress
Project description:Oncogene-induced senescence is an anti-proliferative stress response program that acts as a fail-safe mechanism to limit oncogenic transformation and is regulated by the retinoblastoma protein (RB) and p53 tumor suppressor pathways. We identify the atypical E2F family member E2F7 as the only E2F transcription factor potently upregulated during oncogene-induced senescence, a setting where it acts in response to p53 as a direct transcriptional target. Once induced, E2F7 binds and represses a series of E2F target genes and cooperates with RB to efficiently promote cell cycle arrest and limit oncogenic transformation. Disruption of RB triggers a further increase in E2F7, which induces a second cell cycle checkpoint that prevents unconstrained cell division despite aberrant DNA replication. Mechanistically, E2F7 compensates for the loss of RB in repressing mitotic E2F target genes. Examination of E2F7 binding in either growing or senescent IMR90 cells with different hairpins.
2012-08-25 | E-GEOD-40343 | biostudies-arrayexpress
Project description:Oncogene-induced senescence is an anti-proliferative stress response program that acts as a fail-safe mechanism to limit oncogenic transformation and is regulated by the retinoblastoma protein (RB) and p53 tumor suppressor pathways. We identify the atypical E2F family member E2F7 as the only E2F transcription factor potently upregulated during oncogene-induced senescence, a setting where it acts in response to p53 as a direct transcriptional target. Once induced, E2F7 binds and represses a series of E2F target genes and cooperates with RB to efficiently promote cell cycle arrest and limit oncogenic transformation. Disruption of RB triggers a further increase in E2F7, which induces a second cell cycle checkpoint that prevents unconstrained cell division despite aberrant DNA replication. Mechanistically, E2F7 compensates for the loss of RB in repressing mitotic E2F target genes.
2012-08-25 | GSE40343 | GEO
Project description:Oncogene-induced senescence is an anti-proliferative stress response program that acts as a fail-safe mechanism to limit oncogenic transformation and is regulated by the retinoblastoma protein (RB) and p53 tumor suppressor pathways. We identify the atypical E2F family member E2F7 as the only E2F transcription factor potently upregulated during oncogene-induced senescence, a setting where it acts in response to p53 as a direct transcriptional target. Once induced, E2F7 binds and represses a series of E2F target genes and cooperates with RB to efficiently promote cell cycle arrest and limit oncogenic transformation. Disruption of RB triggers a further increase in E2F7, which induces a second cell cycle checkpoint that prevents unconstrained cell division despite aberrant DNA replication. Mechanistically, E2F7 compensates for the loss of RB in repressing mitotic E2F target genes.
2012-08-25 | GSE40349 | GEO
Project description:Oncogene-induced senescence is an anti-proliferative stress response program that acts as a fail-safe mechanism to limit oncogenic transformation and is regulated by the retinoblastoma protein (RB) and p53 tumor suppressor pathways. We identify the atypical E2F family member E2F7 as the only E2F transcription factor potently upregulated during oncogene-induced senescence, a setting where it acts in response to p53 as a direct transcriptional target. Once induced, E2F7 binds and represses a series of E2F target genes and cooperates with RB to efficiently promote cell cycle arrest and limit oncogenic transformation. Disruption of RB triggers a further increase in E2F7, which induces a second cell cycle checkpoint that prevents unconstrained cell division despite aberrant DNA replication. Mechanistically, E2F7 compensates for the loss of RB in repressing mitotic E2F target genes. To understand the contribution of different genes, especially E2F7 to the expression profile of senescent cells, we infected human IMR90 cells with Ras and different hairpins. The infected population was selected using first with 2 ug/ml puromycin (Sigma) for 2 days, then 100 ug/ml hygromycin B (Roche) for 3 days. RNA was isolated 7 days after the puromycin selection and hybridized to Affymetrix microarrays. We tried to understand the effect of E2F7 in the transcription profile of senescent cells.
2012-08-25 | E-GEOD-40349 | biostudies-arrayexpress
Project description:E2F-transcription factors activate many genes involved in cell cycle progression, DNA repair, and apoptosis. Hence, E2F-dependent transcription must be tightly regulated to prevent tumorigenesis, and therefore metazoan cells possess multiple E2F regulation mechanism. The best-known is the Retinoblastoma protein (RB), which is mutated in many cancers. Atypical E2Fs (E2F7 and -8) can repress E2F-target gene expression independently of RB and are rarely mutated in cancer. Therefore, they may act as emergency brakes in RB-mutated cells to suppress tumor growth. Currently it is unknown if and how RB and atypical E2Fs functionally interact in vivo. Here, we demonstrate that mice with liver-specific combinatorial deletion of Rb and E2f7/8 have reduced life spans compared to E2f7/8 or Rb deletion alone. This was associated with increased proliferation and enhanced malignant progression of liver tumors. Hence, atypical repressor E2Fs and RB cooperatively act as tumor suppressors in hepatocytes. We propose that the complex interactions between atypical E2Fs and RB on maintenance of genetic stability underlie this context-dependency.
2021-04-22 | GSE172508 | GEO
Project description:SV40 transforms cells through the action of two oncoproteins, large T antigen and small t antigen. Small t antigen targets phosphatase PP2A, while large T antigen stimulates cell proliferation and survival by action on multiple proteins, including the tumor suppressors Rb and p53. Large T antigen also binds components of the transcription initiation complex and several transcription factors. We examine global gene expression in SV40-transformed REF52 cells. SV40 transformation alters the expression of approximately 480 cellular genes. Much of this regulation is consistent with T antigen action on the Rb-E2F pathway.
2009-09-01 | GSE7836 | GEO
Project description:E2F transcription factors are central regulators of cell cycle progression and cell fate decisions in mammalian cells. E2F4 is a transcriptional repressor implicated in cell cycle arrest and whose repressive activity depends on its interaction with members of the RB family. E2F4 often represents the predominant E2F activity in cells. Here we show that E2F4 is important for the proliferation and the survival of mouse embryonic stem cells. In these cells, E2F4 acts in part as a transcriptional activator that promotes the expression of cell cycle genes. Importantly, this role for E2F4 is completely independent of the RB family. Accordingly, an unbiased analysis of the E2F4 interactome shows that E2F4 functionally interacts with chromatin regulators associated with gene activation in RB family-mutant cells. Taken together, our findings uncover a non-canonical role for E2F4 that reveal novel insights into the biology of rapidly dividing cell types.
2019-04-26 | PXD008796 | Pride
Project description:We have developed cdk4/hTERT-immortalized normal human bronchial epithelial cells (HBECs) to study lung cancer pathogenesis. By studying the oncogenic effect of common lung cancer alterations (p53, KRAS, and c-MYC) we demonstrate the ability of this model to characterize the stepwise transformation of bronchial epithelial cells to full malignancy. Using HBECs derived from multiple individuals we found: 1) the combination of five genetic alterations (p53, KRASV12, c-MYC, CDK4 and hTERT) is sufficient for full tumorigenic conversion of HBECs; 2) high levels of KRASV12 are required for full malignant transformation of HBECs, however these levels also stimulate oncogene-induced senescence; 3) RAS-induced senescence is largely bypassed with loss of p53 function; 4) over-expression of c-MYC greatly enhances malignancy but only in the context of sh-p53+KRASV12; 5) HBECs from different individuals vary in their sensitivity to transformation by these oncogenic manipulations; 6) serum-induced epithelial-to-mesenchymal transition (EMT) increases in vivo tumorigenicity; 7) genetically-identical clones of transformed HBECs exhibit pronounced differences in tumor growth, histology, and differentiation as well as sensitivity to standard platinum-based chemotherapies; and 8) an mRNA signature derived from tumorigenic and non-tumorigenic clones is predictive of outcome in lung cancer patients. Collectively, we demonstrate this HBEC model system can be used to study the effect of oncogenic mutations on malignant progression, oncogene-induced senescence, and EMT along with clinically translatable applications such as development of prognostic signatures and drug response phenotypes. Human bronchial epithelial cells (HBECs) immortalized with cdk4 and hTERT were transformed with p53 knockdown, KrasV12 and cMYC over-expression and profiled on Illumina HumanHT-12 V4.0 expression beadchips. Transformed HBECs were grown in two different growth media: KSFM (defined, serum-free medium) or R10 (RPMI with 10% FBS) as indicated. Clones were isolated from HBECs with sh-p53 + KrasV12 and sh-p53 + KrasV12 + cMYC.
2013-07-01 | E-GEOD-40828 | biostudies-arrayexpress
Project description:Most E2F-binding sites repress transcription through the recruitment of Retinoblasoma (RB) family members until the end of the G1 cell-cycle phase. Although the MYB promoter contains an E2F-binding site, its transcription is activated shortly after the exit from quiescence, before RB family members inactivation, by unknown mechanisms. We had previously uncovered a nuclear factor distinct from E2F, Myb-sp, whose DNA-binding site overlapped the E2F element and had hypothesized that this factor might overcome the transcriptional repression of MYB by E2F-RB family members. We have purified Myb-sp and discovered that Myc-associated zinc finger proteins (MAZ) are major components. We show that various MAZ isoforms are present in Myb-sp and activate transcription via the MYB-E2F element. Moreover, while forced RB or p130 expression repressed the activity of a luciferase reporter driven by the MYB-E2F element, co-expression of MAZ proteins not only reverted repression, but also activated transcription. Finally, we show that MAZ binds the MYB promoter in vivo, that its binding site is critical for MYB transactivation, and that MAZ knockdown inhibits MYB expression during the exit from quiescence. Together, these data indicate that MAZ is essential to bypass MYB promoter repression by RB family members and to induce MYB expression.
2017-10-04 | PXD006857 | Pride