Dataset Information

HIF-1alpha and HIF-2alpha ChIP-chip profiling in intestinal epithelial cells

ABSTRACT: Intestinal epithelia exist in a uniquely dynamic oxygen tension microenvironment. Adaptive responses to hypoxia in mammalian cells are regulated largely by hypoxia inducible factor (HIF) transcriptional complexes. Functional HIF exists as an obligate alpha/beta heterodimer, comprising both a constitutive subunit (HIF-1beta), and an oxygen-labile regulatory (alpha) component. To date, three regulatory subunits have been identified, namely HIF-1alpha, HIF-2alpha, and HIF-3alpha, with the highest level of sequence homology conserved between HIF-1alpha and HIF-2alpha. Despite their concurrent expression in intestinal epithelial cells, HIF-1 and HIF-2 play non-redundant roles in the regulation of an overlapping but distinct set of gene targets. In this study, we performed ChIP-on-chip analysis of chromatin isolated from hypoxic intestinal epithelia to delineate HIF-1 and HIF-2 specific loci.

ORGANISM(S): Homo sapiens

PROVIDER: GSE43108 | GEO | 2013/11/05

SECONDARY ACCESSION(S): PRJNA226623

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:The response of cells to hypoxia is characterised by co-ordinated regulation of many genes. Studies of the regulation of the expression of many of these genes by oxygen has implicated a role for the heterodimeric transcription factor hypoxia inducible factor (HIF). The mechanism of oxygen sensing which controls this heterodimeric factor is via oxygen dependent prolyl and asparaginyl hydroxylation by specific 2-oxoglutarate dependent dioxygenases (PHD1, PHD2, PHD3 and FIH-1). Whilst HIF appears to have a major role in hypoxic regulation of gene expression, it is unclear to what extent other transcriptional mechanisms are also involved in the response to hypoxia. The extent to which 2-oxoglutarate dependent dioxygenases are responsible for the oxygen sensing mechanism in HIF-independent hypoxic gene regulation is also unclear. Both the prolyl and asparaginyl hydroxylases can be inhibited by dimethyloxalylglycine (DMOG). Such inhibition can produce activation of the HIF system with enhanced transcription of target genes and might have a role in the therapy of ischaemic disease. We have examined the extent to which the HIF system contributes to the regulation of gene expression by hypoxia, to what extent 2-oxoglutarate dependent dioxygenase inhibitor can mimic the hypoxic response and the nature of the global transcriptional response to hypoxia. We have utilised microarray assays of mRNA abundance to examine the gene expression changes in response to hypoxia and to DMOG. We demonstrate a large number of hypoxically regulated genes, both known and novel, and find a surprisingly high level of mimicry of the hypoxic response by use of the 2-oxoglutarate dependent dioxygenase inhibitor, dimethyloxalylglycine. We have also used microarray analysis of cells treated with small interfering RNA (siRNA) targeting HIF-1alpha and HIF-2alpha to demonstrate the differing contributions of each transcription factor to the transcriptional response to hypoxia. Candidate transcripts were confirmed using an independent microarray platform and real-time PCR. The results emphasise the critical role of the HIF system in the hypoxic response, whilst indicating the dominance of HIF-1alpha and defining genes that only respond to HIF-2alpha. Keywords: Hypoxia response, gene knockdown, chemical treatment

Dataset Information

HIF-1alpha and HIF-2alpha ChIP-chip profiling in intestinal epithelial cells

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure