Dataset Information

Multilevel regulation of HIF-1 signaling by TTP.

ABSTRACT: Hypoxia-inducible factor-1 (HIF-1) is a well-studied transcription factor mediating cellular adaptation to hypoxia. It also plays a crucial role under normoxic conditions, such as in inflammation, where its regulation is less well understood. The 3'-untranslated region (UTR) of HIF-1? mRNA is among the most conserved UTRs in the genome, hinting toward posttranscriptional regulation. To identify potential trans factors, we analyzed a large compilation of expression data. In contrast to its known function of being a negative regulator, we found that tristetraprolin (TTP) positively correlates with HIF-1 target genes. Mathematical modeling predicts that an additional level of posttranslational regulation of TTP can explain the observed positive correlation between TTP and HIF-1 signaling. Mechanistic studies revealed that TTP indeed changes its mode of regulation from destabilizing to stabilizing HIF-1? mRNA upon phosphorylation by p38 mitogen-activated protein kinase (MAPK)/MAPK-activated protein kinase 2. Using a model of monocyte-to-macrophage differentiation, we show that TTP-driven HIF-1? mRNA stabilization is crucial for cell migration. This demonstrates the physiological importance of a hitherto-unknown mechanism for multilevel regulation of HIF-1? in normoxia.

SUBMITTER: Fahling M

PROVIDER: S-EPMC3469526 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Multilevel regulation of HIF-1 signaling by TTP.

Fähling Michael M Persson Anja Bondke AB Klinger Bertram B Benko Edgar E Steege Andreas A Kasim Mumtaz M Patzak Andreas A Persson Pontus B PB Wolf Gunter G Blüthgen Nils N Mrowka Ralf R

Molecular biology of the cell 20120823 20

Hypoxia-inducible factor-1 (HIF-1) is a well-studied transcription factor mediating cellular adaptation to hypoxia. It also plays a crucial role under normoxic conditions, such as in inflammation, where its regulation is less well understood. The 3'-untranslated region (UTR) of HIF-1α mRNA is among the most conserved UTRs in the genome, hinting toward posttranscriptional regulation. To identify potential trans factors, we analyzed a large compilation of expression data. In contrast to its known ...[more]

PMID: 22918951

Similar Datasets

Project description:Natural killer (NK) cells belong to the first line of host defense against infection and cancer. Cytokines, including interleukin-15 (IL-15), critically regulate NK cell activity, resulting in recognition and direct killing of transformed and infected target cells. NK cells have to adapt and respond in inflamed and often hypoxic areas. Cellular stabilization and accumulation of the transcription factor hypoxia-inducible factor-1? (HIF-1?) is a key mechanism of the cellular hypoxia response. At the same time, HIF-1? plays a critical role in both innate and adaptive immunity. While the HIF-1? hydroxylation and degradation pathway has been recently described with the help of mathematical methods, less is known concerning the mechanistic mathematical description of processes regulating the levels of HIF-1? mRNA and protein. In this work we combine mathematical modeling with experimental laboratory analysis and examine the dynamic relationship between HIF-1? mRNA, HIF-1? protein, and IL-15-mediated upstream signaling events in NK cells from human blood. We propose a system of non-linear ordinary differential equations with positive and negative feedback loops for describing the complex interplay of HIF-1? regulators. The experimental design is optimized with the help of mathematical methods, and numerical optimization techniques yield reliable parameter estimates. The mathematical model allows for the investigation and prediction of HIF-1? stabilization under different inflammatory conditions and provides a better understanding of mechanisms mediating cellular enrichment of HIF-1?. Thanks to the combination of in vitro experimental data and in silico predictions we identified the mammalian target of rapamycin (mTOR), the nuclear factor-?B (NF-?B), and the signal transducer and activator of transcription 3 (STAT3) as central regulators of HIF-1? accumulation. We hypothesize that the regulatory pathway proposed here for NK cells can be extended to other types of immune cells. Understanding the molecular mechanisms involved in the dynamic regulation of the HIF-1? pathway in immune cells is of central importance to the immune cell function and could be a promising strategy in the design of treatments for human inflammatory diseases and cancer.

Dataset Information

Multilevel regulation of HIF-1 signaling by TTP.

Publications

Multilevel regulation of HIF-1 signaling by TTP.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets