API

Event: 981

Key Event Title

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Reduction, NFAT/AP-1 complex formation

Short name

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Reduction, NFAT/AP-1 complex formation

Biological Context

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Level of Biological Organization
Cellular

Cell term

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Cell term
T cell


Organ term

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Organ term
immune system


Key Event Components

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Process Object Action
cytokine production involved in inflammatory response NFAT activation molecule 1 decreased
cell activation increased

Key Event Overview


AOPs Including This Key Event

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AOP Name Role of event in AOP
Immunosuppression KeyEvent

Stressors

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Taxonomic Applicability

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Term Scientific Term Evidence Link
Homo sapiens Homo sapiens High NCBI
Mus musculus Mus musculus High NCBI

Life Stages

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Life stage Evidence
All life stages High

Sex Applicability

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Term Evidence
Mixed High

Key Event Description

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Activated nuclear factor of activated T cells (NFAT) that has localized to the nucleus binds cooperatively at the site of the Interleukin-2 (IL-2) promoter with activator protein-1 (AP-1), which is a heterodimer comprising a Fos and a Jun protein (Schreiber and Crabtree 1992, Jain et al. 1992), thereby inducing transcription of IL-2 (Jain et al. 1993). Interfered nuclear localization of NFAT, induced by FK506, hinders the formation of the functional NFAT/AP-1 complexes necessary to binding at the site of IL-2 promoters (Flanagan et al. 1991).

NFAT is known to bind cooperatively at the promoters of Interleukin-4 (IL-4) and other T-cell cytokines as well as that of IL-2 (Macian et al. 2005).


How It Is Measured or Detected

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Reductions in NFAT/AP-1 complex formation can be detected using a gel shift assay to test nuclear extracts from either stimulated or unstimulated Ar-5 T cells with radio-labelled NFAT binding oligonucleotide from murine IL-2 promoter. Anti-Fos and anti-Jun antibodies are used to examine NFAT/AP-1 complex formation (Jain et al. 1992).


Domain of Applicability

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CN-NFAT system functionality is common among mammalian species, including humans and rodents. It is also possible that FK506-induced interference with NFAT/AP-1 complex formation at the promoter site of the IL-2 gene is common among mammalian T cells, including those of humans and rodents (Flanagan et al. 1991).


Evidence for Perturbation by Stressor



References

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  1. Flanagan, W.M., Corthésy, B., Bram, R.J. and Crabtree, G.R. (1991). Nuclear association of a T-cell transcription factor blocked by FK-506 and cyclosporin A. Nature 352 (6338): 803-7.
  2. Jain, J., McCaffrey, P. G., Valge-Archer, V. E. and Rao, A. (1992). Nuclear factor of activated T cells contains Fos and Jun. Nature. 356(6372): 801-804.
  3. Jain, J., Miner, Z. and Rao, A. (1993). Analysis of the preexisting and nuclear forms of nuclear factor of activated T cells. Journal of immunology. 151(2): 837-848.
  4. Macian, F. (2005). NFAT proteins: key regulators of T-cell development and function. Nature reviews. Immunology. 5(6): 472-84.
  5. Schreiber, SL., and Crabtree, GR. (1992). The mechanism of action of cyclosporin A and FK506. Immunology Today 13(4): 136-42.