This Event is licensed under the Creative Commons BY-SA license. This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, so long as attribution is given to the creator. The license allows for commercial use. If you remix, adapt, or build upon the material, you must license the modified material under identical terms.
Event: 981
Key Event Title
Reduction, NFAT/AP-1 complex formation
Short name
Biological Context
Level of Biological Organization |
---|
Cellular |
Cell term
Cell term |
---|
T cell |
Organ term
Organ term |
---|
immune system |
Key Event Components
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
AOP Name | Role of event in AOP | Point of Contact | Author Status | OECD Status |
---|---|---|---|---|
Immunosuppression | KeyEvent | Takumi Ohishi (send email) | Open for comment. Do not cite | WPHA/WNT Endorsed |
Taxonomic Applicability
Life Stages
Life stage | Evidence |
---|---|
All life stages | High |
Sex Applicability
Term | Evidence |
---|---|
Unspecific | High |
Key Event Description
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).
Besides IL-2, NFAT is known to bind cooperatively at the promoters of other T-cell cytokines, such as Interleukin-4 (IL-4) (Macian et al. 2005).
Treatment of activated T cells with FK506 at 100ng/mL (124nM) or CsA at 500ng/mL (416nM) for 2 hours hinders the formation of functional NFAT/AP-1 in the nucleus (Flanagan et al. 1991).
How It Is Measured or Detected
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
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).
References
- 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.
- 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.
- 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.
- Macian, F. (2005). NFAT proteins: key regulators of T-cell development and function. Nature reviews. Immunology. 5(6): 472-84.
- Schreiber, SL., and Crabtree, GR. (1992). The mechanism of action of cyclosporin A and FK506. Immunology Today 13(4): 136-42.