The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 

Utilization of an NF-ATp binding promoter element for EGR3 expression in T cells but not fibroblasts provides a molecular model for the lymphoid cell-specific effect of cyclosporin A.

Cyclosporin A (CsA) mainly exerts its immunosuppressive action by selectively inhibiting Ca2+/calcineurin-dependent gene transcription in lymphoid cells. A model explaining the tissue-specific effect of this drug on gene expression has not been established to date, since none of the known intracellular targets of CsA (e.g., cyclophilins, calcineurin, and NF-AT) is lymphoid cell specific. To investigate this issue, we performed a detailed comparative analysis of the promoter regulating the two-signal-dependent (Ca2+ ionophore plus phorbol myristate acetate [PMA]), CsA-sensitive expression of EGR3 in T cells and the one-signal-dependent (PMA), CsA-insensitive expression of EGR3 in fibroblasts. As a result, we identified a 27-bp promoter element functionally interacting with transcription factors NF-ATp and NF-ATc that is crucial for the CsA-sensitive expression of the EGR3 gene in T cells. In contrast, the same element was without function in fibroblasts, and other, CsA-insensitive promoter regions were found to be responsible for EGR3 gene expression in these cells. The inactivity of the 27-bp element in fibroblasts was apparently due to insufficient expression levels of NF-ATp, since overexpression of NF-ATp, but not NF-ATc, restored the two-signal phenotype and CsA sensitivity of EGR3 promoter induction in these cells. The differential usage of an NF-AT binding site explains the selective effect of CsA on EGR3 gene expression in T cells versus fibroblasts and may represent one of the basic mechanisms underlying the tissue specificity of CsA.[1]

References

 
WikiGenes - Universities