Calcineurin–nuclear factor of activated T cells signaling pathway (Calcineurin–NFAT pathway)

The **Calcineurin–NFAT signaling pathway** is a central intracellular signal transduction cascade integrating calcium signals to regulate gene expression, principally in immune cells. Calcineurin is a Ca2+-activated serine/threonine phosphatase that, upon elevation of intracellular calcium, dephosphorylates nuclear factor of activated T cells (NFAT) transcription factors. This leads to NFAT nuclear translocation and activation of gene programs related to immune cell activation, differentiation, cytokine production, and other cellular processes[1][2][4][5][7]. The pathway underlies fundamental aspects of adaptive and innate immunity, controls T cell responses, and participates in angiogenesis, nervous system development, and differentiation of other lineages including osteoclasts and endothelial cells[1][3][4][6][7]. Dysregulation or persistent activation of calcineurin–NFAT signaling is implicated in autoimmune diseases, chronic inflammation, cancers (including leukemia and solid tumors), neurodegeneration, and cardiovascular pathology[5][2][8]. Clinically, drugs such as cyclosporine and tacrolimus inhibit calcineurin to treat autoimmune and inflammatory conditions, though use is limited by safety concerns such as immunosuppression and organ toxicities[2][5]. The pathway’s functional biomarkers include NFAT nuclear localization and calcineurin activity, and it is recognized as a pivotal therapeutic target in immunology and oncology.

Other names

Calcium–calcineurin–NFAT pathwayCa2+/calcineurin/NFAT pathwayCalcineurin/NFAT axisCalcineurin–NFAT signaling cascade

Inhibition of calcineurin-mediated dephosphorylation of NFAT, preventing NFAT nuclear translocation and gene activation[2][5][8].