Figure 12.

Blocking STIM1 and ORAI greatly attenuate T lymphocyte activation. Agonist was applied from 200 s to 1200 s. [Ca²⁺]_o was held at 2,0 mM throughout the simulation. (A) Block of the channel conductance of ORAI1 (red) or blocking the Ca²⁺ sensitivity of STIM1 (green) greatly attenuate the [Ca²⁺]_cyt transient compared to control (black). Blocking the cooperativity of STIM1 (blue) but still allowing monomers to activate ORAI1 has little effect the [Ca²⁺]_cyt transient. (B) Block of the channel conductance of ORAI1 (red) or blocking the Ca²⁺ sensitivity of STIM1 (green) greatly attenuate NFAT translocation to the nucleus compared to control (black). Blocking the cooperativity of STIM1 (blue) but still allowing monomers to activate ORAI1 has little effect on NFAT translocation to the nucleus.