Figure 7.

GPN-mediated release of Ca²⁺ is increased in the absence of GIMAP5. Peripheral CD4⁺ T lymphocytes purified from Gimap5^lyp/lyp and control rats were loaded with Fura-2 and intracellular Ca²⁺ was measured as described. The arrow indicates the time of addition of GPN (100 µM). Cytosolic Ca²⁺ was measured following addition of GPN in the absence (A) or presence (B) of extracellular Ca²⁺. The histograms represent the area under curve (AUC) and the peak values. Student’s t-test (**p < 0.005). (C) Cytosolic Ca²⁺ was measured using Fura-2-labeled stable transfectants of the indicated GIMAP5 constructs. The cells were maintained in Ca²⁺-free medium (0 mM Ca²⁺ and 0.5 mM EGTA), and GPN and TG were added sequentially as indicated before adding Ca²⁺ to the extracellular medium. (D) Ca²⁺ release from stable transfectants of the vector control or GIMAP5v2 following addition of GPN in the presence of extracellular Ca²⁺. (E) Cytosolic Ca²⁺ was measured following addition of TG or GPN in the presence of extracellular Ca²⁺ in T lymphocytes pretreated or not with nocodazole (2 µM) for 30 min.