Figure 11. InsP₃ activates I_CRAC in weak buffer provided mitochondria are energised.

A, time course of activation of I_CRAC in the presence of the mitochondrial cocktail (○). I_CRAC does not activate in weak Ca²⁺ buffer in response to InsP₃ alone (•). B, steady-state I-V relationships are shown for the cells in A. C, the effects of cocktail are suppressed by preventing mitochondrial Ca²⁺ uptake by either depolarising mitochondria (pre-treatment with antimycin A (5 μg ml⁻¹) and oligomycin (0.5 μg ml⁻¹)) or inhibiting the uniporter with ruthenium red. D, the presence of cocktail dramatically increases the fraction of cells that respond to InsP₃ in weak Ca²⁺ buffer. ^*P < 0.01.