Simultaneous Detection of Ca2+ and Diacylglycerol Signaling in Living Cells
Figure 2
The responses of Green Downward DAG and Upward DAG sensors.
(A) Carbachol stimulation of the M1 receptor on cells expressing the Downward DAG sensor produces a 40% loss in fluorescence that occurs over ∼15 seconds (mean fluorescence over time of 4 cells). (B) The Upward DAG sensor shows a fluorescence increase of 45% over a similar time scale. (C) The signals generated by either sensor return to baseline quite slowly. (D) The apparent EC50 for carbacol-stimulated Upward DAG response is 3.5 uM. (E) The carbachol stimulation does not appear to activate all of the sensor pool in the cell since direct activation of the sensors with a subsequent application of PDBu produces an additional increase in fluorescence.