Analysis of GPCR/Ion Channel Interactions
Voltage-gated calcium channels are key regulators of calcium homeostasis in excitable cells. A number of cellular signaling pathways serve to fine tune calcium channel activity, including the activation of G protein-coupled receptors. Besides regulating channel activity via second messengers, GPCRs can also physically associate with calcium channels to directly regulate their functions, as well as their trafficking to and from the plasma membrane. Here we provide some methods that can be used to examine channel–receptor interactions and co-trafficking. While we focus on voltage-gated calcium channels, the techniques described herein are broadly applicable to other types of channels.
Key wordsVoltage-gated calcium channel G protein-coupled receptor Luminometry Confocal microscopy
We thank Dr. Bourinet for creating an HA-tagged version of the Cav2.2 channel. GWZ is Scientist of the Alberta Heritage Foundation for Medical Research, and a Canada Research Chair. Work described in this chapter was supported by grants from the Canadian Institutes of Health Research.
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