Measuring Ca2+-Dependent Modulation of Voltage-Gated Ca2+ (Cav) Channels in HEK-293T cells

摘要

Voltage-gated Ca²⁺ (Cav) channels regulate a variety of biological processes, such as muscle contraction, gene expression, and neurotransmitter release. Cav channels are subject to diverse forms of regulation, including those involving the Ca²⁺ ions that permeate the pore. High voltage-activated Cav channels undergo Ca²⁺-dependent inactivation (CDI) and facilitation (CDF), which can regulate processes such as cardiac rhythm and synaptic plasticity. CDI and CDF slightly differ between Cav1 (L-type) and Cav2 (P/Q-, N-, and R-type) channels. Human embryonic kidney cells transformed with SV40 large T-antigen (HEK-293T) are advantageous for studying CDI and CDF of a particular type of Cav channel. HEK-293T cells do not express endogenous Cav channels, and Cav channels can be exogenously expressed at high levels in these cells through transient transfection. This protocol explains how to characterize and analyze Ca²⁺-dependent modulation of recombinant Cav channels in HEK-293T cells.