G protein beta-gamma refers to a component of heterotrimeric G proteins, which play a crucial role in cellular signaling. These proteins are composed of three subunits: alpha, beta, and gamma. When a receptor on the cell surface is activated, the alpha subunit exchanges GDP for GTP, leading to the dissociation of the beta-gamma complex from the alpha subunit. The beta-gamma complex can then interact with various effectors, such as ion channels and enzymes, to propagate the signal within the cell. This interaction is essential for many physiological processes, including neurotransmission and hormonal regulation.