Figure 2.

Gα subunits provide a PM-targeting second signal for Gβγ. COS-1 cells were transfected with GFP-Gγ₁ (a–d) or GFP-Gγ₂ (e–h) and cotransfected with Gβ₁ alone (a, e), Gβ₁ and Gα_i2 (b, f), Gβ₁ and Gα_q (c, g), or Gβ₁ and Gα_s (d, h) and imaged as in Figure 1. Arrows indicate PM, arrowheads indicate Golgi, and the positions of nuclei are marked (N). a and e, The nuclear envelope and Golgi are purposely overexposed to reveal the peripheral reticulum of the ER. Bars, 10 μm.