Sensory rhodopsin II (rainbow colored) embedded in a lipid bilayer (heads red and tails blue) with ترارسانی (Gt) below it. Gtα is colored red, Gtβ blue, and Gtγ yellow. There is a bound گوانوزین دیفسفات molecule in the Gtα-subunit and a bound retinal (black) in the rhodopsin. The N-terminus of rhodopsin is red and the C-terminus blue. Presumed anchoring of transducin to the membrane has been drawn in black.