For example, the prefoldin that is used in the formation of actin also transfers α or β tubulin to a cytosolic chaperonin. The prefoldin, however, does not form a ternary complex with tubulin and chaperonin. Once the tubulins are in contact with the chaperonin, the prefoldin automatically lets go and leaves the active site, due to its high affinity for the chaperonin molecule. Once the prefoldin is in contact with the chaperonin protein, it loses its affinity for the unfolded target protein.