Amoeba proteus expresses a single AQP that is present in the contractile vacuole
complex required for osmoregulation, whereas Dictyostelium discoideum expresses four AQPs, of which two are present in the single-celled amoeboidal stage and two more in the later multicellular stages preceding spore formation.
The contractile vacuole
lies above the macronucleus.
The parasite was characterized as a large trichodinid with disc-shaped body; convex adoral surface with ciliature of about 370[degrees] [+ or -] 6.7 (360-384) measured in 17 specimens; central contractile vacuole
; aboral side with slightly concave adhesive disc provided by 26.0 [+ or -] 1.2 (23-29, 55) denticles and central area of the adhesive disc provided with dark granules.
cruzi, the etiologic agent of Chagas disease, and Peter Rohloff showed that this protein is translocated to the contractile vacuole
upon hypo-osmotic stress.