A contractile vacuole complex is involved in osmoregulation in Trypanosoma cruzi

Exp Parasitol. 2008 Jan;118(1):17-24. doi: 10.1016/j.exppara.2007.04.013. Epub 2007 May 10.

Abstract

Acidocalcisomes are dense, acidic organelles with a high concentration of phosphorus present as pyrophosphate and polyphosphate complexed with calcium and other cations. Acidocalcisomes have been linked to the contractile vacuole complex in Chlamydomonas reinhardtii, Dictyostelium discoideum, and Trypanosoma cruzi. A microtubule- and cyclic AMP-mediated fusion of acidocalcisomes to the contractile vacuole complex in T. cruzi results in translocation of aquaporin and the resulting water movement which, in addition to swelling of acidocalcisomes, is responsible for the volume reversal not accounted for by efflux of osmolytes. Polyphosphate hydrolysis occurs during hyposmotic stress, probably increasing the osmotic pressure of the contractile vacuole and facilitating water movement.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Adaptation, Physiological
  • Animals
  • Aquaporins / physiology
  • Cyclic AMP / physiology
  • Models, Biological
  • Osmotic Pressure
  • Trypanosoma cruzi / physiology*
  • Trypanosoma cruzi / ultrastructure*
  • Vacuoles / physiology*
  • Water-Electrolyte Balance / physiology*

Substances

  • Aquaporins
  • Cyclic AMP