Cytochemical localization of adenylate cyclase and 3',5'-nucleotide phosphodiesterase in Dictyostelium.

Cytochemical localizations of adenylate cyclase and 3′,5′-nucleotide phosphodiesterase were performed on aggregating Dictytostelium discoideum myxamoebae. The adenylate cyclase reaction product was localized on the inner surface of the plasma membrane. The phosphodiesterase reaction product was localized on the outer surface of the plasma membrane. Differences in enzyme activity were noted according to the state of cell (isolated or aggregated) and according to the cell position in larger aggregates. Heavy precipitation indicative of adenylate cyclase activity was not observed in isolated amoebae, but was often observed in streams and in some cells of aggregates. The precipitation indicative of phosphodiesterase activity could be found in isolated amoebae and in peripheral cells of aggregates.