Binding of [125I]concanavalin A by interspecific amoeba hybrids.

Two types of interspecific amoeba hybrids, viz. PnIc (Amoeba proteus nucleus in A. indica cytoplasm) and InPc (A. indica nucleus in A. proteus cytoplasm), were tested for their [125I]Concanavalin A (Con A) binding activity at different periods of time. The cell surface binding of the labelled Con A was reduced to approx. 40 and 75% in the PnIc and InPc cells, respectively, 96 h after the cells were made hybrids. A significant increase in the binding of radioactive Con A was observed after the homologous nucleus was back transferred into InPc cells, but not in PnIc cells. No significant difference in the binding of the radioactive Con A was found between the progeny of the hybrid amoebae and the control amoebae. The Con A binding activity of the interspecific amoebae has been discussed in relation to the changes in the cytoplasmic membrane structures which presumably play a role in the formation of cell surface in the amoebae.