Effects of puromycin on the differentiation of the freshwater sponge: Ephydatia fluviatilis.

As could be expected, the most general effect of puromycin on the hatching and differentiation of freshwater sponges from their gemmules is complete inhibition. However, when gemmules are treated with 7-microgram/ml puromycin from the beginning of incubation, hatching does occur, and the escaping archaeocytes secrete an unusual number of spicules, while failing to differentiate in any other way or to undertake any morphogenesis. It is suggested that puromycin-treated archaeocytes could provide a suitable material for the study of spicule formation.