DEVELOPMENTAL-CHANGES OF METALLOTHIONEIN CONTENT AND SYNTHESIS IN SEA-URCHIN PARACENTROTUS-LIVIDUS EMBRYOS

The changes in metallothionein content during development of embryos have been studied by gel permeation chromatography of the cytosolic proteins. In unfertilized eggs, the maternal metallothionein pool is relatively high, but decreases through cleavage until the late blastula stage, increasing again at the gastrula stage. metallothionein synthesis in embryos incubated with [35S]-cysteine is higher at the gastrula stage than at the earlier stages. These results suggest that the changes in metallothionein content and synthesis may be somehow correlated to the metabolic activity of the growing embryo.