Fertilization-induced change in the respiratory rate in eggs of several marine invertebrates

Abstract

1. 1. Fertilization enhances the respiratory rate in eggs of sea urchin and tunicate but hardly increases it in oyster, mussel, echiuroid, polychaete and starfish. In all examined species, fertilization increased the rate under infinite stimulation by 2,4-dinitrophenol. 2. 2. In these eggs, the responses of respiration to phenazine methosulfate and 2,4-dinitrophenol suggest that fertilization releases blockages of mitochondrial respiration and its coupling to oxidative phosphorylation. 3. 3. In the former two species, the blockage of respiration is quite strong in unfertilized eggs and hence, its release by fertilization probably becomes apparent in spite of intensified ADP control by releasing the blockage in coupling to phosphorylation. © 1988.