Abstract: | The oocytes of the starfish Aphelasterias japonica were divided into anuclear (cytoplasts) and nuclear (germinal vesicles) fragments by centrifugation in a Ficoll gradient with cytochalasin B. Cell hybrids between the oocytes and the cytoplasts were then prepared with the aid of polyethylene glycol treatment. These cell hybrids were capable of responding to 1-methyladenine by maturation. |