INDUCTION OF OOCYTE MATURATION BY DISULFIDE-REDUCING AGENT IN THE SEA CUCUMBER, STICHOPUS JAPONICUS

1-Methyladenine (1-MeAde) is known to be a natural inducer of starfish oocyte maturation. Disulfide-reducing agents such as dithiothreitol (DTT) and 2, 3-dimercapto-1-propanol (BAL) are known to mimic the action of 1-MeAde in inducing starfish oocyte maturation. Although 1-MeAde failed to induce oocyte maturation in sea cucumbers, breakdown of germinal vesicles and subsequent meiotic behaviour of chromosomes were induced by the treatment with DTT in the pronase-treated oocytes of the sea cucumber, Stichopus japonicus. These findings suggest that reduction of disulfide bonds plays an important role in triggering oocyte maturation in some marine forms such as echinoderms.