PRESENCE OF 1-METHYLADENINE IN SEA URCHIN GONAD AND ITS RELATION TO OOCYTE MATURATION

A water extract of sea urchin ovary was found to induce maturation of starfish oocytes in vitro. The presence of the active substance was demonstrated in ovaries of the sea urchins, Pseudocentrotus depressus, Anthocidaris crassispina and Hemicentrotus pulcherrimus, and the sand dollars, Clypeaster japonicus and Peronella japonica. The active substance was also contained in the testes of these echinoids. That the content of this substance increases during the reproductive season was demonstrated with Anthocidaris gonads. The active substance present in ovary or testis of the sea urchins was successfully extracted with 85% ethanol and purified with gel-filtrations on Sephadex G-15 columns after washing with chloroform and ether. The purified active substances were the same and were identified as 1-1-methyladenine by thin layer chromatography. 1-Methyladenine was found to be effective in inducing oocyte maturation in Anthocidaris crassispina in vitro. Therefore, 1-methyladenine seems to play an important role in oocyte maturation in echinoids as well as in asteroids.