Dr. Masato Kiyomoto
I am studying on the development and reproduction of echinoids. The sea urchin egg has a polarity, many kind of cells forming skeleton, muscle and digestive tract appear from the one side of egg (vegetal pole). It is well known that the cell line of skeletogenesis is a first group whose cell fate is decided at first. We have examined the developmental potential of each part in vegetal side and shown that most of all vegetal side has a potential of skeletogenesis in the culture after a separation to a small volume. It is considered that the skeletogenic potential is suppressed and each part is regulated to the normal cell fate in embryogenesis. Some of metal ions and chemicals have an effect on the morphogenesis of digestive tract. Exogastrula induced by Estrogen or Li, in which the digestive tract project to the outside, is examined. The roles of steroid hormones, such as estrogens, are also examined on the yolk protein production and gametogenesis.