| Abstract: | We determined that the phosphatidylinositol (PI) cycles in both sea urchin sperm and eggs are necessary for normal fertilization, and that the PI cycle in sea urchin zygotes is involved in control of mitosis. The PI cycle is involved in Ca++ homeostasis so our data are direct evidence that Ca++ is involved with control of mitosis and fertilization. We implicated the PI cycle by adding Li+ to sea urchin eggs, sperm, or zygotes: those effects of Li+ due to effects on the PI cycle were overcome by myo-inositol but not by its optical isomer, scyllitol, and not by mannitol. |
