It is generally agreed that fertilization in deuterostomes is accompanied by a large intracellular calcium wave that triggers the onset of development, but we still do not know exactly how the calcium wave is generated. The question has two parts: how does interaction of sperm and egg initiate the calcium wave, and how does the calcium wave spread across the cell? Two provisional answers are available to the first part of the question, one involving receptor-G-protein interactions of the sort that mediate trans-membrane signal transduction in somatic cells, the other injection of an activating messenger when sperm and egg fuse. Both these ideas are being actively pursued; the dialectic is productive, albeit no synthesis is in sight. We discuss their strengths and weaknesses. The second part of the question can now be much more precisely formulated: thanks to the recent flush of interest in calcium waves in somatic cells, new ideas and new experimental tools are available. The work on somatic cells repays a debt to eggs, where the basic properties of calcium waves were first set out, ten years before they turned up in somatic cells.
Study of Neurotoxic Intracellular Calcium Signalling Triggered by Amyloids