Question

What happens when the sperms fuse with the egg plasma membrane?

Answer 1

Fusion of sperms with the egg plasma membrane:

1. Sperm fusion is a membrane fusion event required for the propagation of sexually reproductive organisms.
2. In gamete fusion, as in other fusion events, such as fusion between viral cells and endoplasmic reticulum, membrane fusion is a two-step process.
3. Bi-membrane attachment across cell surface molecules is followed by the physical fusion of plasma membrane lipids.
4. In the event of a sperm fusing with the egg plasma membrane, it induces a local increase in the cytosolic calcium ion.
5. This propagates through the cell in a wave. In a few mammalian eggs, the initial elevation in the calcium ion is followed by a long calcium oscillation.
6. There is testimony that these calcium oscillations or waves are caused by a protein that is introduced into the egg by sperms.
7. However, the nature of the protein is not known.