Final Activity Report Summary - ZP DOMAIN STRUCTURE (Structure determination of the zona pellucida domain by X-ray crystallography) Fertilisation is a fundamental process necessary for the continuation of mankind and other species. Surprisingly little is known about it on the molecular level. The aim of this project has been to try to understand how the zona pellucida (ZP) coat that surrounds the egg works. The ZP is build up by long filaments of glycoprotein subunits that form a three-dimensional network around the egg. ZP proteins participate in the species-specific recognition of sperm and in blocking more sperms from binding to the egg after the first gamete fusion event. All contain a so-called ZP domain that is responsible for their polymerisation into filaments. We have determined the spatial organisation of the atoms making up the most conserved part of this domain. The results improve our knowledge of fertilisation in general and are crucial for explaining mutations in human ZP domain proteins that cause disease.
