Biomaterial Database

Interactions between mouse ZP2 glycoprotein and proacrosin; a mechanism for secondary binding of sperm to the zona pellucida during fertilization. 2001

E Howes, and J C Pascall, and W Engel, and R Jones

Signalling Programme, The Babraham Institute, Cambridge CB2 4AT, UK.

The mouse zona pellucida glycoprotein, mZP2, is thought to be the secondary receptor on eggs for retention of acrosome-reacted sperm during fertilization. Here, we present evidence that one of its complementary binding proteins on sperm is proacrosin/acrosin. mZP2 binds to proacrosin null sperm considerably less effectively than to wild-type sperm. Binding is mediated by a strong ionic interaction between polysulphate groups on mZP2 and basic residues on an internal proacrosin peptide. The stereochemistry of both sulphate groups and basic amino acids determines the specificity of binding. Structurally relevant sulphated polymers and suramin, a polysulphonated anticancer drug, compete with mZP2 for complementary binding sites on proacrosin/acrosin in solid-phase binding assays. The same competitors also displace attached sperm from the zona pellucida of eggs in an in vitro fertilization system. This combination of genetic, biochemical and functional data supports the hypothesis that mZP2-proacrosin interactions are important for retention of acrosome-reacted sperm on the egg surface during fertilization. Safe mimetics of suramin have potential as non-steroidal antifertility agents.

UI	MeSH Term	Description	Entries
D007457	Iodine Radioisotopes	Unstable isotopes of iodine that decay or disintegrate emitting radiation. I atoms with atomic weights 117-139, except I 127, are radioactive iodine isotopes.	Radioisotopes, Iodine
D008297	Male		Males
D008562	Membrane Glycoproteins	Glycoproteins found on the membrane or surface of cells.	Cell Surface Glycoproteins,Surface Glycoproteins,Cell Surface Glycoprotein,Membrane Glycoprotein,Surface Glycoprotein,Glycoprotein, Cell Surface,Glycoprotein, Membrane,Glycoprotein, Surface,Glycoproteins, Cell Surface,Glycoproteins, Membrane,Glycoproteins, Surface,Surface Glycoprotein, Cell,Surface Glycoproteins, Cell
D008822	Mice, Transgenic	Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.	Transgenic Mice,Founder Mice, Transgenic,Mouse, Founder, Transgenic,Mouse, Transgenic,Mice, Transgenic Founder,Transgenic Founder Mice,Transgenic Mouse
D010063	Ovum	A mature haploid female germ cell extruded from the OVARY at OVULATION.	Egg,Egg, Unfertilized,Ova,Eggs, Unfertilized,Unfertilized Egg,Unfertilized Eggs
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell
D004527	Egg Proteins	Proteins which are found in eggs (OVA) from any species.	Egg Protein,Egg Shell Protein,Egg Shell Proteins,Egg White Protein,Egg White Proteins,Egg Yolk Protein,Egg Yolk Proteins,Ovum Protein,Ovum Proteins,Yolk Protein,Yolk Proteins,Protein, Egg,Protein, Egg Shell,Protein, Egg White,Protein, Egg Yolk,Protein, Ovum,Protein, Yolk,Proteins, Egg,Proteins, Egg Shell,Proteins, Egg White,Proteins, Egg Yolk,Proteins, Ovum,Proteins, Yolk,Shell Protein, Egg,Shell Proteins, Egg,White Protein, Egg,White Proteins, Egg,Yolk Protein, Egg,Yolk Proteins, Egg
D004792	Enzyme Precursors	Physiologically inactive substances that can be converted to active enzymes.	Enzyme Precursor,Proenzyme,Proenzymes,Zymogen,Zymogens,Precursor, Enzyme,Precursors, Enzyme
D005260	Female		Females