Patricio Morales¹ and Miguel Llanos²

¹ P. Catholic University of Chile, Faculty of Biological Sciences. P. O. Box 114-D. Santiago, Chile.

²INTA, University of Chile, P. O. Box 138-11. Santiago, Chile.

1. Abstract

2. Introduction

3. The zona pellucida, its composition and role during gamete interaction and fertilization

4. Sperm binding proteins / receptors for the zona pellucida

4.1. Galactosyltransferase

4.2. D-mannosidase

4.3. Protein tyrosine kinase (ZRK)

4.4. Lectin

5. Sperm binding proteins / receptors for the zona pellucida with a role in the acrosome reaction

6. Interaction of spermatozoa with the zona pellucida and development of the acrosome reaction

6.1. Physiological inducers of the acrosome reaction of human sperm

7. Signal transduction mechanisms and the zona pellucida-induced acrosome reaction

7.1. Gi proteins

7.2. Intracellular free calcium

7.3. Polyphosphoinositides

7.4. Adenylyl cyclase activity and cAMP

7.5. Membrane tyrosine kinases

8. Intracellular proteases and the zona pellucida-induced acrosome reaction

9. Cellular biology of human sperm-zona pellucida interaction

9.1. Modulators of sperm-zona pellucida binding

9.1.1. Progesterone

9.1.2. Fucoidin

9.1.3. Sialic acid

9.1.4. D-Mannose

9.1.5. Egg yolk and Milk

9.1.6. Placental protein 14

9.1.7. Gonadotropin hormone-releasing hormone (GnRH)

10. Concluding Remarks

11. References

12. Entire manuscript

Keywords:Human spermatozoa, human zona pellucida, acrosome reaction, second messengers, signal transducing