About Careers Internship MedBlogs Contact us
Medindia LOGIN REGISTER
Advertisement

How Sperm Gets into the Zona Pellucida

by Dr. Enozia Vakil on June 16, 2014 at 10:10 PM
Font : A-A+

 How Sperm Gets into the Zona Pellucida

The sperm has to bind and bore through an outer layer called the zona pellucida before it can fertilize an egg. Despite decades of research, some of the biological mechanisms behind this process remain unclear. A study in The Journal of Cell Biology now identifies the protein in the zona pellucida that sperm latch onto.

The zona pellucida protects the egg and the early embryo before implantation. Its structure seems simple—in humans it contains four kinds of glycoproteins, and in mice it only contains three. But researchers haven't been able to identify the sperm's binding partner in the layer, although their suspicions have fallen on two of the glycoproteins, ZP2 and ZP3.

Advertisement

To find out more, Jurrien Dean and colleagues from the National Institute of Diabetes and Digestive and Kidney Diseases engineered mice to produce various combinations of human and mouse zona pellucida glycoproteins. Mouse sperm didn't bind to the zona pellucida if it was missing ZP2, and female mice lacking the protein were sterile. The researchers also found that sperm couldn't latch onto eggs if ZP2 was missing a key region at the beginning of the protein. This result jibes with a previous finding that fertilization triggers the release of an enzyme that severs ZP2 in this region, thus preventing additional sperm from attaching to the zona pellucida.

The team also tested the binding of human sperm to mouse eggs surrounded by a zona pellucida harboring human glycoproteins. Human sperm adhered to the mouse zona pellucida if it contained human ZP2 but not if it carried human ZP3, confirming the importance of ZP2.



Source: Eurekalert
Advertisement

Advertisement
News A-Z
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
What's New on Medindia
Are Menopause Symptoms Troubling You?: Try these Options
Vaccination  And Counter  Measures Against  Monkeypox
Indian Railways Special Concession on Health Grounds
View all
Recommended Reading
News Archive
Date
Category
News Category

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
Genetics of Male Infertility Artificial Insemination Varicocele Premature Ejaculation Sex Numbers 

Most Popular on Medindia

Blood Donation - Recipients Pregnancy Confirmation Calculator Noscaphene (Noscapine) Find a Doctor Blood Pressure Calculator Drug Side Effects Calculator Vent Forte (Theophylline) Iron Intake Calculator Diaphragmatic Hernia Blood - Sugar Chart

Disclaimer - All information and content on this site are for information and educational purposes only. The information should not be used for either diagnosis or treatment or both for any health related problem or disease. Always seek the advice of a qualified physician for medical diagnosis and treatment. Full Disclaimer

© All Rights Reserved 1997 - 2022

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use
open close
ASK A DOCTOR ONLINE