A typical mammalian egg is surrounded by an outer layer of about 3,000 cumulus cells embedded in an extracellular matrix rich in hyaluronic acid. A current, widely proposed model is that the fertilizing sperm, while it is acrosome intact, passes through the cumulus cell layer and binds to the egg zona pellucida. This current model lacks a well-supported explanation for how sperm penetrate the cumulus layer. We report that the sperm protein PH-20 has a hyaluronidase activity and is present on the plasma membrane of mouse and human sperm. Brief treatment with purified, recombinant PH-20 can release all the cumulus cells surrounding mouse eggs. Acrosome intact mouse sperm incubated with anti-PH-20 antibodies can not pass through the cumulus layer and thus can not reach the zona pellucida. These results, indicating that PH-20 enables acrosome intact sperm to penetrate the cumulus barrier, reveal a mechanism for cumulus penetration, and thus provide the missing element in the current model.
Article|
June 01 1994
A hyaluronidase activity of the sperm plasma membrane protein PH-20 enables sperm to penetrate the cumulus cell layer surrounding the egg.
Y Lin,
Y Lin
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
Search for other works by this author on:
K Mahan,
K Mahan
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
Search for other works by this author on:
W F Lathrop,
W F Lathrop
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
Search for other works by this author on:
D G Myles,
D G Myles
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
Search for other works by this author on:
P Primakoff
P Primakoff
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
Search for other works by this author on:
Y Lin
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
K Mahan
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
W F Lathrop
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
D G Myles
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
P Primakoff
Department of Physiology, University of Connecticut Health Center, Farmington 06030.
Online ISSN: 1540-8140
Print ISSN: 0021-9525
J Cell Biol (1994) 125 (5): 1157–1163.
Citation
Y Lin, K Mahan, W F Lathrop, D G Myles, P Primakoff; A hyaluronidase activity of the sperm plasma membrane protein PH-20 enables sperm to penetrate the cumulus cell layer surrounding the egg.. J Cell Biol 1 June 1994; 125 (5): 1157–1163. doi: https://doi.org/10.1083/jcb.125.5.1157
Download citation file:
