File:Degradation of oocytes by sperm proteasomes.png

Degradation of Intact Oocyte Zonae by Isolated Sperm Proteasomes.

Maturing ova were incubated with purified sperm proteasomes for four hours with non-activated (a, b) or heat activated (c, d) sperm proteosomes, fertilized in vitro, and processed with anti-ZPC antibody (red), DNA stain DAPI (blue) and acrosomal shroud marker - lectin PNA-FITC (green). Note sperm detachment, and a striking abrasion and loosening of the zona in the active proteasome-treated ova (c, d). Preincubation with active proteasomes coincides with a reduced rate of polyspermic fertilization after IVF (e, f). IVF experiment was repeated three times, with total oocyte numbers shown above each column in panel f. Control (g; left) and proteasome treated (g; right) ova were also processed with anti-ZPC antibody immediately at the end of the 4 h coincubation, causing a pattern of zona digestion and abrasion (right zona) similar to that seen in IVF ova pre-treated with active proteasomes.

Citation: Zimmerman SW, Manandhar G, Yi Y-J, Gupta SK, Sutovsky M, et al. (2011) Sperm Proteasomes Degrade Sperm Receptor on the Egg Zona Pellucida during Mammalian Fertilization. PLoS ONE 6(2): e17256. doi:10.1371/journal.pone.0017256

Editor: Vladimir Uversky, University of South Florida College of Medicine, United States of America

Received: July 28, 2010; Accepted: January 27, 2011; Published: February 23, 2011

Copyright: © 2011 Zimmerman et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.