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Medium-throughput Screening Assays for Assessment of Effects on Ca2+-Signaling and Acrosome Reaction in Human Sperm
Published on: March 1, 2019
Beta1 integrin is an adhesion protein for sperm binding to eggs
Keith A Baessler1, Younjoo Lee, Nicole S Sampson
1Biochemistry and Structural Biology Graduate Program, Stony Brook University, Stony Brook, NY 11794, USA.
ACS Chemical Biology
|April 3, 2009
Summary
Beta(1) integrin on egg surfaces enhances sperm attachment rate during mammalian fertilization. Fertilization inhibition occurs via competition for sperm binding, not signaling pathways.
Area of Science:
- Reproductive biology
- Cellular biology
- Molecular mechanisms of fertilization
Background:
- Fertilinbeta-derived polymers are implicated in regulating mammalian fertilization.
- The specific role of beta(1) integrin in fertilization and its interaction with fertilinbeta is not fully understood.
Purpose of the Study:
- To investigate the function of beta(1) integrin in mammalian fertilization.
- To elucidate the mechanism by which fertilinbeta-derived polymers inhibit fertilization.
Main Methods:
- Utilized polymers displaying the Glu-Cys-Asp peptide from the fertilinbeta disintegrin domain.
- Examined the interaction with beta(1) integrin receptor on the egg surface.
- Assessed the impact on sperm binding, attachment, and fusion.
Main Results:
- Fertilinbeta-derived polymers inhibit fertilization by binding to the beta(1) integrin receptor on the egg surface.
- Inhibition is due to competition for sperm binding, not activation of egg signaling pathways.
- Beta(1) integrin enhances the initial rate of sperm attachment but not the total number of sperm that can attach or fuse.
Conclusions:
- Beta(1) integrin plays a crucial role in enhancing initial sperm adhesion to the egg plasma membrane.
- Subsequent sperm attachment and fusion involve additional egg and sperm proteins within the beta(1) integrin complex.
- Fertilization mechanisms differ between wild-type and beta(1) integrin knockout eggs.
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