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Using an Extracellular Flux Analyzer to Measure Changes in Glycolysis and Oxidative Phosphorylation during Mouse Sperm Capacitation
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CDC42 drives RHOA activity and actin polymerization during capacitation
Tania Reyes-Miguel1, Ana L Roa-Espitia1, Rafael Baltiérrez-Hoyos2
1Departamento de Biología Celular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, San Pedro Zacatenco, Gustavo A. Madero, México City, México.
Reproduction (Cambridge, England)
|June 23, 2020
Summary
CDC42 and RHOA proteins are crucial for mammalian sperm capacitation and the acrosome reaction, regulating actin polymerization. CDC42 activation initiates this process, with RHOA activation following, highlighting CDC42
Area of Science:
- Reproductive Biology
- Cell Biology
- Sperm Physiology
Background:
- Mammalian sperm capacitation is essential for fertilization.
- Actin polymerization is critical for sperm-oolemma adhesion and fusion during fertilization.
- RHO proteins CDC42 and RHOA regulate actin polymerization, but their roles in sperm capacitation are unclear.
Purpose of the Study:
- To investigate the roles of CDC42 and RHOA in sperm capacitation and the acrosome reaction.
- To elucidate the relationship between CDC42, RHOA, and actin polymerization in guinea pig sperm.
Main Methods:
- Utilized guinea pig sperm model.
- Inhibited CDC42 and RHOA activities.
- Assessed actin polymerization kinetics.
- Monitored capacitation and acrosome reaction progression.
Main Results:
- Inhibition of CDC42 and RHOA differentially affected actin polymerization, capacitation, and acrosome reaction kinetics.
- CDC42 activation is required for initiating actin polymerization and RHOA activation.
- RHOA activation follows and depends on maximal CDC42 activity.
- RHOA's role in capacitation and acrosome reaction is independent of ROCK1.
Conclusions:
- CDC42 and RHOA play distinct roles in sperm capacitation and the acrosome reaction.
- CDC42 activation is a prerequisite for RHOA-mediated effects on actin polymerization.
- CDC42 appears to have a dominant role in these processes.
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