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05:44
Medium-throughput Screening Assays for Assessment of Effects on Ca2+-Signaling and Acrosome Reaction in Human Sperm
Published on: March 1, 2019
Acrosome formation-associated factor is involved in fertilization
Xiao-Qian Hu1, Shao-Yang Ji, Yin-Chuan Li
1The State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, People's Republic of China.
Fertility and Sterility
|March 17, 2009
Summary
A novel factor, acrosome formation-associated factor (Afaf), regulates sperm function. Afaf impacts acrosomal exocytosis and endosomal trafficking, crucial for fertilization success.
Area of Science:
- Reproductive Biology
- Cell Biology
- Molecular Biology
Background:
- Sperm function is critical for successful fertilization.
- Acrosomal exocytosis and endosomal trafficking are key cellular processes involved in sperm function.
- The molecular mechanisms regulating these processes are not fully understood.
Purpose of the Study:
- To investigate the role of a novel factor, acrosome formation-associated factor (Afaf), in regulating acrosomal exocytosis and endosomal trafficking.
- To determine the impact of Afaf on sperm fertilization capabilities.
Main Methods:
- Controlled laboratory study using ICR mice.
- Sperm penetration assays and in vitro fertilization experiments.
- Analysis of acrosomal exocytosis, calcium signaling, and endosomal trafficking (Transferrin uptake).
- Investigated interaction between Afaf and SNAP25 using colocalization and coimmunoprecipitation.
- RNA interference (RNAi) was used to modulate Afaf levels.
Main Results:
- Afaf antibodies significantly inhibited sperm penetration and in vitro fertilization rates.
- Afaf is involved in calcium-triggered acrosomal exocytosis, acting upstream of calcium efflux.
- Afaf interacts with SNAP25, a protein vital for exocytosis and endosomal trafficking.
- Afaf down-regulates Transferrin endocytosis in HeLa cells, an effect reversible by RNAi.
Conclusions:
- Acrosome formation-associated factor (Afaf) plays a significant role in membrane trafficking during acrosome formation.
- Afaf is implicated in the regulation of acrosomal exocytosis and endosomal trafficking.
- Afaf is a potential key player in the fertilization process.
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