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Updated: Feb 8, 2026

Kinase Inhibitor Screening In Self-assembled Human Protein Microarrays
Published on: October 23, 2019
A-kinase anchor protein 4 precursor (pro-AKAP4) in human spermatozoa
F Jumeau1,2,3, J Sigala1,2,3, F Dossou-Gbete1,2,3
1EA 4308 - GQG - Gametogenesis and Gamete Quality, University of Lille, Lille, France.
Human pro-AKAP4 is a protein found in sperm that may help improve motility. This study characterized its levels and location in human semen, offering insights for male infertility management.
Area of Science:
- Reproductive Biology
- Sperm Proteomics
- Male Infertility Research
Background:
- A-kinase anchor protein 4 (AKAP4) and its precursor pro-AKAP4 are key proteins in mammalian sperm.
- While AKAP4 is studied in various species, its detailed expression in humans is not well-defined.
Purpose of the Study:
- To precisely characterize human pro-AKAP4, focusing on its localization and expression levels in human spermatozoa and testes.
- To investigate potential associations between pro-AKAP4 levels and semen parameters.
Main Methods:
- Western blotting to assess pro-AKAP4 protein expression levels in sperm extracts and semen samples.
- Immunofluorescence staining and immunogold electron microscopy for pro-AKAP4 localization in spermatozoa and testes.
- Analysis of 77 human semen samples to evaluate pro-AKAP4 levels and correlation with semen parameters.
Main Results:
- A 100-kDa pro-AKAP4 band was detected in human sperm.
- Pro-AKAP4 was localized to the fibrous sheath of the sperm flagellum and in spermatids.
- Significant inter-individual variation in pro-AKAP4 levels was observed in semen samples.
- Pro-AKAP4 levels showed a positive correlation with post-density gradient sperm motility, but not with other standard semen parameters.
Conclusions:
- Human pro-AKAP4 may serve as a reservoir for mature AKAP4, potentially activating an alternative pathway to enhance sperm motility.
- Findings provide new knowledge on pro-AKAP4 in human semen, relevant for managing male infertility.
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