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Updated: Jan 25, 2026
08:58
Fluorimetric Techniques for the Assessment of Sperm Membranes
Published on: November 28, 2018
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Dimorphic sperm formation by Sex-lethal.
Hiroki Sakai1, Hiroyuki Oshima2, Kodai Yuri3
1Division of Evolutionary Developmental Biology, National Institute for Basic Biology, Myodaiji, 444-8585 Okazaki, Japan.
Summary
The Sex-lethal (Sxl) gene is crucial for the development of non-fertile apyrene sperm in Bombyx mori moths. These apyrene sperm are essential for the fertilization process involving fertile eupyrene sperm.
Area of Science:
- Developmental Biology
- Genetics
- Entomology
Background:
- Master sex-determination genes exhibit high divergence across species.
- The Sex-lethal (Sxl) gene is essential for female germline development in Drosophila melanogaster.
- Sxl's sex-determination function is not conserved across different insect orders.
Purpose of the Study:
- Investigate the function of the Sex-lethal (Sxl) gene in the lepidopteran insect Bombyx mori.
- Determine Sxl's role in spermatogenesis, specifically in the context of eupyrene and apyrene sperm production and function.
Main Methods:
- Utilized genetic analyses with Sxl mutants in Bombyx mori.
- Observed and analyzed sperm morphogenesis and fertilization processes in Sxl mutants.
Main Results:
- Sxl is indispensable for the proper morphogenesis of apyrene sperm in Bombyx mori.
- Apyrene sperm are necessary for the migration of eupyrene sperm, ensuring successful fertilization.
- Sxl plays critical roles in spermatogenesis in Bombyx mori, contrasting with its role in oogenesis in Drosophila.
Conclusions:
- The Sex-lethal (Sxl) gene has a vital role in spermatogenesis in Bombyx mori, specifically in apyrene sperm development and function.
- The findings suggest that the ancestral function of Sxl may be related to broader germline development, rather than solely sex determination.
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