News | Why Sperm Are Streamlined: TSKS Protein Reveals a Key Mechanism
Osaka University Study May Support Male Infertility Diagnosis and Contraceptive Development
The streamlined shape of sperm helps them move through the female reproductive tract and fertilize an egg. Osaka University researchers have identified an important role for the protein **testis-specific serine kinase substrate (TSKS)** in this process.
Published in Proceedings of the National Academy of Sciences (PNAS), the study found that TSKS is essential during **spermiation**, when mature sperm are released from spermatogenic cells. Sperm acquire their streamlined shape by removing cytoplasm, but the molecular mechanism was previously unclear.
How TSKS Works
Using gene editing, researchers created mice with an inactive TSKS gene. Their sperm failed to develop a streamlined shape, resulting in male infertility. The sperm also failed to form two specific membraneless nuage structures: the reticulated body (RB) and chromatoid body remnant (CR).
“RB and CR formation depends on TSKS,” explained co-lead researcher Soojin Park. “Without these structures, sperm cannot remove excess cytoplasm or form the ideal tadpole shape. The accumulated residual cytoplasm causes apoptosis.”
Relevance to Human Sperm and Potential Uses
TSKS is also present in human sperm. The finding offers a new view of the molecular basis of male infertility and may support future diagnostic tests and male contraceptives.
Co-lead researcher Keisuke Shimada said that clarifying TSKS's role improves understanding of male infertility, may optimize diagnosis, and could inform new male contraceptive approaches.
News | Why Sperm Are Streamlined: TSKS Protein Reveals a Key Mechanism
News | Why Sperm Are Streamlined: TSKS Protein Reveals a Key Mechanism
Osaka University Study May Support Male Infertility Diagnosis and Contraceptive Development
The streamlined shape of sperm helps them move through the female reproductive tract and fertilize an egg. Osaka University researchers have identified an important role for the protein **testis-specific serine kinase substrate (TSKS)** in this process.
Published in Proceedings of the National Academy of Sciences (PNAS), the study found that TSKS is essential during **spermiation**, when mature sperm are released from spermatogenic cells. Sperm acquire their streamlined shape by removing cytoplasm, but the molecular mechanism was previously unclear.
How TSKS Works
Using gene editing, researchers created mice with an inactive TSKS gene. Their sperm failed to develop a streamlined shape, resulting in male infertility. The sperm also failed to form two specific membraneless nuage structures: the reticulated body (RB) and chromatoid body remnant (CR).
“RB and CR formation depends on TSKS,” explained co-lead researcher Soojin Park. “Without these structures, sperm cannot remove excess cytoplasm or form the ideal tadpole shape. The accumulated residual cytoplasm causes apoptosis.”
Relevance to Human Sperm and Potential Uses
TSKS is also present in human sperm. The finding offers a new view of the molecular basis of male infertility and may support future diagnostic tests and male contraceptives.
Co-lead researcher Keisuke Shimada said that clarifying TSKS's role improves understanding of male infertility, may optimize diagnosis, and could inform new male contraceptive approaches.
Story source:
Collected online