Zinc is a key regulator of the sperm-specific K(+) channel (Slo3) function.

Intracellular Zn 2+ directly inhibits mouse Slo3 potassium channels in a dose-dependent manner at micromolar concentrations, with slow dissociation, during sperm capacitation.

• Why it matters: Understanding how zinc regulates sperm ion channels is crucial because Slo3 activity influences sperm hyperpolarization and fertility, yet the mechanisms of zinc’s role remain unclear.
• What they did: The study combined electrophysiology, molecular dynamics simulations, and expression in Xenopus oocytes to show that sperm-enriched Zn 2+ modulates Slo3 channels by binding to specific amino acid residues, revealing slow dissociation kinetics.
• The result: These findings highlight intracellular zinc as a key regulator of Slo3 function, suggesting zinc dynamics are important for ion channel regulation during sperm capacitation and fertility.