The mechanism of generating and sensing electrical signals flowing through the human body has been studied for a long time. It has been known that a molecule called a "voltage-gated ion channel" senses an electrical signal and causes the flow of ions into the cell.Also, such an electrical signal sensing system appears to be common to all cells.

　So far, the research group has identified a molecule called "voltage-dependent phosphatase (VSP)".Unlike voltage-gated ion channels, VSP exhibits an enzymatic activity called "phosphatase activity" and alters the amount of an important bioactive molecule called "inositol phospholipid PIP2".In addition, although it has been shown in mice that VSP may be present in sperm, it was unclear how it is involved in sperm function because it is difficult to analyze due to technical restrictions.

　This time, the research group found that VSP is present in the flagella of sperm using a mouse and using a unique technology. In sperm deficient in VSP, the amount and distribution of this "inositol phospholipid" changed, resulting in abnormal sperm motility.Therefore, it was found that sperm convert their electrical signals into enzyme activity and control their motility.

　This discovery suggests that there may still be an unknown mechanism in the electrical signals of living organisms, which many researchers have been paying attention to for more than a century.Since sperm's unique electrical signal is important for sperm's motor function, it is expected to be applied to infertility treatment.

Paper information:[Proc. Natl. Acad. Sci. USA] Polarized PtdIns (4,5) P2 distribution mediated by a voltage-sensing phosphatase (VSP) regulates sperm motility