| Primary Identifier | IPR034380 | Type | Family |
| Short Name | Testisin |
| description | This entry includes testisin (PRSS21 or esp-1; MEROPS identifier S01.011), also known as tryptase-4 in mice []. Testisin is a serine endopeptidase with predominantly trypsin-like activity []which is bound to the surface of premeiotic spermatocytes via a GPI anchor [, ]. It was first identified in eosinophils but is widely expressed in mononuclear cells and tissues such as testis and prostate []. Knockout of the testisin gene leads to deformed sperm that have reduced motility [], and double knockout of the acrosin and testisin genes reduces fertility in male mice and sperm are unable to cross the zona pellucida of the ovum suggesting a role in fertilization for the peptidases []. Testisin promotes cervical cancer because by binding to the serpin homologue maspin, inhibiting its tumour-suppressing activity []. |
