Serine protease 55 (PRSS55)

Serine protease 55 (PRSS55) is a membrane-anchored chymotrypsin-like serine protease predominantly expressed in the testis, with expression restricted mainly to Leydig and Sertoli cells, and especially in spermatids and epididymal spermatozoa[5][1]. PRSS55 is implicated in male reproductive biology, where it is essential for the structural differentiation and motility of sperm, likely functioning by proteolytically activating structural proteins such as type II muscle myosin and by maintaining the stability of sperm membrane proteins like ADAM3[1][4][2]. Knockout mouse models show that loss of PRSS55 leads to severe male infertility, with sperm exhibiting abnormal morphology, defective energy metabolism, impaired migration through the female reproductive tract, and reduced ability to bind the oocyte zona pellucida[1][2][4][3]. PRSS55 is therefore considered a critical factor in spermiogenesis and male fertility. While PRSS55 does not currently have known interacting drugs or direct safety concerns, its essential role in reproduction makes it a potential biomarker and therapeutic target in the context of male infertility[1][4][5].

Other names

CT153T-SP1TSP1UNQ9391Testis serine protease 1Protease, serine 55

Proteolytic activation of substrate proteins such as type II muscle myosins and regulation of sperm membrane protein ADAM3 stability