semenogelin

Semenogelin is a protein that is involved in the formation of a gel matrix that encases ejaculated spermatozoa, preventing capacitation.{{Cite journal|author=de Lamirande E, Lamothe G |title=Levels of semenogelin in human spermatozoa decrease during capacitation: involvement of reactive oxygen species and zinc |journal=Hum Reprod |volume= 25|issue= 7|pages= 1619–1630|date=May 2010 |pmid=20501468 |doi=10.1093/humrep/deq110 |doi-access= }} It blocks capacitation mainly via inhibition of reactive oxygen species (ROS) generation.

Proteolysis by prostate-specific antigen (PSA) breaks down the gel matrix and allows the spermatozoa to move more freely.[https://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=6407 Entrez Gene: SEMG2 semenogelin II] The cleavage products of the semenogelins constitute the main antibacterial components in human seminal plasma.{{cite journal|last=Edström|first=AM|author2=Malm, J |author3=Frohm, B |author4=Martellini, JA |author5=Giwercman, A |author6=Mörgelin, M |author7=Cole, AM |author8=Sørensen, OE |title=The major bactericidal activity of human seminal plasma is zinc-dependent and derived from fragmentation of the semenogelins.|journal=Journal of Immunology|date=Sep 1, 2008|volume=181|issue=5|pages=3413–21|pmid=18714013|pmc=2585754 |doi=10.4049/jimmunol.181.5.3413}}

There are two variants of the semenogelin protein: semenogelin 1 and semenogelin 2.

Semenogelin along with prostate-specific antigen, are commonly tested for during crime scene investigation.