SEMG1

The protein encoded by this gene is the predominant protein in semen. The encoded secreted protein is involved in the formation of a gel matrix that encases ejaculated spermatozoa. This preproprotein is proteolytically processed by the prostate-specific antigen (PSA) protease to generate multiple peptide products that exhibit distinct functions. One of these peptides, SgI-29, is an antimicrobial peptide with antibacterial activity. This proteolysis process also breaks down the gel matrix and allows the spermatozoa to move more freely. This gene and another similar semenogelin gene are present in a gene cluster on chromosome 20.

Full Name

Semenogelin I

Function

Predominant protein in semen. It participates in the formation of a gel matrix entrapping the accessory gland secretions and ejaculated spermatozoa. Fragments of semenogelin and/or fragments of the related proteins may contribute to the activation of progressive sperm movements as the gel-forming proteins are fragmented by KLK3/PSA.
Alpha-inhibin-92 and alpha-inhibin-31, derived from the proteolytic degradation of semenogelin, inhibit the secretion of pituitary follicle-stimulating hormone.

Biological Process

Biological Process antibacterial humoral responseManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process antimicrobial humoral immune response mediated by antimicrobial peptideManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process coagulationManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process inseminationManual Assertion Based On ExperimentTAS:UniProtKB
Biological Process killing of cells of another organismManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process negative regulation of calcium ion importManual Assertion Based On ExperimentIDA:CACAO
Biological Process negative regulation of flagellated sperm motilityManual Assertion Based On ExperimentIDA:CACAO
Biological Process positive regulation of serine-type endopeptidase activityManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process sperm capacitationManual Assertion Based On ExperimentIBA:GO_Central

Cellular Location

Secreted

PTM

Transglutaminase substrate.
Rapidly cleaved after ejaculation by KLK3/PSA, resulting in liquefaction of the semen coagulum and the progressive release of motile spermatozoa.