Semenogelin is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

that is involved in the formation of a gel matrix that encases ejaculated spermatozoa, preventing capacitation. It blocks capacitation mainly via inhibition of

reactive oxygen species In chemistry, reactive oxygen species (ROS) are highly reactive chemicals formed from diatomic oxygen (). Examples of ROS include peroxides, superoxide, hydroxyl radical, singlet oxygen, and alpha-oxygen. The reduction of molecular oxygen () p ...

(ROS) generation. Proteolysis by

prostate-specific antigen Prostate-specific antigen (PSA), also known as gamma-seminoprotein or kallikrein-3 (KLK3), P-30 antigen, is a glycoprotein enzyme encoded in humans by the ''KLK3'' gene. PSA is a member of the kallikrein-related peptidase family and is secreted b ...

(PSA) breaks down the gel matrix and allows the spermatozoa to move more freely. The cleavage products of the semenogelins constitute the main antibacterial components in human seminal plasma. There are two variants of the semenogelin protein:

semenogelin 1 Semenogelin-1 is a protein that in humans is encoded by the ''SEMG1'' gene. 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 spe ...

and

semenogelin 2 Semenogelin-2 is a protein that in humans is encoded by the ''SEMG2'' gene. The secreted protein encoded by this gene is involved in the formation of a gel matrix that encases ejaculated spermatozoa. Proteolysis by the prostate-specific antigen ( ...

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

References

{{Reflist Proteins