Semenogelin II (SEMG2)

SEMG2 is involved in the formation of a gel matrix that encases ejaculated spermatozoa. Proteolysis by the prostate-specific antigen (PSA) breaks down the gel matrix and allows the spermatozoa to move more freely. The encoded protein is found in lesser abundance than a similar semenogelin protein. The genes encoding these two semenogelin proteins are found in a cluster on chromosome 20.

The transcription units are composed of 3 exons, of which the first encodes the signal peptide, the second encodes secreted protein, and the third contains solely 3-prime, noncoding nucleotides. The nucleotide sequences exhibited a similarity of close to 90% in the exons and greater than 80% in the introns and flanking nucleotides.