MSMB Full-Length MS Protein Standard (NP_002434), Labeled with [U- 13C6, 15N4]-L-Arginine and [U- 13C6, 15N2]-L-Lysine, was produced in human 293 cells (HEK293) with fully chemically defined cell culture medium to obtain incorporation efficiency at Creative-Proteomics. The protein encoded by this gene is a member of the immunoglobulin binding factor family. It is synthesized by the epithelial cells of the prostate gland and secreted into the seminal plasma. This protein has inhibin-like activity. It may have a role as an autocrine paracrine factor in uterine, breast and other female reproductive tissues. The expression of the encoded protein is found to be decreased in prostate cancer. Two alternatively spliced transcript variants encoding different isoforms are described for this gene. The use of alternate polyadenylation sites has been found for this gene.