Androgen binding protein

Androgen-binding protein (ABP) is a glycoprotein (beta-globulin) produced by the Sertoli cells in the seminiferous tubules of the testis that binds specifically to testosterone (T), dihydrotestosterone (DHT), and 17-beta-estradiol. By binding to T and DHT these hormones are made less lipophilic and become concentrated within the luminal fluid of the seminal vesicles. The higher levels of these hormones enable spermatogenesis in the seminiferous tubules and sperm maturation in the epididymis.ABP has the same amino acid sequence as sex hormone-binding globulin (SHBG); the difference is the site of production and the addition of different sugar moieties. ABP contains 403 amino acids resulting in a molecular weight of 44,533. Its gene is located on chromosome 17.
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Androgen /an·dro·gen/ any substance, e.g., testosterone, that promotes masculinization. adrenal androgens the 19-carbon steroids synthesized by [more]Androgen binding protein - Community and Resources