Androgen-Binding Protein: Carrier proteins produced in the Sertoli cells of the testis, secreted into the seminiferous tubules, and transported via the efferent ducts to the epididymis. They participate in the transport of androgens. Androgen-binding protein has the same amino acid sequence as SEX HORMONE-BINDING GLOBULIN. They differ by their sites of synthesis and post-translational oligosaccharide modifications.Dihydrotestosterone: A potent androgenic metabolite of TESTOSTERONE. It is produced by the action of the enzyme 3-OXO-5-ALPHA-STEROID 4-DEHYDROGENASE.Sertoli Cells: Supporting cells projecting inward from the basement membrane of SEMINIFEROUS TUBULES. They surround and nourish the developing male germ cells and secrete ANDROGEN-BINDING PROTEIN and hormones such as ANTI-MULLERIAN HORMONE. The tight junctions of Sertoli cells with the SPERMATOGONIA and SPERMATOCYTES provide a BLOOD-TESTIS BARRIER.Epididymis: The convoluted cordlike structure attached to the posterior of the TESTIS. Epididymis consists of the head (caput), the body (corpus), and the tail (cauda). A network of ducts leaving the testis joins into a common epididymal tubule proper which provides the transport, storage, and maturation of SPERMATOZOA.Testis: The male gonad containing two functional parts: the SEMINIFEROUS TUBULES for the production and transport of male germ cells (SPERMATOGENESIS) and the interstitial compartment containing LEYDIG CELLS that produce ANDROGENS.Sex Hormone-Binding Globulin: A glycoprotein migrating as a beta-globulin. Its molecular weight, 52,000 or 95,000-115,000, indicates that it exists as a dimer. The protein binds testosterone, dihydrotestosterone, and estradiol in the plasma. Sex hormone-binding protein has the same amino acid sequence as ANDROGEN-BINDING PROTEIN. They differ by their sites of synthesis and post-translational oligosaccharide modifications.Phodopus: A genus of hamsters characterized by small size, very short tail, and short, broad feet with hairy soles.Spermatogenesis: The process of germ cell development in the male from the primordial germ cells, through SPERMATOGONIA; SPERMATOCYTES; SPERMATIDS; to the mature haploid SPERMATOZOA.Testosterone: A potent androgenic steroid and major product secreted by the LEYDIG CELLS of the TESTIS. Its production is stimulated by LUTEINIZING HORMONE from the PITUITARY GLAND. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to DIHYDROTESTOSTERONE or ESTRADIOL.Androgens: Compounds that interact with ANDROGEN RECEPTORS in target tissues to bring about the effects similar to those of TESTOSTERONE. Depending on the target tissues, androgenic effects can be on SEX DIFFERENTIATION; male reproductive organs, SPERMATOGENESIS; secondary male SEX CHARACTERISTICS; LIBIDO; development of muscle mass, strength, and power.Follicle Stimulating Hormone: A major gonadotropin secreted by the adenohypophysis (PITUITARY GLAND, ANTERIOR). Follicle-stimulating hormone stimulates GAMETOGENESIS and the supporting cells such as the ovarian GRANULOSA CELLS, the testicular SERTOLI CELLS, and LEYDIG CELLS. FSH consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Androgen-Insensitivity Syndrome: A disorder of sexual development transmitted as an X-linked recessive trait. These patients have a karyotype of 46,XY with end-organ resistance to androgen due to mutations in the androgen receptor (RECEPTORS, ANDROGEN) gene. Severity of the defect in receptor quantity or quality correlates with their phenotypes. In these genetic males, the phenotypic spectrum ranges from those with normal female external genitalia, through those with genital ambiguity as in Reifenstein Syndrome, to that of a normal male with INFERTILITY.Receptors, Androgen: Proteins, generally found in the CYTOPLASM, that specifically bind ANDROGENS and mediate their cellular actions. The complex of the androgen and receptor migrates to the CELL NUCLEUS where it induces transcription of specific segments of DNA.