Endocrine regulation of gonadotropin glycosylation.
The pituitary gonadotropins--luteinizing hormone and follicle-stimulating hormone--as well as the placental choriogonadotropin belong to the family of glycoprotein hormones. These structurally related hormones, which regulate several major reproductive functions of the body, are heterodimers consisting of a common alpha-subunit noncovalently bound to a beta-subunit. The N- and O-linked oligosaccharide chains of these gonadotropins play an important role in intracellular folding, assembly, secretion, metabolic clearance, and biological activity of the hormone. Gonadotropin glycosylation is a highly complex process; within the gonadotropes it is modulated by a variety of extrapituitary factors of hypothalamic and gonadal origin. In particular, estrogens and androgens appear to regulate terminal sialylation and/or sulfation of the oligosaccharide attachments and hence some functional properties of the gonadotropin molecule determined by these residues, i.e., metabolic clearance and in vivo biopotency. Through these extrapituitary inputs, the anterior pituitary may not only regulate the quantity but also the quality of the gonadotropin signal delivered to the gonads in a given physiologic or pathologic condition.
Ulloa-Aguirre
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Research Unit in Reproductive Medicine, Hospital de Gineco-Obstetricia Luis Castelazo Ayala, Instituto Mexicano del Seguro Social, Mexico City, Mexico. aulloaa@conacty.mx
Maldonado
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Damián-Matsumura
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P
Timossi
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C
D020816:Amino Acid Motifs; D000728:Androgens / Q000494:pharmacology / Q000502:physiology; D000818:Animals; D002240:Carbohydrate Sequence; D002369:Castration; D006063:Chorionic Gonadotropin / Q000737:chemistry / Q000378:metabolism; D004700:Endocrine System Diseases / Q000378:metabolism; D018870:Endoplasmic Reticulum, Rough / Q000378:metabolism; D004967:Estrogens / Q000494:pharmacology / Q000502:physiology; D005260:Female; D005640:Follicle Stimulating Hormone / Q000737:chemistry / Q000378:metabolism; D006031:Glycosylation; D012739:Gonadal Steroid Hormones / Q000494:pharmacology / Q000502:physiology*; D007987:Gonadotropin-Releasing Hormone / Q000502:physiology; D006065:Gonadotropins, Pituitary / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology; D007986:Luteinizing Hormone / Q000737:chemistry / Q000378:metabolism; D008297:Male; D008322:Mammals / Q000502:physiology; D008657:Metabolic Clearance Rate; D008969:Molecular Sequence Data; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D009844:Oligosaccharides / Q000378:metabolism; D010903:Pituitary Gland, Anterior / Q000378:metabolism; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D017510:Protein Folding; D011499:Protein Processing, Post-Translational / Q000502:physiology*; D051381:Rats; D013329:Structure-Activity Relationship; D013972:Thyrotropin / Q000502:physiology; D013973:Thyrotropin-Releasing Hormone / Q000502:physiology
D000728:Androgens; D006063:Chorionic Gonadotropin; D004967:Estrogens; D012739:Gonadal Steroid Hormones; D006065:Gonadotropins, Pituitary; D009844:Oligosaccharides; D007987:Gonadotropin-Releasing Hormone; D013973:Thyrotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin; D019158:N-Acetylneuraminic Acid