FSH beta

FSH beta is the beta subunit of follicle-stimulating hormone, a pituitary glycoprotein hormone that pairs with the common alpha subunit to form the biologically active FSH heterodimer. The beta chain confers hormone specificity by determining binding to the FSH receptor, a G protein-coupled receptor on ovarian granulosa cells and testicular Sertoli cells. FSH drives follicular development and estradiol production in females and supports spermatogenesis in males. The FSHB gene is expressed in pituitary gonadotropes under GnRH regulation, and loss-of-function mutations cause isolated FSH deficiency with hypogonadism and infertility. Recombinant FSH beta is important for fertility drug development and for studies of glycoprotein hormone assembly.