Xi'an Frazer Biotech Co., Ltd.

Physical Characters and specifications

FST is a secreted glycoprotein that was first identified as a follicle-stimulating hormone inhibiting substance in ovarian follicular fluid (1, 2). Human FST cDNA encodes a 344 amino acid (aa) protein with a 29 aa signal sequence, an N-terminal atypical TGF binding domain, three FST domains that contain EGF-like and kazal-like motifs, and a highly acidic C-terminal tail. FST is a secreted protein that binds to ligands of the TGF-Beta family and regulates their activity by inhibiting their access to signaling receptors. It was originally discovered as activin antagonists whose activity suppresses expression and secretion of the pituitary hormone FSH (follicle stimulating hormone). In addition to being a natural antagonist, fst can inhibit the activity of other TGF-Beta ligands including BMP-2,-4,-6,-7, Myostatin, GDF-11, and TGF-Beta1. FST is expressed in the pituitary, ovaries, decidual cells of the endometrium, and in some other tissues. Recombinant human FST is a 37.8 kDa protein containing 344 amino acids.
 

FST is fascinating protein that can increase muscle mass beyond natural potential by suppressing myostatin. Scientists first identified fst while examining porcine (re: pig) follicular fluid in the ovaries. 

Fst, specifically FS344, quickly gained popularity in thecommunity as a potential supplement to rapidly increase lean tissue mass. Another protein, fst-related gene (FLRG) acts on similar pathways as FS344 regarding its muscle building properties. Increased lean tissue mass could give a bodybuilder an advantage in a competitive setting and be the differentiating factor between first and second place.

Application