{"id":70719,"date":"2026-05-12T09:49:37","date_gmt":"2026-05-12T09:49:37","guid":{"rendered":"https:\/\/medsbase.com\/?post_type=product&p=70719"},"modified":"2026-05-21T07:14:10","modified_gmt":"2026-05-21T07:14:10","slug":"follistatin-344","status":"publish","type":"product","link":"https:\/\/medsbase.com\/nl\/follistatin-344\/","title":{"rendered":"Follistatin 344"},"content":{"rendered":"

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Quick Answer \u2014 What is Follistatin 344?<\/h3>\n

Follistatin 344<\/strong> (FST-344) is a 344-amino-acid recombinant glycoprotein and the longer of the two principal splice isoforms of human follistatin. It is the canonical endogenous antagonist of myostatin (GDF-8) and activin, used in published research investigating muscle hypertrophy, sarcopenia, muscular dystrophy preclinical models, and the activin\/myostatin signalling axis. Supplied in 1\u00a0mg lyophilized vials for laboratory research use only.<\/p>\n<\/div>\n

Wat u krijgt bij MedsBase:<\/strong> Research-grade lyophilized recombinant protein \u00b7 HPLC \u226595% purity (COA on request) \u00b7 Discreet temperature-stable packaging \u00b7 Worldwide peptide courier \u00b7 1,400+ verified klantbeoordelingen<\/a><\/div>\n

\ud83d\udce6 Elke bestelling is gedekt door onze Reshipment Assurance Policy<\/strong><\/a> \u2014 als uw pakket niet binnen 20 werkdagen arriveert, sturen wij het opnieuw.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Specificatie<\/th>\nDetail<\/th>\n<\/tr>\n<\/thead>\n
CAS-nummer<\/strong><\/td>\n80449-31-6 (follistatin)<\/td>\n<\/tr>\n
Type<\/strong><\/td>\nRecombinant glycoprotein (344-amino-acid FST-344 splice isoform of human follistatin)<\/td>\n<\/tr>\n
Moleculair gewicht<\/strong><\/td>\n~37\u00a0kDa (mature glycosylated form; ~38\u201342\u00a0kDa observed range on SDS-PAGE depending on glycosylation state)<\/td>\n<\/tr>\n
Structure<\/strong><\/td>\nN-terminal heparin-binding domain followed by three follistatin domains (FSD1, FSD2, FSD3) each containing an EGF-like and a Kazal-like subdomain; cysteine-rich, multiple intramolecular disulfide bonds<\/td>\n<\/tr>\n
Form<\/strong><\/td>\nLyophilized recombinant protein (white to off-white)<\/td>\n<\/tr>\n
Zuiverheid<\/strong><\/td>\n\u226595% (HPLC verified, COA on request)<\/td>\n<\/tr>\n
Opslag<\/strong><\/td>\nLyophilized: 2\u20138\u00a0\u00b0C (refrigerator) for working stock; \u221220\u00a0\u00b0C for long-term storage of unopened vials. Reconstituted: 2\u20138\u00a0\u00b0C, use within ~30 days. Protect from light. Do not freeze\u2013thaw the reconstituted solution \u2014 recombinant proteins are particularly sensitive to freeze-thaw denaturation.<\/td>\n<\/tr>\n
Oplosbaarheid<\/strong><\/td>\nBacteriostatic water (recommended) or sterile water for shorter use windows. Carrier protein (BSA, 0.1%) optional for working dilutions to minimise adsorption losses.<\/td>\n<\/tr>\n
Onderzoeksgebruik<\/strong><\/td>\nAlleen voor laboratoriumonderzoek. Niet voor humaan of veterinair diagnostisch of therapeutisch gebruik.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

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What Is Follistatin 344?<\/h2>\n

Follistatin 344<\/strong> (often abbreviated FST-344) is a recombinant 344-amino-acid glycoprotein and the longer of the two principal physiological splice isoforms of human follistatin \u2014 the other being FST-288, a shorter 288-amino-acid membrane-bound form. Endogenous follistatin was first isolated in 1987 from porcine ovarian follicular fluid by Esch et al. (PNAS) and Robertson et al. (Biochem Biophys Res Commun) as a factor that selectively inhibits follicle-stimulating hormone (FSH) secretion, which gave the protein its name. The mechanistic role \u2014 high-affinity binding and neutralisation of activin and myostatin \u2014 was characterised over the subsequent decade.<\/p>\n

FST-344 is a circulating, secreted isoform with a heparin-binding N-terminal domain followed by three cysteine-rich follistatin domains (FSD1, FSD2, FSD3) that together form the activin- and myostatin-binding surface. The recombinant 344-residue chain has a mature mass of approximately 37\u00a0kDa, with apparent molecular weight on SDS-PAGE varying between 38 and 42\u00a0kDa depending on the glycosylation state of the recombinant expression system. CAS number 80449-31-6. The protein is supplied as a high-purity lyophilized powder for reconstitution with bacteriostatic water. Follistatin is not approved<\/strong> by the FDA, EMA, MHRA, or any other major regulator for human therapeutic use. The research-grade follistatin 344 sold here is supplied uitsluitend voor laboratoriumonderzoek<\/strong> and is not intended for human or veterinary administration. For related anabolic and growth-axis research, see our IGF-1 LR3<\/a> product page.<\/p>\n

Mechanism of Action \u2014 Myostatin and Activin Pathway Antagonism<\/h2>\n

What makes follistatin 344 mechanistically unique among muscle-research proteins is its multi-target binding profile<\/strong> across the TGF-\u03b2 superfamily \u2014 each ligand-binding event contributing to the observed hypertrophic and growth-modulatory phenotype in published research:<\/p>\n