What is Follistatin-344? Activin-binding note

> Research-use notice: This article is educational laboratory context only. It is not medical advice. No dosing, administration, or human-use guidance is provided. BlueNex Labs research-use-only products are not intended for human or veterinary use.

Follistatin-344 is a secreted glycoprotein isoform, not a short synthetic peptide. The 344-residue form includes a heparin-binding region that shorter follistatin isoforms lack. Papers discuss it as a binding protein for activin and other members of the TGF-beta family, including myostatin. There is no follistatin shop SKU on this site. This page does not offer a vial, a price, or a certificate.

Structure

Laboratory context for this isoform usually includes:

• A multi-domain glycoprotein of about 344 amino acids, larger than the research peptides in the catalog

• A heparin-binding sequence that distinguishes follistatin-344 from follistatin-315 in many reviews

• High-affinity binding to activin, which changes how that ligand is available in an assay

• No analytical lot on this website, because the protein is not stocked

A peptide Certificate of Analysis for another compound does not describe follistatin-344.

Mechanisms discussed in research settings

Literature places follistatin in:

• Activin-binding and ligand-sequestration assays

• Myostatin and TGF-beta family pathway maps in cell and animal models

• Comparisons with receptor ligands that do not bind activin, including the growth-factor analog in What is IGF-1 LR3? Receptor-model note

• The same broad muscle-biology literature summarized in Peptides in muscle-biology lab models

Those models measure signaling. They are not instructions, and they are not a reason to invent a product page.

Related notes that do exist

• What is AOD-9604? hGH-fragment research covers a different growth-hormone fragment, also without a catalog vial

• What is CJC-1295 with Ipamorelin? covers secretagogue ligands that *are* listed as research materials

• Metabolic category index: Metabolic Research Peptides, Canada

RUO

Research-use only. Not for human or veterinary use. No administration guidance is provided.