Analysis Note

The biological activity is measured by its ability to neutralize activin-induced bioactivity on K562 cells (erythroid differentiation).

Application

FST (follistatin) has been used for trophoblast fusion assay and the measure of hCG (human chorionic gonadotropin) concentration in hormone assays. It is also suitable for the development of chondrocytes from hESc (human embryonic stem cells) by a new 3-Stage directed differentiation protocol (DDP).

Biochem/physiol Actions

FST (follistatin) binds to and regulates activins, which in turn are TGF (transforming growth factor)-β superfamily members. The expression level of FST and its binding partner activin A is elevated in inflammatory disorders. The activin A-follistatin system plays an essential role in the modulation of glucose and lipid metabolism, which might have an overall effect on fetal growth. In adipose tissue, it facilitates the adipogenic differentiation of progenitor cells.

High-affinity activin-binding protein that can act as an activin antagonist.

General description

FST (follistatin) is an activin-binding protein, and exists in two isoforms due to alternate splicing, FS288 and FS315. It is a glycoprotein with a single chain, and acts as an activin antagonist. It has a high level of expression in fetal membranes and placenta.

Packaging

25 µg in glass insert

Physical form

Lyophilized from a solution in 30% acetonitrile and 0.1% trifluoroacetic acid containing 1.25 mg bovine serum albumin.