FSTL1

Follistatin-related protein 1 is a is_associated_with::protein that in humans is encoded by the FSTL1 is_associated_with::gene.

Structure
This gene encodes a protein with similarity to is_associated_with::follistatin, an is_associated_with::activin-binding protein. It contains an FS module (a follistatin-like sequence containing 10 conserved cysteine residues), a is_associated_with::Kazal-type serine protease inhibitor domain, 2 is_associated_with::EF hand domains, and a is_associated_with::Von Willebrand factor type C domain.

Clinical significance
This gene product is thought to be an autoantigen associated with is_associated_with::rheumatoid arthritis.

FSTL1 up-regulates proinflammatory mediators important in the pathology of arthritis, and serum levels of FSTL1 correlate with severity of arthritis.