Follistatin-like 1/FSTL1 Proteins and Enzymes

Follistatin-like 1 (FSL1) is also known as FSTL1, FRP, Flik, and TSC-36. It is an extracellular glycoprotein belonging to the BM-40/SPARC/Osteonectin family. The protein contains a single cysteine-rich Follistatin module, an extracellular calcium-binding domain, and a region with homology to the von Willebrand Factor C domain. FSL1 was first identified as a TGF-beta-induced protein from a mouse osteoblast cell line.