2b0u
From Proteopedia
The Structure of the Follistatin:Activin Complex
Contents |
Overview
TGF-beta ligands stimulate diverse cellular differentiation and growth responses by signaling through type I and II receptors. Ligand antagonists, such as follistatin, block signaling and are essential regulators of physiological responses. Here we report the structure of activin A, a TGF-beta ligand, bound to the high-affinity antagonist follistatin. Two follistatin molecules encircle activin, neutralizing the ligand by burying one-third of its residues and its receptor binding sites. Previous studies have suggested that type I receptor binding would not be blocked by follistatin, but the crystal structure reveals that the follistatin N-terminal domain has an unexpected fold that mimics a universal type I receptor motif and occupies this receptor binding site. The formation of follistatin:BMP:type I receptor complexes can be explained by the stoichiometric and geometric arrangement of the activin:follistatin complex. The mode of ligand binding by follistatin has important implications for its ability to neutralize homo- and heterodimeric ligands of this growth factor family.
Disease
Known disease associated with this structure: Polycystic ovary syndrome OMIM:[136470]
About this Structure
2B0U is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
The structure of the follistatin:activin complex reveals antagonism of both type I and type II receptor binding., Thompson TB, Lerch TF, Cook RW, Woodruff TK, Jardetzky TS, Dev Cell. 2005 Oct;9(4):535-43. PMID:16198295 Page seeded by OCA on Sat May 3 19:42:54 2008
