1NYS : Crystal Structure of Activin A Bound to the ECD of ActRIIB P41

  • Thomas B. Thompson (Contributor)
  • Teresa K. Woodruff (Contributor)
  • Theodore S. Jardetzky (Contributor)



Experimental Technique/Method:X-RAY DIFFRACTION
Release Date:2003-04-08
Deposition Date:2003-02-13
Revision Date:2008-04-29#2011-07-13#2017-10-11
Molecular Weight:50666.92
Macromolecule Type:Protein
Residue Count:442
Atom Site Count:2634

The TGF-beta superfamily of ligands and receptors stimulate cellular events in diverse processes ranging from cell fate specification in development to immune suppression. Activins define a major subgroup of TGF-beta ligands that regulate cellular differentiation, proliferation, activation and apoptosis. Activins signal through complexes formed with type I and type II serine/threonine kinase receptors. We have solved the crystal structure of activin A bound to the extracellular domain of a type II receptor, ActRIIB, revealing the details of this interaction. ActRIIB binds to the outer edges of the activin finger regions, with the two receptors juxtaposed in close proximity, in a mode that differs from TGF-beta3 binding to type II receptors. The dimeric activin A structure differs from other known TGF-beta ligand structures, adopting a compact folded-back conformation. The crystal structure of the complex is consistent with recruitment of two type I receptors into a close packed arrangement at the cell surface and suggests that diversity in the conformational arrangements of TGF-beta ligand dimers could influence cellular signaling processes.
Date made available2003

Cite this