1AGQ:
reference: X-ray structure of glial cell-derived neurotrophic factor at 1.9 A resolution and implications for receptor binding., Eigenbrot C, Gerber N, Nat Struct Biol 1997 Jun;4(6):435-8. PMID: 9187648

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).