6MAA:
reference: Crystal structure of the WFIKKN2 follistatin domain reveals insight into how it inhibits growth differentiation factor 8 (GDF8) and GDF11., McCoy JC, Walker RG, Murray NH, Thompson TB, J Biol Chem. 2019 Feb 27. pii: RA118.005831. doi: 10.1074/jbc.RA118.005831. PMID: 30814254

This OCA Structure page
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