4QPY:
reference: Structures of C1q-like Proteins Reveal Unique Features among the C1q/TNF Superfamily., Ressl S, Vu BK, Vivona S, Martinelli DC, Sudhof TC, Brunger AT, Structure. 2015 Apr 7;23(4):688-99. doi: 10.1016/j.str.2015.01.019. Epub 2015 Mar, 5. PMID: 25752542

This OCA Structure page
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