1R1K:
reference: Structural adaptability in the ligand-binding pocket of the ecdysone hormone receptor., Billas IM, Iwema T, Garnier JM, Mitschler A, Rochel N, Moras D, Nature 2003 Nov 6;426(6962):91-6. Epub 2003 Nov 2. PMID: 14595375

This OCA Structure page
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