1N4K:
reference: Structure of the inositol 1,4,5-trisphosphate receptor binding core in complex with its ligand., Bosanac I, Alattia JR, Mal TK, Chan J, Talarico S, Tong FK, Tong KI, Yoshikawa F, Furuichi T, Iwai M, Michikawa T, Mikoshiba K, Ikura M, Nature 2002 Dec 12;420(6916):696-700. PMID: 12442173

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