1AQG:
reference: Light-activated rhodopsin induces structural binding motif in G protein alpha subunit., Kisselev OG, Kao J, Ponder JW, Fann YC, Gautam N, Marshall GR, Proc Natl Acad Sci U S A 1998 Apr 14;95(8):4270-5. PMID: 9539726

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