1PNJ:
reference: Solution structure and ligand-binding site of the SH3 domain of the p85 alpha subunit of phosphatidylinositol 3-kinase., Booker GW, Gout I, Downing AK, Driscoll PC, Boyd J, Waterfield MD, Campbell ID, Cell 1993 May 21;73(4):813-22. PMID: 7684655

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