The clathrin adaptor AP2 is phosphorylated at a single site (Thr156) of its µ2 subunit. To gain insight how phosphorylation influences the interactome of AP2, we used human RPE cells which that were treated with LP-935509, an inhibitor of the adaptor-associated kinase AAK1. Kinase inhibition and loss of µ2 phosphorylation was verified with phospho-specific antibodies in westernblots of total cell extracts. We then used SILAC labelled cells and immune-isolated AP-2 and subjected bound proteins to mass spectrometry to identify all bound proteins and to determine phosphorylation-dependent changes in the interactome.