A novel calmodulin-β-PIX interaction and its implication in receptor tyrosine kinase regulation

► CaM binds directly to β-PIX in a Ca2 +-dependent manner. ► Fluorescence measurements and ITC show a KD ≤ 10 μM for the CaM-β-PIX interaction. ► CaM is essential for interaction of β-PIX with Cbl, to form a multi-protein complex. ► Cbl-mediated RTK ubiquitination is Ca2 +/CaM dependent.