The regulatory protein 14-3-3β binds to the IQ motifs of myosin-IC independent of phosphorylation.

ABSTRACT: Myosin-IC (Myo1c) has been proposed to function in delivery of glucose transporter type 4 (GLUT4)-containing vesicles to the plasma membrane in response to insulin stimulation. Current evidence suggests that, upon insulin stimulation, Myo1c is phosphorylated at Ser⁷⁰¹, leading to binding of the signaling protein 14-3-3β. Biochemical and functional details of the Myo1c-14-3-3β interaction have yet to be described. Using recombinantly expressed proteins and mass spectrometry-based analyses to monitor Myo1c phosphorylation, along with pulldown, fluorescence binding, and additional biochemical assays, we show here that 14-3-3β is a dimer and, consistent with previous work, that it binds to Myo1c in the presence of calcium. This interaction was associated with dissociation of calmodu

SUBMITTER: Ji HH 

PROVIDER: S-EPMC7086031 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature