Analysis of the proteins associated with platelet detergent resistant membranes

Proteomic studies have facilitated the identification of proteins associated with the detergent‐resistant membrane (DRM) fraction in a variety of cell types. Here, we have undertaken label‐free quantitative (LFQ) proteomic profiling of the proteins associated with detergent‐resistant plasma and internal membranes from resting and activated platelets. One hundred forty‐one proteins were identified and raw data is available via ProteomeXchange with identifier PXD002554. The proteins identified include a myriad of important platelet signaling and trafficking proteins including Rap1b, Src, SNAP‐23, syntaxin‐11, and members of the previously unattributed Ragulator complex. Mean LFQ intensities calculated across three technical replicates for the three biological donors revealed that several important platelet signaling proteins altered their detergent solubility upon activation, including GPIbα, GPIbβ, Src, and 14‐3‐3ζ. Altered detergent solubility for GPIbα, following activation using a variety of platelet agonists, was confirmed by immunoblotting and further coimmunoprecipitation experiments revealed that GPIbα forms a complex with 14‐3‐3ζ that shifts into DRMs following activation. Taken together, proteomic profiling of platelet DRMs allowed greater insight in the complex biology of both DRMs and platelets and will be a useful subproteome to study platelet‐related disease. All MS data have been deposited in the ProteomeXchange with identifier PXD002554 ( http://proteomecentral.proteomexchange.org/dataset/PXD002554 ).