FcRγ-deficient mice demonstrate unchanged MK differentiation, migration, and spreading. (A) DNA ploidy distribution was analyzed by flow cytometry by staining purified BM-derived mature MKs from WT and FcRγ-deficient mice with propidium iodide and FITC-CD41 antibody. Representative profiles and quantification of the percentage of cells with differing levels of ploidy and the modal ploidy from 3 independent experiments are shown. (B) Purified BM-derived mature MKs from WT and FcRγ knockout (FcRγ KO) were exposed to a SDF1α gradient over 3 hours within the Dunn chamber and the net translocation distance of each cell was measured. (C) Purified BM-derived mature MKs from WT and FcRγ-deficient mice (FcRγ KO) were plated on fibronectin-coated surface for 3 hours. Adherent MKs were fixed, permeabilized and actin fibers stained with rhodamine-phalloidin. Representative images (scale bar = 20μm) and surface area quantification from 4 independent experiments are shown. (D) Purified BM-derived mature MKs from WT and FcRγ-deficient mice (FcRγ KO) were plated on fibronectin (FN) or maintained in suspension in a BSA-coated dish (BSA) for 3 hours. MKs were lysed and WCLs were analyzed by Western blot with MLC-P and MLC antibodies. Blots are representative of 3 independent experiments.