PACSIN2 localization in bone marrow MKs requires FlnA. Super-resolution SIM of PACSIN2 (red), CD41 (green), and DAPI (blue) in fixed (A) midstage and (B) mature matrigel-cultured WT mouse MKs. Arrowhead indicates tubule-associated PACSIN2 concentration. Scale bars represent 2 and 3 µm, respectively. (C) Confocal microscopy of PACSIN2 (green) and β-tubulin (red) in fixed cultured WT (upper) and Flna-null mouse (lower) bone marrow MKs. Scale bar represents 20 µm. (D) Confocal microscopy of EGFP-PACSIN2 WT or mutant P180A (green), and CD41 (red) in fixed control and Flna-null cultured cytospun bone marrow MKs, as indicated. Scale bar represents 20 µm. (E) Percentage of transfected MKs with defined EGFP-PACSIN2⁺ membrane tubulation was scored. Total MKs scored were 46 WT and 18 Flna null.