Distribution of FLNa and actin in mature MKs cultured from CD34⁺ blood cells of P3, with isolated thrombocytopenia. (A-B) Mature MKs of a control donor illustrating the concomitant presence of FLNa and actin also seen in extending proplatelets (B). For P3 (C-F), MKs contain FLNa heterogeneously distributed in patches; interestingly, the same distribution is observed for actin filaments (C-D, zones devoid in FLNa). Panel E shows an MK forming PP; this MK has an irregular distribution of FLNa, the MK seems to be partially disrupted. (F) Small MKs with large nuclei show a colocalization of actin and FLNa.