F-actin is associated with NMIIB and Tmod1 in mouse FL enucleating erythroblasts. (A) Extended-focus projections of confocal Z-stacks of mouse FL erythroblasts at various stages of enucleation immunostained for NMIIB and Ter119, phalloidin for F-actin, and Hoechst for nuclei. Arrows, bright F-actin/NMIIB spot at the rear of the translocating nucleus. Arrowheads, F-actin/NMIIB at cell surface constriction site. (B) Confocal single optical sections of mouse FL erythroblasts at various stages of enucleation immunostained for Tmod1 and Ter119, phalloidin for F-actin, and Hoechst for nuclei. Arrows, F-actin/Tmod1 cytoplasmic spot. Bars, 4 µm.