A Unique Role for Nonmuscle Myosin Heavy Chain IIA in Regulation of Epithelial Apical Junctions (original) (raw)
Figure 8
siRNA knock-down of NMMIIA causes disorganization of F-actin cytoskeleton.
Calcium-depleted control and NMMIIA-deficient SK-CO15 cell monolayers were transferred into the HCM for 0.5 h (A) and 5 h (B) to trigger junctional reassembly. Organization of their actin filaments was visualized using fluorescently labeled phalloidin. At the early time of calcium repletion, prominent radial F-actin cables can be seen in lamellipodia of spreading/contacting control cells (A, arrows). At a later time, control cells show circumferential apical F-actin bundles (B, arrowheads). Neither structure is formed in NMMIIA-deficient cells which show diffuse (A) or abnormally aggregated (B, stars) F-actin. Bar, 10 µm.