Comparative study of the impact of the actin cytoskeleton on cell shape and membrane surface in mammalian cells in response to actin toxins

We performed a correlative epifluorescence and scanning electron microscopy study of the morphological alterations, both in the actin cytoskeleton organization and in the cellular shape and surface morphology of HeLa, NRK and Vero cells, caused by a variety of actin toxins. To this end, we used actin toxins that depolymerize (cytochalasin D, latrunculin B, and Clostridium botulinum C2 toxin) or stabilize (jasplakinolide) filamentous actin. By immunofluorescence we observed that the resulting actin cytoskeleton alterations were cell typeand toxin-dependent. Analysis of the cell shape and membrane surface by scanning electron microscopy also showed that the actin disruption produced variable changes depending on the cell type and the actin toxin used. Therefore, our results indicate that actin directly participates both in the maintenance of cell shape and in membrane surface morphology, revealing significant differences depending on the actin toxin and cell type involved.