Fig. 3. Disassembly and reassembly of MTs upon cell membrane disruption is dependent on extracellular Ca²⁺ concentration. (A) A PtK2 cell expressing -tubulin-EGFP was wounded in 0.4 mM-Ca²⁺ Ringer's solution. The asterisk indicates the site of cell membrane disruption. The cell membrane disruption induced MT disassembly around the wound site, but the propagation of the MT disassembled area was slower than in 1.8 mM Ca²⁺ Ringer's solution. Arrows indicate disassembled MTs. (B,C) MT ends did not approach the wound site in 0.4 mM Ca²⁺ Ringer's solution. Colored dots indicate selected MT ends.