Figure 1

a) Patterns of pigment motion and MT distribution in nascent fragments (left panel) [Movies 1(2.8 M) and 2(1.7 M)] and in fragments incubated for 120 min after dissection (right panel)[Movies 3(2.8 M) and 4(1.7 M)]; pigment aggregation in fragments dissected from non-treated cells (upper rows of the panels)[Movies 1(2.8 M) and 3(1.7 M)] and from cells pretreated with taxol (10-5 M) for 15 min (middle rows of the panels)[Movies 2(2.8 M) and 4(1.7 M)]; MT distribution in nascent fragments with dispersed (lower rows of the panels, left micrographs) and aggregated (lower rows of the panels, right micrographs) pigment. Numbers indicate time in sec after stimulation with adrenalin. Magnification bars, 20 mm.

b) Immunostaining for g-tubulin of intact cells and fragments; immunofluorescence micrographs showing distribution of MTs (left) and g-tubulin (right) for intact cell (upper row) and fragment incubated for 180 min after dissection (lower row); bar, 40 mm;

c) Microtubules in a fragment lacking pigment granules. Phase contrast images (upper row) and live fluorescence images of MTs (lower row) before (left) and after (right) adrenalin treatment. Reorganization of MTs did not occur in the absence of granules. Parental cell which served as a control responded normally to caffeine and adrenalin by pigment redispersion and aggregation. Bars, 20 mM