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Fig. 12. Effect of D2O and nocodazole on microtubule density near the
embryo surface. Wholemount confocal microscopy of embryos stained for
ß-tubulin. (A) Furrow region of untreated cleaving embryo. (B) The
same embryo, non-furrowing surface of animal hemisphere. Inset is vertical
resection at the site indicated by the white horizontal line. (C) Animal
surface of D2O-treated embryo, showing through-surface view of a
microtubule monaster. The inset is a vertical resection that indicates
monastral microtubules are within 1 or 2 µm of the surface. (D) Nocodazole
treatment completely eliminates surface microtubules. (E) Nocodazole treatment
eliminates surface microtubules in a D2O-incubated embryo. Bar, 10
µm.