JCS02353 Supplementary Material

Files in this Data Supplement:

• Supplemental Figure 1 -

  Fig. S1. 16.5-hour-old zygote injected with a low amount of RT at 5 hours AF. Almost no fluorescence is detected in the zygote but aggregates of RT remain in the seawater close to the injection site (1). Bundles are detected at the rhizoid pole (arrow) 2 hours later (2). (Projection of all sections.)

• Supplemental Figure 2 -

  Fig. S2. Unprocessed images of RT-injected zygotes (corresponding to Figs 2A,D and 2I,L). Although a much lower tubulin amount has been injected in the lower zygote bundling is observed as it is in the upper zygote.

• Supplemental Figure 3 -

  Fig. S3. Bundling and foci at mitosis entry in the rhizoid of a zygote injected with a low amount of tubulin. Tubulin was injected at 5 hours AF. At 18 hours AF a crescent of bundled MTs is apparent at the rhizoid tip. One hour later, the rhizoid has grown and bundled MTs extend toward the rhizoid collar (2). The amount of tubulin injected is such that neither the perinuclear network nor the nucleus could be detected in the unprocessed image (3) and the nucleus could be only be faintly detected following significant contrast enhancement (4). The rhizoid has elongated by 23 hours AF and does not enlarge or swell, and bundled MTs are still seen (5). The transmitted image at 24 hours AF and the projection of all sections have been superimposed (6) to show the morphology of the rhizoid which is normal. Only foci (white) remain at the rhizoid collar.

• Supplemental Figure 4 -

  Fig. S4. Unprocessed (top) and enhanced (bottom) images (projections of all sections) of a zygote injected with RT at 4 hours AF. Bright spots in the seawater correspond to tubulin that escaped from the pipette before entering the zygote. At 10 hours AF the cortical array was very faintly labelled (1) and could not be detected without contrast enhancement. At 20 hours AF the zygote had germinated and MTs could be seen to radiate from a focus (2). Most of the MTs are bundled. At 22 hours AF the focus has disappeared and MTs are more bundled in the elongating rhizoid (3) (projection of all sections).

• Supplemental Figure 5 -

  Fig. S5. Unprocessed (top) and contrast-enhanced images (bottom) of a zygote injected with RT at 4 hours AF. At 10 hours AF the cortical array was very faintly labelled and could be detected only after significant contrast enhancement (1). The nuclear area was similarly only visible after contrast enhancement (2, lower image). At 20 hours AF metaphase was detected and foci remained at the rhizoid collar.

• Supplemental Figure 6 -

  Fig. S6. Unprocessed (top) and contrast-enhanced (bottom) images of a zygote injected with a low amount of RT. Unpolarised zygote at 55 hours AF (3-4 hours after injection) (1); mitosis entry at 20.5 hours AF. Note the foci at the collar and the rhizoid tip (2). The foci disappear during mitotic progression at 22 hours AF (3).

• Supplemental Figure 7 -

  Fig. S7. Effect of latrunculin-B on MT arrays. Latrunculin B (10 nM) was added at 10 hours AF (1) (projection of all sections). (2) The same zygote 2 hours after treatment showing disruption of the cortical array. Fluorescence at the top right of the zygote corresponds to tubulin in the medium that adhered to the zygote.