Fig. 10 Redundant signals contribute to furrow formation in the early blastomeres.
Wild-type (A–D) and cei; fue double mutant (E–H) embryos were fixed at 49 min p.f. and labeled with anti–α-tubulin antibodies (A,E; red in D,H), anti–γ-tubulin antibodies (B,F; green in D,H) and DAPI (C,G; blue in D,H). (A–D) At this stage, wild-type embryos exhibit an FMA along the span of the first cleavage plane (1st). (E–H) cei; fue double mutant embryos lack an FMA in either medial or distal regions of the 1st cleavage plane (compare to Figure 3D,H). Double mutants show the expected delay in furrow induction, characteristic of the cei mutation, in the less mature furrow corresponding to the 2nd cleavage plane (arrowhead in (E); compare to Figure 3B and 3F). Double mutants also exhibit the pronuclear fusion defect characteristic of the fue mutation [31]. Similar results can be observed in embryos until 65 min p.f. (not shown).