Figure 3. Cellularization microfilament defects in src64 mutant embryos.

Embryos are stained with antibody to myosin II heavy chain. (A) Cross-sections showing the early cellularization front. Furrow canal depths are less uniform, producing a wavy and irregular cellularization front in src64^Δ17, src64^H402L, src64^D404N and src64^KO mutant embryos. Scale bar, 50 µm. (B) Grazing section projections of early cellularization stage embryos showing the microfilament network. Microfilament rings of src64^Δ17, src64^H402L, src64^D404N and src64^KO mutant embryos are irregular. Scale bar, 10 µm. (C) Grazing section projections of late cellularization stage embryos showing microfilament rings. Microfilament rings of src64^Δ17, src64^H402L, src64^D404N and src64^KO mutant embryos are irregular and less constricted than the microfilament rings of wild-type embryos and src64^R403C mutant embryos. Scale bar, 10 µm. (D) Microfilament ring circularity during early cellularization. A, does not differ from +; AB, differs from + and src64^Δ17; B, does not differ from src64^Δ17 allele but differs from + (P<0.01); C, does not differ from src64^KO but differs from + (P<0.001) and src64^Δ17 (P<0.001). Error bars are SEM. (E) Microfilament ring circularity during late cellularization. A, does not differ from +; B, does not differ from src64^Δ17 but differs from + (P<0.05); C, does not differ from src64^KO but differs from + (P<0.001) and src64^Δ17 (P<0.001). Error bars are SEM.