Fig. 6. Inactivating M/Z Ena disrupts morphogenesis. F-actin. (A-D) M/Zena²³. Late germband retraction. Arrowheads, deep segmental grooves; arrow, uneven leading edge. (E-N) Onset of dorsal closure. (E-H) Deep segmental grooves (E-H, arrowheads). Arrows, failure of epidermal-zipping relative to wild type (E) or paternally rescued mutant (G). (I-L) Close-ups. Arrows, actin cable; arrowhead, cells elongating; brackets, occasional cells with disrupted actin cable and splayed-open leading edges. (M,N) More severely affected mat-FP4mito embryo. Note deep segmental grooves (M, arrowheads) and defects in cell-shape changes (N, arrowheads). Actin cable is largely normal (N, arrow). (O-U) Mid-late dorsal closure. Wild-type (Q), paternally rescued mutants (O,R), mat-FP4mito (T,U, close-up) and M/Zena²³ mutant (P,S). Note head involution failure (S,T, brackets), persistent deep grooves (T,U, arrowheads) and slow epidermal-zipping (Q-S, arrows). (V,W) End of dorsal closure. Arrows, dorsal midline. (X) Terminal-stage mat-FP4mito. Bracket, severe head defects. Scale bars: 20 µm.