Fig. 2. DiaCA triggers precocious amnioserosal apical
constriction. Drosophila embryos: anterior leftwards, genotypes
and antigens indicated. (A) Dia and DiaCA. (B-H,J,K,M-Q)
Dorsal closure. (B) DiaCA expression in entire amnioserosa
(c381-GAL4) (inset, DE-cad). (C-D'') DiaCA expression
in individual cells. Constricted cells expressing DiaCA
(arrowheads) and stretched wild-type cells (arrows).
(E,E') Wild-type amnioserosal cells have irregular shapes.
(F-G'') DiaCA expression in entire amnioserosa (F)
versus wild type (G). (H,H',J,J')
DiaCA expression in large group of amnioserosal cells showing Arm
(H) and Myosin (J) accumulation. (I) Apically constricting amnioserosal
cells (surface view left, cross-section right). (K) Myosin in wild-type
drop-out cell (arrow). (L) Immunoblot: 12-16 hour
DiaCAxe22c-GAL4 and wild-type embryos probed for MHC and
-catenin. Peanut is used as a loading control. (M-Q) Movie
frames showing Sqh::GFP under its own promoter. (M1-M3) Wild type. (N1-O5,Q,R)
DiaCA expression in amnioserosa (AS; c381-GAL4). (N1-N3) Drop-out
cells (arrowheads). (P,Q) Higher magnification views. (R) Cuticle:
DiaCA expression in amnioserosa. Scale bars: 20 µm.