A C. elegans embryo expressing AJM-1::GFP in which the
founder cell Cpaa was ablated to remove the left-hand
dorsal epidermal cells [Ryan King]. Such ablations allow
examination of cell autonomy during epithelial cell
rearrangement.
Dorsal epidermal
cells comprise two rows of epithelial cells that lie along
the dorsal midline and extend along much of the
anterior-posterior axis. These cells intercalate to form a
single row of cells. Since there are only 20 cells that
intercalate, it is perhaps the simplest known system for
studying directed cell rearrangement during embryonic
development.
We are studying how Wnt signaling, mediated through the
Dishevelleds mig-5 and dsh-2, the b-catenins wrm-1 and
hmp-2, and the divergent b-catenin sys-1, regulate
patterning and morphogenesis during dorsal
intercalation.