A. Wholemount ISH of Wnt5a in the developing E13.5 GT showing ventral,
lateral, dorsal, transverse and longitudinal views, as well as Wnt5a
expression in the limb (dorsal view). di, distal; pr, proximal; d, dorsal;
v, ventral; a, anterior; p, posterior. B. Pseudo-colored expression pattern
overlays of known and candidate genes of a Wnt5a network.
Experimental WISH images of stage-matched genital tubercles at 13.5dpc were
pseudo-colored and overlaid with either Wnt5a (a–e,
a′–e′). Ventral (v; a–e) and dorsal (d;
a′–e′) views are shown and the edge of the GT is
outlined with a dotted line. Wnt5a network genes include
Wnt5a alone (a, a′),
Wnt5a/Dkk1/Lef1 (b, b′),
Wnt5a/Dkk1/Frzb (c, c′),
Wnt5a/Dkk1/Kcnab1 (d, d′) and
Wnt5a/Dkk1/Shox2 (e, e′). Arrows indicate the
border of the Wnt5a distal GT expression domain. All genes
showed some degree of overlap with the Wnt5a domain.
Dkk1 showed overlapping expression with
Lef1 (b, b′) and Frzb (c,
c′), in contrast to Kcnab1 (d, d′) and
Shox2 (e, e′), which did not overlap with the
distal Dkk1 domain. C. GT mesenchyme-enriched gene cluster
associated via hierarchical clustering decorated with GO terms and known
transcription factor binding sites and known human and mouse phenotype
associations. This cluster shows strong links to limb morphogenesis,
particularly of mesodermal elements including cartilage and bone.