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Fig. 2. Male embryos lacking Hoxa13 exhibit decreased programmed cell death (PCD)
in the developing genital tubercle. (A) At E11.5, PCD is restricted to the
dUPE (arrowhead) and proximal UPE (pUPE) in heterozygous controls. (B) PCD is
reduced in the dUPE (arrowhead), but not in the pUPE of
Hoxa13GFP-homozygous mutants. (C) By E12.5, PCD shifts
from the dUPE to the mesenchyme (M) flanking the dUPE (arrow). (D) Homozygous
mutants also exhibit a shift in PCD to the flanking mesenchyme, although the
number of TUNEL-positive cells in the mutant mesenchyme is consistently
reduced when compared with heterozygous controls. Scale bars: 50 µm.