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Fig. 6. Absence of Six1 does not lead to an increase in apoptosis in
Six1-expressing cells. TUNEL assays at the forelimb bud level of E11
Six1/ and Six1+/
embryos (A,B,D,E). Six1-expressing cells are detected by an antibody against
ß-galactosidase (B,C,E,F). (A-C) Apoptosis in
Six1/ embryos (A) is not increased in the
dorsal and ventral aspects of the limb bud where Six1-positive migrating
myogenic cells are detected (C), as revealed by double staining (B). (D-F) In
Six1+/ embryos, similarly no massive apoptosis is
detected in ventral and dorsal regions of the limbs (D) where Six1-positive
cells accumulate (F), as revealed by double staining (E).