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Fig. 5. Specification of facial branchio-motoneurons is not affected by
Nkx6.1 inactivation. In situ hybridization with Isl1 (A,B)
and Isl2 (D,E) on flat-mounted hindbrains of E10.5 wild-type (A,D)
and Nkx6.1 mutant (B,E) embryos. (B) Nkx6.1 mutant embryos
generate Isl1-positive cells throughout the hindbrain. (C)
Quantification of Isl1-positive facial branchio-motoneurons at r4 levels of
wild-type and Nkx6.1 mutant embryos at E10.5 and E12.5. Using
immunohistochemistry with an anti-Isl1 antibody on coronal hindbrain sections,
Isl1-positive nuclei on 12 representative sections for each genotype and age
were counted. Values are shown as % of wild type, mean±s.d. (D,E)
Isl2 marks somatic motoneurons and the otic ganglion.
Isl2-positive motoneurons are not detected in hindbrains of
Nkx6.1 mutants (E). (F-S) In situ hybridization with Olig2
(F,G), Irx3 (H,I), Dbx2 (J,K), Dbx1 (L,M) and
Ebf1 (R,S) and co-immunofluorescence detection of En1 (N,O) or Evx1
(P,Q) together with Phox2b (N-Q) on sections through r4 of wild-type
(F,H,J,L,N,P,R) and Nkx6.1 mutant embryos (G,I,K,M,O,Q,S) at E10.5.
These markers are similarly expressed in wild-type and in Nkx6.1
mutant embryos.