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Fig. 3. Zebrafish tbx5 is necessary for fgf10 and fgf8
expression in the pectoral fin budding region. All panels show the dorsal view
of zebrafish embryos with anterior to the top. (A-D) Comparison of
fgf10 and fgf8 expression patterns in embryos injected with
10 ng of control (A,C) or tbx5 (B and D) morpholino. (A and B)
fgf10 expression in the pectoral fin bud region of 26 hpf (A,
arrowheads) was not detected in the tbx5-morpholino injected embryo
(B, asterisks). Note that expression remains unchanged in other regions of the
embryo. (C and D) In 36 hpf tbx5-morpholino-injected embryos,
fgf8 expression could not be detected in the region where the
pectoral fin buds develop (D, asterisks), as compared to the control embryos
(C, arrowheads point to the expression in the apical fold). fgf8
expression in the midbrain-hindbrain boundary remains unaltered in the
injected embryos, as noted by the arrows. (E) fgf10 was not detected
in the pectoral fin bud region of 24 hpf hst mutants (asterisks), but remained
unaltered in other regions.