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Fig. 4. Semiquantitative RT-PCR demonstrates late zygotic transcription of
Hro-hh. (A) Digital images of ethidium bromide-stained agarose gels.
Fragments of Hro-hh and 18S rRNA were amplified in separate reactions
carried out in parallel. (B) Amount of Hro-hh mRNA during
development, relative to stage 10 (100%). At each stage, the intensity of the
Hro-nos band was normalized against the 18S rRNA fragment (see
Materials and Methods for details). Each reaction sample contained template
cDNA equivalent to 4 embryos at the stage indicated [stage 4b
10 hours
AZD, stage 6a
19 hours AZD, stage 7
40 hours AZD, early/mid stage 8
(E/M8)
65 hours AZD, late stage 8 (L8)
88 hours AZD, early stage 9
(E9)
112 hours AZD, late stage 9 (L9)
140 hours AZD, stage 10
150 hours AZD, late stage 10/stage 11(L10/11) 170
185 AZD, late stage
11(L11)
195 AZD]. Squares indicate the data obtained from the gels shown
in (A); circles and triangles represent data obtained starting with
independent sets of embryos; black circles show the data from independent
PCR.