Inhibition of mTORC1 at various stages of embryonic development modulates the shape of craniofacial structures in both mice and zebrafish. A–C Pregnant C57BL/6 J dams were exposed to a single dose of either DMSO or rapamycin on E10.5 and stained with hematoxylin-eosin on E17.5. Representative images of the general appearance A or sagittal sections of their heads B, C are shown. D–F Embryos were treated as in A, but stained for SOX9 on E12.5 to reveal chondrogenic condensations D, E, the thickness of which in the three major nasal compartments was quantified in F. n = 4 or 6 animals in F. G–M The same treatment as in A was applied to Col2CreERT;R26RConfetti mice pulsed with tamoxifen on E12.5 and E13.5 and clonal appearance analyzed on E17.5 G–L and clonal size quantified M. 685 and 1133 clones obtained from 3 animals were quantified in M. N–SCol2a1aBAC:mcherry zebrafish larvae were exposed to DMSO or rapamycin at various periods in development. Ventral N, O and lateral P, Q views of the larvae exposed to DMSO N, P or rapamycin O, Q 14–22 h post-fertilization (hpf) and imaged at 120 hpf are shown. The facial length R and width P of 120-hpf-old Col2a1aBAC:mcherry zebrafish larvae exposed to rapamycin during the intervals of time indicated were quantified. n = 3–9 animals in R, S. Means ± SD are presented, with individual values also indicated. The two-sided unpaired t-test was employed to compare the values in F, M, and one-way ANOVA followed by Dunnett’s multiple comparisons test in R and S. Source data are provided as a Source Data file.
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