Fig. 7
From: Limb patterning genes and heterochronic development of the emu wing bud
Delayed expression of Sonic Hedgehog (Shh) in emu forelimb buds. Whole-mount in situ hybridization and RNA-seq. a Equivalent expression of Shh in both forelimb and hindlimb buds of chicken embryo (stages 21 and 23). b RNA-seq analysis at stage 20, showing lower level of Shh expression emu forelimb bud (stages 20–21) compared to hindlimb buds, but not in the chicken. c Delayed Shh expression in emu embryo forelimb buds relative to hindlimb buds (HH stages 20–25). Arrows show forelimb and hindlimb buds (outlined). d Co-localization of Fgf8 and Shh mRNA in stages 20 and 22 emu limb buds, showing robust Fgf8 expression but lower and delayed expression of Shh in forelimb versus hindlimb buds