Fig. 7
From: Co-option of the cardiac transcription factor Nkx2.5 during development of the emu wing
Impact of Nkx2.5 mis-expression on expression of essential limb-patterning genes. In situ hybridization of forelimb buds 2 days after infecting the right wing bud with Nkx2.5-expressing virus. a, c, e, g, i left (uninfected) and b, d, f, h, j right (infected) forelimb buds of the same embryo. a, b HoxD13, c, d Fgf8, e, f Fgf4, g, h Shh, i, j Tbx5 (n = 3 for HoxD13, Fgf4 and 8, n = 9 for Shh). Orientation of limb buds is as illustrated bottom right. k Nkx2.5 expression reduces proliferation in limb bud mesenchyme. Control limb bud mesenchyme possesses 74.1 ± 4.8 (mean ± SD, n = 3) proliferating cells per unit area, while Nkx2.5-expressing limb buds have 41.7 ± 7.3 proliferating cells per unit area (n = 5). l Cell death in response to Nkx2.5 mis-expression in chick limb buds (mean ± SD, n = 3 for control and Nkx2.5-expressing embryos). Statistical significance calculated using Student’s t-test. Scale bars = 0.5 mm
