Figure 7.
HHIP1–HS interaction promotes long-range inhibition of HH-dependent patterning and proliferation. (A–T) Hamburger–Hamilton stage 11–13 chicken embryos electroporated with mHhip1-pCIG (A–E and K–O) and mHhip1ΔHS1/2-pCIG (F–J and P–T) were collected at 24 hpe (A–J) and 48 hpe (K–T), sectioned at the wing axial level, and immunostained with antibodies raised against NKX6.1 (B, C, G, H, L, M, Q, and R) and PAX7 (D, E, I, J, N, O, S, and T). (C, E, H, J, M, O, R, and T) Electroporated cells express nuclear EGFP. (A, F, K, and P) DAPI stains nuclei (gray). White lines indicate non–cell-autonomous repression of NKX6.1 expression (B, C, G, and H) and ectopic expansion of PAX7 (D, E, I, and J). (D, E, I, and J) White arrowheads demarcate the ventral most electroporated cell. Brackets in K–M and P–R denote the size of the NKX6.1+ domain. (U and V) Quantitation of PH3+ cells in embryos electroporated with the indicated constructs and collected at 24 hpe (U) and 48 hpe (V). Data are presented as mean ± SEM. P-values determined by Student’s two-tailed t test. Bar, 50 µm.