Figure 6.

PDGFRα‐directed Cre recombinase expression in fetal tissues. PDGFRα‐CreER ^Tg;mTmG^fl/fl fetuses were collected at E18.5 after five (A), four (B), three (C), or two (D) consecutive days of tamoxifen gavaging. Fetuses express mEGFP signal in craniofacial bones (A1,B1,C1,D1) and vertebrae (A2,B2,C2,D2). E: Absence of GFP expression in fetal tissue whether tamoxifen is not administrated, either in craniofacial bones (E1) or vertebrae (E2). The dTomato signal was removed intentionally to give a better visualization of the leaking mEGFP signal in fetal tissues (A,B,C,D) or the absence of mEGFP signal in the negative control (E). Scale bar, left panel = 2 mm. Craniofacial bones, vertebrae images: 4X magnification of insets in the left panel. CreER, tamoxifen‐dependent Cre recombinase; E, embryonic day; mEGFP, membrane‐localized enhanced green fluorescent protein; PDGFRα, platelet‐derived growth factor receptor alpha