Detailed Cre-mediated β-galactosidase expression in tissue sections of transgenic embryos.

<p>17.5-day-old embryos with different genotypes (CreERT2+/−LacZ+/+ and CreERT2−/−LacZ+/+; strain #4) were collected after 3 days of tamoxifen induction and processed for histochemistry to detect β-galactosidase activity. Sections were either co-stained with Nuclear Fast Red (NFR) (<b>A</b>) or Tartrate-resistent acid phosphatase (TRAcP) (<b>B</b>). <b>a.1</b> and <b>a.3</b>: legs of CtsKCreERT2+/−LacZ+/+ embryos; <b>a.2</b> and <b>a.4:</b> legs of CtsKCreERT2−/−LacZ+/+ embryos; <b>a.5</b> and <b>a.7:</b> arms of CtsKCreERT2+/−LacZ+/− embryos; <b>a.6</b> and <b>a.8:</b> arms of CtsKCreERT2−/−LacZ+/+ embryos; <b>a.9</b> and <b>a.11:</b> vetebraes of CtsKCreERT2+/−LacZ+/− embryos; <b>a.10</b> and <b>a.12:</b> vetebraes of CtsKCreERT2−/−LacZ+/+ embryos. <b>b.1, b.3</b> and <b>b.5:</b> arms of CtsKCreERT2+/−LacZ+/+ embryos; <b>b.2, b.4</b> and <b>b.6:</b> arms of CtsKCreERT2−/−LacZ+/+ embryos.