Conditional Knockout and Lineage Tracing of Cebpa in Hematopoietic Stem Cells

Cebpa^loxP/loxP mice (kind gift of Daniel G. Tenen) were previously described (Zhang et al., 2004 (link)). HSC-SCL-Cre-ER^T transgenic mice were generously provided by Joachim Göthert (Göthert et al., 2005 (link)). R26R-EYFP transgenic reporter mice were generously provided by Dennis Roop (Srinivas et al., 2001 (link)). All mice were backcrossed for at least five generations on a C57BL/6 background and bred to be heterozygous for R26R-EYFP and heterozygous for HSC-SCL-Cre-ER^T, while each litter contained a mixture of Cebpa genotypes, such that Cebpa^+/+ and Cebpa^Δ/Δ littermates were used in experiments. To induce recombination, mice were treated i.p. with 2.5 mg of tamoxifen (prepared at 10 mg/ml in corn oil) daily for 3 d and were used for experiments 7 d after the final dose of tamoxifen. Genotyping of mice and detection of recombined product were as previously described (Zhang et al., 2004 (link)). C57BL/6 (Ly5.2) and congenic (Ly5.1) mice were ordered from Charles River Laboratories. All procedures were performed in accordance with the University of Colorado Anschutz Medical Campus Institutional Animal Care and Use Committee–approved animal protocols.