Cebpa enhancer deletion using Mb1-Cre does not reduce
marrow proB, early preB, or preB cells. (A) Diagram of breeding
strategy to obtain Cebpa Enh(f/f);Mb1-Cre mice (left). Examples
of WT versus floxed Cebpa enhancer and Mb1-Cre PCR analysis -
mouse 6 (underlined) has genotype Enh(f/f);Mb1-Cre (right). (B) RNA
from flow-sorted GMP, preproB, proB, and preB cells from WT mice was analyzed
for Mb1 mRNA expression relative to mS16 mRNA,
with expression in preB cells set to 1.0 (left, mean and SD from three
determinations). Genomic DNA from preproB, proB, early preB, and preB cells from
two Enh(f/f) and two Enh(f/f);Mb1-Cre mice were analyzed for retention of the
floxed Cebpa enhancer by PCR followed by agarose gel
electrophoresis and ethidium bromide staining (right). (C) Total
bone marrow mononuclear cells, Lin-Sca-1+c-kit+
(LSK) cells, GMP, CLP, preproB, proB, early preB, and preB cells were enumerated
in Enh(f/f) and Enh(f/f);Mb1-Cre littermates (mean and SD from three
determinations).