Tg(Dmp1-cre)1Btm

This transgene contains the cre recombinase coding sequence downstream of a 12-kb DNA fragment from the mouse dentin matrix protein 1 (Dmp1) gene containing ~8 kb of 5' flanking sequence, the first exon, the first intron and 17 bp of exon 2. Cre recombinase transcripts are detected in bone of 1-month-old transgenic mice, but not in brain, heart, kidney or skeletal muscle. However, deletion of a loxP-flanked sequence is observed at low levels in brain. RT-PCR analysis of FACS-sorted calvarial cells from neonatal transgenic mice revealed the presence of cre recombinase transcripts only in cells containing high levels of mRNA encoding the osteocyte marker sclerostin (SOST) and low levels of the osteoblast marker keratocan. (J:210294)