Tg(Cspg4-cre/Esr1*)BAkik

The 208 kb C57BL/6J mouse bacterial artificial chromosome (BAC) RP23-309G21, containing the entire NG2 (Cspg4) gene (and 60 kbp of 5' and 114 kbp of 3' flanking sequences), was modified by inserting a CreERTM fusion gene (cre recombinase fused to a G525R mutant form of the mouse estrogen receptor ligand-binding domain) followed by a rabbit beta-globin polyA signal, into the first exon of the NG2 gene. The NG2 translation initiation ATG was changed to AAG to prevent the translation from the BAC NG2 gene and to allow translation from the first ATG in the CreERTM sequence. The ~219 kb BAC sequence was linearized and microinjected into the pronucleus of fertilized oocytes from C57BL/6 or (C57BL/6 x SJL)F1 mice. Mice derived from line B (NG2creERB) had no background cre activity in the absence of tamoxifen, with cre activity specifically in NG2-expressing cells after tamoxifen injection. Transgene insertion occurred on Chr 14, causing a 628 bp deletion. (J:162529, J:167902)