(1)Mice expressing exogenous Cre recombinase in the cochlea but not in the placenta. The Cre gene is either knocked in at the site of foxg1 [7] (foxg1Cre/+ mice) or expressed from a bacterial artificial chromosome (BAC) that
Lumacaftor contains the Cre coding sequence at the locus of the pax2 (pax2-cre mice) [8]. Heterozygous foxg1cre/+ mice were obtained from the Jackson Laboratories (Bar Harbor, ME). Pax2-cre mice were obtained from mutant mouse regional resource centers (http://www.mmrrc.org/). Both foxg1Cre/+ and pax2-cre mice showed normal hearing (data not shown);(2)Mice in which the exon2 of the Gjb2 gene is flanked by the loxP sequence (Cx26loxP/loxP mice). The exon2 of the Gjb2 contains the entire coding region for the Cx26. Activation of Cre recombinase is expected to totally remove the
expression of Cx26. The Cx26loxP/loxP breeding pairs were obtained from the European mouse mutant archive (http://www.emmanet.org/) with the written permission of Dr. Claus Willecke. Previous studies show that the hearing of Cx26loxP/loxP mice is normal [4].Crossbreeding of the above mice generated foxg1cre/+;Cx26loxP/loxP and pax2-Cre;Cx26loxP/loxP mice. They will be called the foxg1-Cre and pax2-Cre cCx26 null mice, respectively. Spatially-specific Cre expression pattern in these mouse models was examined by using the R26R LacZ reporter mice [9] (provided by Dr. Ping Chen, Emory University). Details of the methods for the use of R26R LacZ reporter mice can be found in our previous publications [10].
