Comparative analysis of two independent Myh6-Cre transgenic mouse lines.

We have previously shown that the promoter drives Cre expression in a subset of male germ line cells in three independent mouse lines, including two transgenic lines and one knock-in allele. In this study, we further compared the tissue-specificity of the two transgenic mouse lines, through examining the expression of tdTomato (tdTom) red fluorescence protein in multiple internal organs, including the heart, brain, liver, lung, pancreas and brown adipose tissue. Our results show that mainly activates tdTom reporter in the heart, whereas activates tdTom expression significantly in the heart, and in the cells of liver, pancreas and brain. In the heart, similar to , activates tdTom in most cardiomyocytes. In the other organs, not only mosaically activates tdTom in some parenchymal cells, such as hepatocytes in the liver and neurons in the brain, but also turns on tdTom in some interstitial cells of unknown identity.