Characterization of transgene expression and Cre recombinase activity in a panel of Thy‐1 promoter‐Cre transgenic mice

The regulatory elements of the murine Thy1.2 gene were used to drive Cre recombinase expression in the nervous system (NS) of transgenic mice. Eleven Thy1-Cre lines exhibited transgene expression in several regions of the central and peripheral nervous systems, including the cerebral cortex, cerebellum, spinal cord, retina, and dorsal root ganglion. Thy1-Cre expression also resulted in region-specific activation of Cre reporter transgenes. Although Thy-1 expression is normally initiated in postmitotic neurons in the perinatal period, we show that the Thy-1.2 expression cassette drives Cre expression in immature proliferative zones in the NS as early as embryonic day 11 and in non-neural tissue. The Thy1.2 transgene cassette, therefore, does not impart transgene expression that is restricted to the NS or to postmitotic neurons within the NS. This panel of Thy1-Cre transgenic mice, however, will be useful reagents for the ablation of genes whose transcripts are spatially or temporally restricted in the developing NS.