Comparative analysis of potential broad-spectrum neuronal Cre drivers.

Cre/Lox technology is a powerful tool in the mouse genetics tool-box as it enables tissue-specific and inducible mutagenesis of specific gene loci. Correct interpretation of phenotypes depends upon knowledge of the Cre expression pattern in the chosen mouse driver line to ensure that appropriate cell types are targeted. For studies of the brain and neurological disease a pan-neuronal promoter that reliably drives efficient neuron-specific transgene expression would be valuable. Here we compare a widely used "pan-neuronal" mouse Cre driver line, , with a little-known alternative, . Our results show that the line broadly expresses in the brain but is indetectable in more than half of all neurons and weakly active in testes. In contrast the line expressed Cre in a high proportion of neurons (~85%) and was indetectable in all non-brain tissues that were analysed, including testes. Our findings suggest that for many purposes is superior to as a potential pan-neuronal cre driver.