Figure 1. Mechanism of Cre-loxP system. (A) An overview of Cre-loxP system. 38 kDa Cre recombinase recognizes the loxP sites of specific 34 bp DNA sequences. (B) General breeding strategy for conditional mutation using loxP and Cre driving mouse line. In principle, one mouse must have a tissue-specific driven cre gene and another mouse have loxP flanked (floxed) alleles of interest gene Y. Expression of Cre recombinase excises floxed loci and inactivates the gene Y.
