This antibody recognizes the recombinase protein, Cre. Cre is a 343 amino acid protein. CRE is a 343 amino acid protein. The Cre enzyme, belongs to a member of a large family of recombinases, recognizes loxP which is a sequence motif of 34 bp from the PI bateriophage. Cre and lox comprise the Cre/lox system which was first developed in the late 1980 to artificially manipulate gene expression. As an example, mice with the Cre protein expressing in a specific cell type are bred with mice that contain a target gene surrounded by loxP sites. When the mice are bred, the cells carrying Cre will cause those cells to lose the target gene. If the Cre gene is, for example, bound to a promoter that only allows Cre production in neuronal cells, the target gene will be deleted only in those cells. This has led to its application in many experiments, for example in selectively labeling neuronal cells in the brain thereby differentiating them from other types of surrounding cells.