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Cre Recombinase

The Essential Use of Cre Recombinase in the Creation of Floxed Mice

The creation of floxed mice can help geneticists and experts in genetic diseases to study highly specific occurrences of the diseases and how they progress over time. “Floxing” is the action of flanking a gene using two separate loxP sites, and its name was actually derived from the term “flanking by loxP.” The appropriate placement of Lox sequences can facilitate the accurate activation or repression of genes, as well as their exchange for other genes. In essence, the method allows scientists to manipulate specific genes in the mouse genome in order to study results that may help determine whether or not a treatment for a type of genetic disease will be effective in both mice and humans.

How Does Cre Recombinase Aid in the Production of Floxed Genes?

Before delving into the details of why the Cre recombinase and the Cre/lox recombination method is so effective for facilitating the floxing of genes and producing targeted conditional alleles, it’s important to first understand how the method itself works. Cre recombinase is a tyrosine enzyme that can be used efficiently in the Cre recombination system in order to carry out site-specific recombination events and ultimately catalyze the recombination event between two specifically chosen DNA recognition sites, which are also known as LoxP sites. This, as well as the product of its catalyzing effect, will be determined by the relative orientation and the particular location of the loxP sites.

So, where does floxing come into all this? As two separate loxP sites undergo fusion as a result of the use of Cre recombinase, the DNA sequence that is located between those two sites will become “floxed.” In this case, the location of the Cre recombination sequence is precisely determined, and the product of the floxing will depend entirely on the orientation of the two loxP sites. Should the sites be oriented in the same direction, the result will be a circular DNA loop. If, on the other hand, the orientation of the two sites oppose each other, the DNA found between the two loxP sites will be inverted.

When it comes to the creation of flox mice, the use of the Cre/lox recombination system is extremely valuable. It is in fact considered to be one of the most powerful and important tools in the mouse geneticist’s arsenal. The reason for that is the Cre/lox recombination method’s ability to produce tissue-specific knockouts, as well as other highly specific and accurate spacial and temporal alterations of gene expression.

In terms of using mice to study various genetic diseases or the use of untested prototype drugs and treatments, the specific alteration of genetic expression in various tissues can be essential, if not life-saving. It saves a significant amount of time and energy, as well as producing remarkably accurate results that medical experts and geneticists would not be able to obtain otherwise. When it comes to the future of genetic research, the use of floxed mice and gene alteration through the Cre/lox recombination method is expected to play an even greater role in future research.