Does cre need to be homozygous?
Does cre need to be homozygous?
You should not need a homozygous Cre transgene for efficient recombination. Expression levels from a hemizygous transgene should be enough to see recombination. Randomly integrated transgenes can lead to surprising phenotypes when they are bred to homozygosity.
What does cre mean in mice?
It has been successfully applied in yeasts, plants, mammalian cell cultures and mice (Araki et al. 1987). It is based on the ability of the P1 bacteriophage cyclization recombination (Cre) recombinase gene (cre) to effect recombination between pairs of loxP sites.
How does cre mice work?
Cre recombinase proteins bind to the first and last 13 bp regions of a lox site forming a dimer. This dimer then binds to a dimer on another lox site to form a tetramer. The double stranded DNA is cut at both loxP sites by the Cre protein. The strands are then rejoined with DNA ligase in a quick and efficient process.
Can you cross two cre lines?
Assuming you are crossing two cre-driver lines, it is possible, but the number of mice required may become quite substantial depending on your intended outcome. If either of these lines expresses in the testes or ovaries, it will generate a germline mutation for the loxP flanked gene of interest. Vav1-Cre.
What are Cre mice used for?
The Cre/lox system is one of the most powerful and versatile tools developed for mouse genetics. It gives mouse researchers sophisticated control over the location and timing of gene expression. Cre/lox is usually used to make knockout alleles, but it can also be used to activate gene expression.
Is Cre-lox reversible?
All recombination events mediated by FLP or Cre are reversible. The loxP and FRT target sites have been engineered to avoid this re-inversion issue.
What is Cre-LOX used for?
What does Cre-LOX do?
What is Cre LOX used for?
Can you cross breed mice?
About 1 in 4 mice will be homozygous for the mutation at one, but not both, of the alleles. You can cross homozygous or heterozygous mice from your F1 generation to continue building your colony. You should genotype all of your F1 mice, as well as progeny from future generations.
Who invented Cre-lox?
Nat L. Sternberg
The origins of this tool date to more than 30 years ago when Nat L. Sternberg discovered the recombinase, Cre, and its specific locus of crossover, lox, while studying the maintenance of bacteriophage P1 as a stable plasmid.
How can I breed loxP and Cre mice?
2) Cross the heterozygous loxP, hemizygous cre mice back to the homozygous loxP, which will generate some homozygous loxP, hemizygous cre and some homozygous loxP, noncarrier mice (~25% of each), which are the genotypes needed for the end cross! See our previous blog post on Cre/lox Breeding for Dummies, which illustrates the same cross.
How to breed mice to create new models?
1) Breed your homozygous loxP mice (most will be homs) to your cre transgenic strain, which will generate mice that are heterozygous loxP , hemizygous cre .
Why are CRE Reporter mice used in research?
When researchers started creating Cre recombinase mouse strains to generate tissue specific knockout mice, they needed an easy way to confirm that Cre recombinase was active only in certain tissues. This need led to the development of Cre reporter strains.
What should the breeding scheme be for F1 mice?
In order to ensure that your genetic modification will be passed along to all of the offspring in the F1 generation, your breeding scheme should start with parental mice that are each homozygous for one of the two mutations that you want combined in your offspring.