Looking for knockout mice or rats not included in our standard model portfolio? Your Horizon in vivo model development specialist will work with you to design a custom model to your exact specifications, using our CRISPR-Cas9 (licensed by Caribou Biosciences and the Broad Institute) or Zinc Finger Nuclease technologies, in as few as 5 months.
Design your custom model with our SAGEspeed Custom Model Builder.
With SAGEspeed, you're no longer limited to just a few strains of mice. We're able to modify almost any strain in not just mice, but rats and rabbits as well. Let your research decide the model, not the technology.
|C57BV6||Sprague-Dawley||New Zealand and White|
|FVB||Long -Evans Hooded|
|CBA CA||Fischer 344|
Our scientific team can work with you to design custom knockout mice, rats or rabbits to your exact specifications using CRISPR-Cas9 or ZFNs. Beyond constitutive knockouts, we offer more sophisticated project types — humanization, conditional knockouts, point mutations and reporter tagging.
|Gene Knockout||Gene Mutation/Replacement||Targeted Transgenic|
As CRISPR-Cas9 and ZFN technologies directly enable targeted mutagenesis at the single cell stage, embryonic stem cells are not required – making model generation much faster and without background strain limitations. These technologies are utilized to generate sequence-specific double-strand breaks that are repaired by error-prone nonhomologous end joining (NHEJ) or high-fidelity homologous recombination (HR).
NHEJ is utilized for generating targeted gene knockout. A nuclease (plus guide for CRISPR) targeting the desired gene is microinjected into the pronucleus of fertilized one-cell embryos that are guaranteed to be germline transmissible. Knockouts are generated by introducing variable genomic insertions or deletions that result in a frameshift within the open reading frame, which can result in the introduction of premature stop codons. When the premature stop codon occurs before the last exon, the transcript is degraded via the nonsense-mediated decay pathway and little or no protein is expressed. Efficiency for generating knockout founders is 10-20% in resulting litters.
The HR pathway is utilized for generating the targeted integration of the desired DNA sequence. Point mutations, humanized sequences or reporter tags are synthesized and cloned into a donor vector backbone. Microinjection of the nuclease (plus guide for CRISPR) and the donor vector into the pronucleus of fertilized, one-cell embryos, efficiently generates HR-mediated mutants that are guaranteed germline transmissible. While NHEJ-mediated knockouts occur at a high founder rate, generating donor-mediated mutants occurs less frequently and often requires an increased number of microinjected embryos and resulting pups to screen.
Resulting founders are screened for mutations by developing PCR primers that flank the targeting site to screen appropriate integration and rule out random insertion of the donor (if appropriate) into the genome. Founders are confirmed by sequencing.
Get a head start with our SAGE Transgenic Services. These services offer a quick and convenient way to protect and characterize your SAGEspeed Custom Model. A wide variety of services are available to support the breeding, sampling or storage of your models or to perform in vivo assays.