Kras Conditional Knockout mouse — liver specific context
Kras, the mouse ortholog of human KRAS, encodes the Ras isoform on which most epithelial tumors depend, a GTPase governed by Sos1-mediated exchange and by Nf1 and Rasa1 GAP activity, coupling receptor input to Raf, PI3K, and Ral effectors; unlike Hras it is farnesylated without palmitoylation and carries a polybasic hypervariable region, and alternative fourth-exon splicing produces the 4A and 4B isoforms with different membrane behavior. Codon 12, 13, and 61 substitutions abolish GAP-stimulated hydrolysis, and allele identity matters pharmacologically, since Gly12Cys and Gly12Asp are addressed by chemically distinct inhibitors. Homozygous deletion is embryonic lethal, uniquely among Ras genes, so conditional nulls are required, while Lox-Stop-Lox oncogenic knockins expressed at endogenous levels remain the standard for tumor initiation and humanization enables clinical-compound pharmacokinetic and pharmacodynamic testing. Hras and Nras can substitute developmentally when knocked into the Kras locus, evidence that dosage and localization, not sequence identity, drive the essential requirement.
Tissue restricted knockout of Kras keeps wild type function everywhere else. Breeding is often more robust, and the setup mirrors patient biology where mutations arise in a subset of cells. For liver work, plan Cre specificity, reporter crosses, and baseline phenotyping before you scale.
Catalog options
Conditional knockout focuses the experiment on liver while the rest of the animal keeps a wild type allele. That pattern mirrors somatic mutation in patients and avoids systemic compensation that can erase subtle phenotypes. It is often preferred when a germline null is lethal, weak, or confounded by developmental rescue.
| Model | Type | Category | Availability | Catalog # | |
|---|---|---|---|---|---|
| Kras-Flox | Conditional Knockout | KO/CKO mice | sperm cryopreservation | CKO 2101910 | Inquire |
Designing a Kras Conditional Knockout allele
The most useful application of a Kras conditional is not loss-of-function phenotyping but dependency testing, because widespread deletion in adult animals is tolerated even though the same deletion in the embryo is lethal, and that timing difference is itself the result. Flanking the first coding exon removes both alternatively spliced products, so the allele cannot leave a partially functional isoform behind. Two experiments justify the build. Deleting the remaining wild-type allele in a mutant-driven tumor tests whether normal Kras restrains the oncogenic one, a genetic relationship that copy-number data alone cannot establish. Deleting the oncogenic allele after tumors are established tests maintenance rather than initiation. A whole-body tamoxifen-inducible driver suits the first question; tissue-restricted drivers such as Pdx1-Cre or Lyz2-Cre suit lineage work. Confirm recombination in sorted tumor cells and read out phospho-ERK and phospho-AKT alongside regression kinetics.
Pricing and quotes
The Kras Conditional Knockout lines listed above are catalog models. Send us the catalog number and our team confirms current availability, pricing, and whether the line ships cryopreserved or live.
If your study needs a Kras allele configuration that is not listed above, our scientific team designs and generates it. Model generation quotes return in about twenty four hours with milestones for genotyping, QC, and dispatch.
FAQ
What Kras Conditional Knockout mouse models are available?
When Kras Conditional Knockout lines are in catalog, we ship from inventory. If your configuration is not listed, we design the allele to order. Common paths include conditional knockout, constitutive knockout, humanized, knockin, and transgenic options, with documented germline transmission and United States QC.
Is Kras knockout embryonic lethal in mice?
It depends on background and allele design. Some Kras germline knockouts are viable. Others need conditional alleles or mixed backgrounds. We review publications and our own experience, then recommend floxed versus null before you commit.
Which Cre driver is best for liver specific focused experiments?
Driver choice depends on onset timing, recombination efficiency, and known leak. We map your organ and cell type to a short list of proven Cre lines, then talk through reporter crosses and controls. Your note points to liver specific, so we start driver selection there.
Do you ship live Kras animals?
When catalog lines are live, we ship with health certificates and QC documentation. If your exact combo is not listed, we quote a generation project with cryo or live dispatch depending on cohort timing and geography.
How do I request a quote for Kras?
Use the catalog inquire buttons or the request quote form. Include your allele goal, Cre plan if any, strain background, and cohort size. A PhD led team responds with pricing, milestones, and the fastest path to experimental animals.