Rats are physiologically, morphologically, and genetically closer to humans than mice, which
makes rats ideal models for biomedical and clinical studies. Its larger body and organ size
facilitate multiple samplings, in vivo electrophysiology, as well as neurosurgical and
neuroimaging procedures. Rat models are widely used in toxicology, teratology, endocrinology,
oncology, neurology, experimental gerontology, cardiovascular research, dental research, and
experimental parasitology.
Cyagen has made significant advancements across most aspects of the rat model production
process, including ovulation promotion and improved fertilized egg injection techniques. Beyond
optimizing our production efficiency, such improvements have facilitated the creation of more
complex genetically modified rat models than previously feasible – bringing the generation costs
for rat models closer to that of mouse models.
Development of Conditional Models Using Cre/lox
The Cre/lox recombination enables the generation of tissue-specific or inducible knockouts
with a
high level of control over the spatial and temporal expression of genes.
CRISPR Capabilities for Rat Models:
-
● Standard Use -
Generate tissue-specific or inducible knockouts, such as in the
KO-first conditional allele strategy
-
● Transgene Switch -
a. Transgene Activation: A loxP-flanked “stop” sequence between the promoter and the
coding sequence blocks expression (until bred with a Cre strain)
b. Inducible Knockout: A loxP-flanked transgene sequence may be removed upon breeding
with a Cre strain
-
● Reporter Strains -
Reporter Strains – Visually confirm locations of Cre recombinase activity with
loxP-flanked fluorescent protein sequences
Despite the utility of the Cre/lox modeling strategy, the complexity of breeding protocol
alongside the increased cost of rat colony maintenance has created significant barriers for
researchers seeking to make novel conditional rat models.
Comprehensive cKO/cKI Rat Model Services
Cyagen can provide both the custom conditional knockout/knockin (cKO/cKI) rat models and the
associated Cre strains designed to fit your project needs.
| Service |
Background Strains Available |
Standard Deliverables |
| Conditional Knockout/Knockin Rat (Large fragment at any locus) |
Sprague-Dawley (SD), Wistar, F344, Long evans, Brown Norway - please inquire for
additional strains.
|
A minimum of one pair of homozygotes rats
+ one pair of Cre rats
|
| Conditional Knockin Rat (Large fragment at ROSA26) |
With our world-class facilities, we can perform any downstream breeding services to deliver
the perfect cohort for your research project.
Contact us for a free technical consultation and quote.
cKO/cKI Rat Models: Establishing a Cre Model Platform
One of the major constraints faced by researchers in developing conditional knockout (cKO)
or conditional knockin (cKI) rat models is the lack of Cre lines specific to the target of
interest. Given the higher facility fees associated with rats, the creation of all strains
necessary to achieve a Cre-lox rat strain can quickly become cost- or space-prohibitive. To
address this issue, Cyagen is building a repository of Cre models, including rat lines,
available to researchers worldwide.
Initial Rat Cre Lines Available*:
-
●
Crh-Cre
-
●
Agrp-Cre
-
●
Trpv1-Cre
-
●
Math5-Cre
-
●
Myh11-Cre
-
●
Cdh5-Cre
-
●
Pkhd1-Cre
-
●
Cx3cr1-Cre
*Above rat Cre lines are on the Sprague-Dawley (SD) strain background
Still looking for your Cre line? Cyagen can provide pricing accommodations to
researchers
interested in Cre lines not currently available in our listings. Contact us to inquire about
your conditional model needs and see how we can help develop a custom Cre strain to support
your field of study.
