Gene Editing Rat Resource Center (GERRC): Rat models for heart, lung and blood studies
Authors: Dwinell Melinda , Schilling Rebecca , Gryzbowski Michael , Temple Anne , Zappa Allison , Lazcares Lynn , Niebuhr Jessica , Kalloway Shawn , Foeckler Jamie , Takizawa Akiko , Geurts Aron 
Published: June 2021

Genome editing in the rat through the use of Zinc‐Finger Nucleases (ZFNs), TAL Effector Nucleases (TALENs) and Clustered Regularly Interspaced Short Palindromic Repeats‐Cas9 (CRISPR/Cas9) nuclease systems has produced gene‐modified strains which can be used to validate a gene underlying a quantitative trait locus, to test a nominated human gene or to design follow up studies to define function of predicted genes or sequence variants. We are currently in the fifth year of developing rat models for investigators to validate human variation and study function and mechanism for genes implicated in heart, lung and blood disorders. The Gene Editing Rat Resource Center (GERRC, http://rgd.mcw.edu/wg/custom_rats/gerrc) is an R24 grant funded by NHLBI that enables us to utilize an already existing infrastructure of personnel, expertise in gene editing, embryo microinjection, high‐throughput genotyping, sequencing, cryopreservation and rat distribution channels to generate and provide novel and important rat models to many of these investigators. An External Advisory Board (EAB) assesses our progress and, moreover, conducts a scientific merit review of all applications to select the genes and effectively use the resources of the R24 nominated by the scientific community. Primarily through the use of the CRISPR/Cas9 nuclease system, we are producing custom knockout, knockin and transgenic rat models by applying pronuclear microinjection of in vivo‐transcribed mRNAs encoding them into rat embryos. The resulting offspring are screened for mutations using a Cel‐I assay, and the resulting mutants TOPO cloned and validated by sequencing. To date, we have transferred over 19,570 microinjected embryos into the oviducts of pseudo‐pregnant Sprague‐Dawley recipient females resulting in 4000+ live‐born pups of which 3400+ have been screened for mutagenesis of the target locus. Of these, we have successfully generated ~630 pups containing mutations in 95 genes in 16 inbred, outbred, consomic and congenic rat strains (Dark Agouti [DA/MolTac], Dahl Salt‐Sensitive [SS/JrHsd/Jr/Mcwi and SS/JrHsdMcwiCrl], Wistar Kyoto [WKY/NCrl], Lewis [LEW/Crl], T2DN/Mcwi, Spontaneously Hypertensive (SHR/NCrl), Spontaneously Hypertensive Stroke Prone [SHRSP/A3NCrl], SS.BN‐ (D13Rat124‐ Scor13_3694), SS‐Chr 13BN/McwiCrl, LH‐17LN, Fawn‐hooded Hypertensive [FHH/EurMcwi] and FHH‐Chr 3BN/Mcwi, Crl:SD, FHH.PCK‐(D9Rat35‐D9Rat70)/Mcwi). Heterozygous pups are distributed to the requesting investigator and then, eventually, made available to the rat research community prior to sperm cryopreservation. Currently, 63 mutant strains have been transferred out and 43 in various stages of breeding prior to distribution.Support or Funding InformationNational Heart, Lung, and Blood Institute of the National Institutes of Health, R24HL114474This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.