title: Derivation of rat embryonic stem cells and generation of protease-activated receptor-2 knockout rats.
abstract: One of the remarkable achievements in knockout (KO) rat production reported during the period 2008-2010 is the derivation of authentic embryonic stem (ES) cells from rat blastocysts using a novel culture medium containing glycogen synthase kinase 3 and mitogen-activated protein kinase kinase inhibitors (2i medium). Here, we report gene-targeting technology via homologous recombination in rat ES cells, demonstrating its use through production of a protease-activated receptor-2 gene (Par-2) KO rat. We began by generating germline-competent ES cells from Dark Agouti rats using 2i medium. These ES cells, which differentiate into cardiomyocytes in vitro, can produce chimeras with high ES cell contribution when injected into blastocysts. We then introduced a targeting vector with a neomycin-resistant gene driven by the CAG promoter to disrupt Par-2. After a 7-day drug selection, 489 neomycin-resistant colonies were obtained. Following screening by polymerase chain reaction (PCR) genotyping and quantitative PCR analysis, we confirmed three homologous recombinant clones, resulting in chimeras that transmitted the Par-2 targeted allele to offspring. Par-2 KO rats showed a loss of Par-2 messenger RNA expression in their stomach cells and a lack of PAR-2 mediated smooth muscle relaxation in the aorta as indicated by pharmacological testing. Compared with mice, rats offer many advantages in biomedical research, including a larger body size; consequently, they are widely used in scientific investigation. Thus, the establishment of a gene-targeting technology using rat ES cells will be a valuable tool in human disease model production and drug discovery.
authors: Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 2-26-1 Muraoka-higashi, Fujisawa City, Kanagawa 251-8555, Japan. Yamamoto_Satoshi2@takeda.co.jp
authors: Satoshi
authors: S
authors: Yamamoto
authors: Mitsugu
authors: M
authors: Nakata
authors: Reiko
authors: R
authors: Sasada
authors: Yuki
authors: Y
authors: Ooshima
authors: Takashi
authors: T
authors: Yano
authors: Tadahiro
authors: T
authors: Shinozawa
authors: Yasuhiro
authors: Y
authors: Tsukimi
authors: Michiyasu
authors: M
authors: Takeyama
authors: Yoshio
authors: Y
authors: Matsumoto
authors: Tadatoshi
authors: T
authors: Hashimoto
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001755:Blastocyst / Q000166:cytology; D018929:Cell Culture Techniques; D053595:Embryonic Stem Cells; D055786:Gene Knockout Techniques; D018390:Gene Targeting; D059765:Homologous Recombination; D032383:Myocytes, Cardiac / Q000166:cytology; D051381:Rats; D044464:Receptor, PAR-2 / Q000235:genetics*
chemical_list: D044464:Receptor, PAR-2