NHGRI/DIR Embryonic Stem Cell and Transgenic Mouse Core

NHGRI胚胎干细胞和转基因小鼠核心为NHGRI研究者提供共享服务。Core专门通过传统的转基因、胚胎干细胞靶向以及最近使用位点特异性核酸酶（CRISPR/Cas）进行基因组编辑来产生基因工程小鼠（GEM）。为了完成这项工作，Core在内部培育了90%用于生产GEM的动物。Core利用几种背景菌株来产生小鼠，并开发并鉴定了来自C57Bl/6J、C57Bl/6N、C57Bl/6白化、129S6Sv/Ev和129.B6（GFP）的胚胎干细胞。我们也有一群不同的Cre表达小鼠和其他转基因小鼠，这些小鼠被研究人员用于许多方案，从而通过为多个用户繁殖来最大化效率并减少小鼠数量。所有重要的老鼠都被冷冻保存在两个不同的地方，以备不时之需。所有输入小鼠都通过体外受精重新衍生到Core中。我们经常对小鼠进行基因分型，并采用了有效的方案来减少小鼠，试剂和时间。核心支持NHGRI研究人员进行基因靶向和转基因的构建设计，以及小鼠饲养的基本操作。该中心为NHGRI研究人员提供的其他服务包括ENU注射、畸胎瘤分析、胚胎采集和解剖、小鼠胚胎成纤维细胞的分离和诱导多能干细胞的生成。这些服务使NHGRI研究人员能够充分利用小鼠作为模型生物。因此，Core不仅生产小鼠，而且我们还促进并使研究人员能够在他们缺乏专业知识的领域进行小鼠实验。

The NHGRI Embryonic Stem Cell and Transgenic Mouse Core provides a shared service to NHGRI investigators. The Core specializes in generating genetically engineered mice (GEM) via conventional transgenesis, ES cell targeting, and more recently genome editing using site-specific nucleases (CRISPR/Cas). To do this work, the Core breeds, in-house, 90% of the animals to be used for generating GEM. The Core utilizes several background strains for generating mice and has developed and characterized embryonic stem cells from C57Bl/6J, C57Bl/6N, C57Bl/6 albino, 129S6Sv/Ev, and 129.B6(GFP). We also have a colony of various Cre expressing mice and other transgenics that are used by investigators across many protocols, thereby maximizing the efficiency and reducing mouse numbers by breeding for multiple users. All important mice are cryopreserved and stored in 2 separate locations for disaster purposes. All imported mice are rederived into the Core by in vitro fertilization. We routinely genotype mice and have adapted efficient protocols to minimize mice, reagents and time. The Core supports NHGRI investigators in construct design for gene targeting and transgenesis, and in basic manipulations of mouse husbandry. Other services provided by the Core to help serve NHGRI investigators include ENU injection, teratoma analysis, embryo harvest and dissection, isolation of mouse embryonic fibroblasts and generation of induced pluripotent stem cells. These services allow NHGRI investigators to take full advantage of the mouse as a model organism. Thus, the Core not only generates mice, but we facilitate and enable investigators to perform mouse experiments in areas where they have less expertise. The NHGRI Transgenic Core is at the forefront of a major increase in transgenic production using CRISPR/Cas gene-editing constructs via injection into oocytes. This technology is replacing the generation of conventional knockout mice using embryonic stem cells and has made the technology more user friendly to a variety of investigators and allows NHGRI to be at the cutting edge of this new and important genomic editing technology in mammalian models. The core generated targeted transgenics using the CRISPR/Cas system for over 75 constructs since January 2014. Additionally, there were over 100 transgenic lines cryopreserved due to the efficiency of CRISPR/Cas to generate multiple alleles.