Kwon Gloria S, Hadjantonakis Anna-Katerina
Developmental Biology Program, Sloan-Kettering Institute, New York, New York 10021, USA.
Genesis. 2007 Apr;45(4):208-17. doi: 10.1002/dvg.20293.
Expression of T-box family member Eomesodermin (Tbr2) is spatiotemporally restricted in the mouse embryo; initially expressed in extraembryonic lineages in the sequential progression from the trophectoderm of the blastocyst, its derivatives the extraembryonic ectoderm, and thereafter the chorion, in addition to the visceral endoderm and primitive streak at gastrula stages, and the telencephalon at later stages. We describe the spatiotemporal expression of GFP in embryos of a Tg(Eomes::GFP) BAC transgenic strain, and have compared it with the localization of endogenous Eomes transcripts and protein. Our analysis reveals the following: (1) robust easily visualized reporter expression in live hemizygous transgenic embryos, (2) increased levels of expression in live homozygous transgenic embryos that are compatible with embryo viability, and (3) a close correlation between endogenous Eomes and GFP reporter expression in BAC transgenic embryos. These features establish the Tg(Eomes::GFP) BAC transgenic strain as a novel reagent for both live imaging and the isolation of Eomes expressing cells from specific locations within the embryo.
T-box家族成员Eomesodermin（Tbr2）在小鼠胚胎中的表达具有时空限制性；最初在胚外谱系中表达，从囊胚的滋养外胚层开始依次进展，其衍生物胚外外胚层，此后是绒毛膜，此外在原肠胚阶段的脏内胚层和原条，以及后期的端脑也有表达。我们描述了GFP在Tg(Eomes::GFP) BAC转基因品系胚胎中的时空表达，并将其与内源性Eomes转录本和蛋白质的定位进行了比较。我们的分析揭示了以下几点：（1）在活的半合子转基因胚胎中报告基因表达强烈且易于观察；（2）在与胚胎活力相容的活的纯合子转基因胚胎中表达水平增加；（3）BAC转基因胚胎中内源性Eomes和GFP报告基因表达之间密切相关。这些特性使Tg(Eomes::GFP) BAC转基因品系成为用于实时成像以及从胚胎内特定位置分离表达Eomes细胞的新型试剂。
