Data for Comparison of two lines of tauGFP transgenic mice designed for lineage tracing

The data are numerical data used to produce some figures and tables for a manuscript comparing two lines of tauGFP transgenic mice designed for lineage tracing. Study Abstract: The tauGFP reporter fusion protein is produced nearly ubiquitously by the TgTP6.3 transgene in TP6.3 mice and its localisation to microtubules offers some advantages over soluble GFP as a lineage marker. However, TgTP6.3Tg/Tg homozygotes are not viable and TgTP6.3Tg/- hemizygotes are smaller than wild-type. TP6.4 mice carry the TgTP6.4 transgene, which was produced with the same construct used to generate TgTP6.3, so we investigated whether TgTP6.4 had any advantages over TgTP6.3. Although TgTP6.4Tg/Tg homozygotes died before weaning, TgTP6.4Tg/- hemizygotes were viable and fertile and only males were significantly lighter than wild-type. The TgTP6.4 transgene produced the tauGFP fusion protein by the 2-cell stage and it was widely expressed in adults but tauGFP fluorescence was weak or absent in several tissues, including some neural tissues. The TgTP6.4 transgene expression pattern changed over several years of breeding and mosaic transgene expression became increasingly common in all expressing tissues. Although mosaic expression makes the TgTP6.4 transgene unsuitable for use as a conventional cell lineage marker, mosaicism provides a useful system for visualising clonal lineages that arise during development or maintenance of adult tissues. Lineages in the adrenal cortex of TgTP6.4Tg/- hemizygotes were qualitatively and quantitatively comparable to lineages reported previously for other mosaic transgenic mice, X-inactivation mosaics and chimaeras. Mosaicism occurred less frequently in TP6.3 than TP6.4 mice and was only observed in the corneal epithelium and adrenal cortex. Such differences in the occurrence of mosaicism between related transgenic lines might provide a useful system for investigating the mechanism of transgene silencing.

本数据集为用于制作一篇对比两款设计用于谱系示踪（lineage tracing）的tauGFP转基因小鼠（tauGFP transgenic mice）品系的学术研究稿件的部分图表的数值数据。研究摘要如下：TP6.3小鼠体内的TgTP6.3转基因（TgTP6.3 transgene）几乎可遍在表达tauGFP报告融合蛋白（tauGFP reporter fusion protein）；相较于可溶性绿色荧光蛋白（soluble GFP），该融合蛋白定位于微管（microtubules），作为谱系标记物具备一定优势。但TgTP6.3Tg/Tg纯合子（homozygotes）无法存活，而TgTP6.3Tg/-半合子（hemizygotes）的体型小于野生型（wild-type）个体。TP6.4小鼠携带TgTP6.4转基因（TgTP6.4 transgene），该转基因的构建载体与TgTP6.3的构建载体一致，因此本研究探究了TgTP6.4相较于TgTP6.3是否具备更优特性。尽管TgTP6.4Tg/Tg纯合子在断奶前死亡，但TgTP6.4Tg/-半合子可正常存活并繁育，且仅雄性个体的体重显著低于野生型。TgTP6.4转基因可在2细胞期（2-cell stage）表达tauGFP融合蛋白，且在成年小鼠体内广泛分布，但在包括部分神经组织在内的多种组织中，tauGFP荧光信号较弱甚至无法检测到。经过数年繁育，TgTP6.4转基因的表达模式发生改变，转基因嵌合表达（mosaic transgene expression）在所有表达该转基因的组织中的发生率逐渐升高。尽管嵌合表达使得TgTP6.4转基因不适用于常规细胞谱系标记，但嵌合现象（mosaicism）为可视化发育过程或成年组织维持过程中产生的克隆谱系（clonal lineages）提供了实用的研究体系。TgTP6.4Tg/-半合子肾上腺皮质（adrenal cortex）内的克隆谱系在定性与定量层面，均与此前报道的其他嵌合转基因小鼠、X染色体失活嵌合体（X-inactivation mosaics）以及嵌合体（chimaeras）的克隆谱系相当。TP6.3小鼠的嵌合现象发生率低于TP6.4小鼠，且仅在角膜上皮（corneal epithelium）与肾上腺皮质中可观测到该现象。相关转基因品系间的嵌合现象发生率差异，可为探究转基因沉默（transgene silencing）的机制提供有效的研究体系。