TCreERT2, a Transgenic Mouse Line for Temporal Control of Cre-Mediated Recombination in Lineages Emerging from the Primitive Streak or Tail Bud
TCreERT2, a Transgenic Mouse Line for Temporal Control of Cre-Mediated Recombination in Lineages Emerging from the Primitive Streak or Tail Bud
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DOI：
10.1371/journal.pone.0062479
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发表时间：
2013-04-30
期刊：
影响因子：
3.7
通讯作者：
Lewandoski, Mark
中科院分区：
文献类型：
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作者：
Anderson, Matthew J.;Naiche, L. A.;Lewandoski, Mark
通过使用遗传工具，如tcr小鼠系，对轴延伸和体细胞发生的研究取得了很大进展。在这一细胞系中，Cre受T （Brachyury）启动子片段控制，该启动子在原始条纹和尾芽内的祖细胞中活跃，并随着胚胎轴的延伸从这些组织中产生谱系。然而，由于tcree介导的重组发生在发育早期，基因失活可能导致轴截短，从而阻碍了对后期或更多后部组织中基因功能的研究。为了解决这一限制，我们已经产生了一个可诱导的TCreERT2转基因小鼠系，称为TCreERT2，它提供了时间控制，通过他莫昔芬管理，在整个发育过程中从原始条纹或尾芽出现的所有细胞。在没有他莫昔芬的情况下，TCreERT2的活性几乎是沉默的，而在他莫昔芬的存在下，从E7.5到E13.5的新生中胚层几乎完全重组。我们展示了TCreERT2线在确定后轴延伸率和体体形成率方面的效用，从而为此类测量提供了第一个体内工具。为了测试TCreERT2对基因操作的有用性，我们证明了通过TCreERT2诱导的β - catenin的早期缺失可以复制tcree介导的β - catenin缺陷的缺失，而后期的诱导绕过了这种早期表型，并在更多的尾端组织中产生类似的缺陷。TCreERT2为在整个发育过程中控制新兴胚胎谱系的基因表达提供了一种有用的新工具。
The study of axis extension and somitogenesis has been greatly advanced through the use of genetic tools such as the TCre mouse line. In this line, Cre is controlled by a fragment of the T (Brachyury) promoter that is active in progenitor cells that reside within the primitive streak and tail bud and which give rise to lineages emerging from these tissues as the embryonic axis extends. However, because TCre-mediated recombination occurs early in development, gene inactivation can result in an axis truncation that precludes the study of gene function in later or more posterior tissues. To address this limitation, we have generated an inducible TCre transgenic mouse line, called TCreERT2, that provides temporal control, through tamoxifen administration, in all cells emerging from the primitive streak or tail bud throughout development. TCreERT2 activity is mostly silent in the absence of tamoxifen and, in its presence, results in near complete recombination of emerging mesoderm from E7.5 through E13.5. We demonstrate the utility of the TCreERT2 line for determining rate of posterior axis extension and somite formation, thus providing the first in vivo tool for such measurements. To test the usefulness of TCreERT2 for genetic manipulation, we demonstrate that an early deletion of beta-Catenin via TCreERT2 induction phenocopies the TCre-mediated deletion of beta-Catenin defect, whereas a later induction bypasses this early phenotype and produces a similar defect in more caudal tissues. TCreERT2 provides a useful and novel tool for the control of gene expression of emerging embryonic lineages throughout development.