Paternal repression of the imprinted mouse Igf2r locus occurs during implantation and is stable in all tissues of the post-implantation mouse embryo
Paternal repression of the imprinted mouse Igf2r locus occurs during implantation and is stable in all tissues of the post-implantation mouse embryo
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DOI：
10.1016/s0925-4773(96)00630-2
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发表时间：
1997-01-01
影响因子：
2.6
通讯作者：
Barlow, DP
中科院分区：
文献类型：
--
作者：
Lerchner, W;Barlow, DP
胰岛素样生长因子2型受体，也称为阳离子非依赖性甘露糖-6-磷酸受体（Igf2r），是一种印迹基因，在妊娠中期小鼠胚胎父系遗传等位基因上受到抑制。我们利用一个LacZ报告基因，瞄准内源基因，研究了父本等位基因抑制的发育时间、组织特异性和稳定性。LacZ在着床前和着床后胚胎中的表达模式证实了Igf2r仅在着床后呈现单等位基因表达。此外，我们在这里表明，Igf2r在E4.5时在着床前胚胎的所有细胞中显示双等位基因表达，并且在E6.5时，在着床后早期胚胎的所有组织中明显存在单等位基因表达。印迹表达在胚胎发育后期得以维持，在胚胎发育的E13.5期没有组织能逃脱印迹。因此，Igf2r的单等位基因表达发生在着床期的所有细胞中，并且在胚胎发育后期的所有组织中维持父本抑制。(C) 1997爱思唯尔科学爱尔兰有限公司
The insulin-like growth factor type 2 receptor, also known as the cation independent mannose-6-phosphate receptor (Igf2r) is an imprinted gene, which is repressed on the paternally inherited allele in midgestation mouse embryos. We have used a LacZ reporter gene, targeted into the endogenous gene, to investigate the developmental timing, tissue specificity and stability of the repression of the paternal allele. The LacZ expression pattern in pre- and post-implantation embryos, confirmed that Igf2r shows monoallelic expression only after implantation. We show here, additionally, that Igf2r shows biallelic expression in all cells of the preimplantation embryo at E4.5, and, that monoallelic expression is clearly present in all tissues at E6.5, in the early post-implantation embryo. Imprinted expression is maintained in later embryonic development and no tissue was observed to escape imprinting up to E13.5 of development. Thus, for Igf2r, the onset of monoallelic expression occurs in all cells during the implantation period and paternal repression is maintained in all tissues of the late developing embryo. (C) 1997 Elsevier Science Ireland Ltd.