ESCs injected into the 8-cell stage mouse embryo modify pattern of cleavage and cell lineage specification
ESCs injected into the 8-cell stage mouse embryo modify pattern of cleavage and cell lineage specification
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DOI：
10.1016/j.mod.2016.06.002
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发表时间：
2016-08-01
影响因子：
2.6
通讯作者：
Suwinska, Aneta
中科院分区：
文献类型：
--
作者：
Humiecka, Monika;Krupa, Magdalena;Suwinska, Aneta
在小鼠胚胎发生过程中，细胞命运的初始规格取决于8- 16-和16- 32-细胞阶段过渡期间的分裂类型。卵裂球的保守分裂产生两个极性外子细胞，它们是滋养外胚层（TE）的前体，而分化分裂产生一个极性外细胞和一个非极性内细胞（假定的内细胞团- ICM）。我们推测分裂的类型可能取决于胚胎卵裂球之间的相互作用。为了研究这些相互作用的修饰是否影响分裂，我们分析了通过将不同数量的小鼠胚胎干细胞（ESC）注射到8细胞胚胎中获得的嵌合胚胎中的卵裂球分裂和细胞谱系特化的模式。由于胚胎干细胞只在嵌合胚泡的ICM中生长，它们在我们的模型中模拟了额外的内细胞。我们发现，ESCs的引入减少了在8- 16细胞阶段过渡的内部非极性卵裂球的数量，并减少了在囊胚形成过程中宿主胚胎来源的ICM细胞的数量。此外，我们发现，内卵裂球的比例和他们的命运（EPI或PE）在嵌合囊胚是依赖于胚胎干细胞注射的数量。我们的研究结果表明，存在一种调节机制，它将内细胞的数量与卵裂过程中保守与分化卵裂球分裂的比例联系起来，从而决定了它们的发育命运。(C)2016爱思唯尔爱尔兰有限公司版权所有。
During mouse embryogenesis initial specification of the cell fates depends on the type of division during 8- to 16- and 16- to 32-cell stage transition. A conservative division of a blastomere creates two polar outer daughter cells, which are precursors of the trophectoderm(TE), whereas a differentiative division gives rise to a polar outer cell and an apolar inner (the presumptive inner cell mass - ICM) cell. We hypothesize that the type of division may depend on the interactions between blastomeres of the embryo. To investigate whether modification of these interactions influences divisions, we analyzed the pattern of blastomere division and cell lineage specification in chimeric embryos obtained by injection of a different number of mouse embryonic stem cells (ESCs) into 8-cell embryos. As the ESCs populate only the ICM of the resulting chimeric blastocysts, they emulated in our model additional inner cells. We found that introduction of ESCs decreased the number of inner, apolar blastomeres at the 8- to 16-cell stage transition and reduced the number of ICM cells of host embryo-origin during formation of the blastocyst. Moreover, we showed that the proportion of inner blastomeres and their fate (EPI or PE) in chimeric blastocysts was dependent on the number of ESCs injected. Our results suggest the existence of a regulative mechanism, which links number of inner cells with a proportion of conservative vs. differentiative blastomere divisions during the cleavage and thus dictates their developmental fate. (C) 2016 Elsevier Ireland Ltd. All rights reserved.