High cell-autonomy of the anterior endomesoderm viewed in blastomere fate shift during regulative development in the isolated right halves of four-cell stage Xenopus embryos
High cell-autonomy of the anterior endomesoderm viewed in blastomere fate shift during regulative development in the isolated right halves of four-cell stage Xenopus embryos
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在四细胞阶段非洲爪蟾胚胎的分离右半部分的调节发育过程中，从卵裂球命运转变中观察到前内中胚层的高度细胞自主性
DOI：
10.1111/j.1440-169x.2012.01372.x
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发表时间：
2012
影响因子：
2.5
通讯作者：
Masaaki Koga
中科院分区：
文献类型：
--
作者：
Sharov AA;Nishiyama A(他6人);Masaaki Koga
Xenopus胚胎的分离的右半部分（RH）或左半部分（LH）可以进行调节，以形成比例均匀的幼虫。为了评估母体决定因素和细胞间相互作用的联合作用如何有助于形成比例均匀的幼虫，我们定量比较了正常幼虫和RH胚胎调节幼虫之间的四细胞期卵裂球命运。在正常幼虫中，右背侧卵裂球（RD）和右腹侧卵裂球（RV）的克隆位于单侧。与此相反，在调节幼虫：（i）RD克隆只占据前内中胚层（AE）的衍生物，符合没有RV后代在正常幼虫的衍生物。克隆双侧人口组织沿着背中线，其特征性地包括两个体节毗邻脊索的内侧区域，与右侧和前侧的百分比较高。(ii)RV克隆以牺牲其右侧贡献为代价广泛补偿了缺失的左侧，并且双侧占据了腹后区和背侧区，不包括AE衍生物。这个克隆相当大的人口，与改变方向，衍生物的左半胃腔顶板（GRP），左半GRP是必不可少的偏侧性确定。这些结果表明，AE中的高度细胞自主性构成了正常发育和调节发育的共同机制。在调节幼虫中，细胞-细胞相互作用使背侧的中线略微偏移，腹侧偏移的程度更大。GRP左半部分的细胞谱系差异可能导致该区域对母体决定因素的不同利用。
The isolated right half (RH) or left half (LH) ofXenopusembryos can undergo regulation so as to form well‐proportioned larvae. To assess how the combined actions of maternal determinants and cell–cell interactions contribute to form the well‐proportioned larvae, we quantitatively compared four‐cell stage blastomere fate between normal larvae and regulated larvae from RH embryos. In normal larvae, the clones of the right dorsal blastomere (RD) and right ventral blastomere (RV) were located unilaterally. In contrast, in regulated larvae: (i) the RD clone exclusively occupied the anterior endomesoderm (AE) derivatives, coinciding no RV progeny in those derivatives of normal larvae. The clone bilaterally populated tissues along the dorsal midline, which characteristically included the medial regions of both somites adjoining the notochord, with higher percentages on the right and anterior sides. (ii) The RV clone extensively compensated for the missing left side at the expense of its right side contribution, and bilaterally occupied the ventroposterior and also dorsal regions excluding the AE derivatives. This clone considerably populated, with altered orientations, the derivatives of the left half gastrocoel roof plate (GRP), the left half GRP being essential for laterality determination. These results show that the high cell‐autonomy in the AE constitutes a mechanism common to both normal and regulative development. In regulated larvae, cell–cell interactions shifted the midlines on the dorsal side slightly and the ventral side to a greater extent. The cell lineage difference in the left half GRP could result in a different utilization of maternal determinants in that area.