The potential to differentiate epidermis is unequally distributed in the AB lineage during early embryonic development in C. elegans.
The potential to differentiate epidermis is unequally distributed in the AB lineage during early embryonic development in C. elegans.
复制标题
在线虫早期胚胎发育过程中，AB 谱系中表皮分化的潜力分布不均。
DOI：
10.1006/dbio.1994.1355
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发表时间：
1994
影响因子：
2.7
通讯作者：
Rothman,JH
中科院分区：
文献类型：
--
作者：
Gendreau,SB;Moskowitz,IP;Terns,RM;Rothman,JH
在早期的秀丽隐杆线虫胚胎中，大部分外胚层源自AB卵裂球，它是六个创始细胞之一。我们报告说，AB 谱系的第三分裂轮中产生了不等价的卵裂球。每个 AB 孙女细胞分裂产生一种细胞，该细胞有可能产生丰富的表皮，另一种细胞则主要产生神经系统。这种形成表皮的潜力的不均匀分布发生在通过激光消融所有其他细胞而分离的AB孙女中，或者在培养物中分离的AB卵裂球的发育过程中。该事件的保真度通常被来自 MS 始祖细胞的信号所掩盖，该细胞诱导中胚层，特别是 AB 后代。当激光细胞消融或 glp-1 基因突变阻止 MS 诱导时，AB 曾孙女的表皮命运图变得左右对称。细胞谱系分析表明，事实上，在没有 MS 诱导的情况下，AB 谱系变得完全左右对称。这解释了先前在 aglp-1 突变体中观察到的额外表皮细胞。我们的结果表明，线虫的表皮分化可能是由细胞自主机制控制的，该机制在AB发育过程中差异分配表皮电位，并且MS诱导在一定程度上通过克服这种电位而导致AB后代命运的左右不对称。
In the earlyCaenorhabditis elegansembryo most of the ectoderm arises from the AB blastomere, one of the six founder cells. We report that nonequivalent blastomeres are generated at the third division round in the AB lineage. Each AB granddaughter divides to produce one cell that has the potential to make abundant epidermis and one that instead produces primarily nervous system. This unequal distribution of the potential to make epidermis occurs in an AB granddaughter that is isolated by laser-ablation of all other cells or during the development of an isolated AB blastomere in culture. The fidelity of this event is normally masked by a signal from the MS founder cell, which induces mesoderm in particular AB descendants. When MS induction is prevented by laser cell-ablation or by a mutation in theglp-1gene, the epidermal fate map of the AB great granddaughters becomes left-right symmetrical. Cell lineage analyses demonstrate that, in fact, the AB lineage becomes entirely left-right symmetrical in the absence of MS induction. This accounts for the extra epidermal cells previously observed in aglp-1mutant. Our results suggest that epidermal differentiation in the nematode may be controlled by a cell-autonomous mechanism that differentially allocates epidermal potential during AB development and that MS induction generates the left-right asymmetry in the fates of AB descendants in part by overriding this potential.