Body axis determination during early development in amphibians.
Body axis determination during early development in amphibians.
复制标题
两栖动物早期发育过程中体轴的确定。
DOI：
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发表时间：
1992
期刊：
影响因子：
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通讯作者：
P. Savard
中科院分区：
文献类型：
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作者：
P. Savard
身体主轴的规范是一种基于细胞通讯的现象，是胚胎发育的早期关键事件之一。受精后，两栖动物卵会重组其细胞质内容物，从而形成未来身体的背腹轴。母体成分的异质分布仅在几次有丝分裂后就赋予了细胞区域化。直到 4000 个细胞阶段的发育几乎完全依靠母体材料进行，在此期间，染色质进行重塑，以在胚胎的各个区域建立特定的基因表达。这个阶段的受精卵已经进行了细胞相互作用，导致中胚层的形成和区域化。然后，背侧中胚层成分诱导斯佩曼组织者的形成，这是一种直接参与胚胎前后轴（从头到尾）规范的结构。对这些现象的分子分析可以鉴定具有规范因子典型特征的生长因子样和转录因子样蛋白质。我们将回顾这些分子的最新进展，并将讨论视黄酸作为后验剂的假定作用。
The specification of the main axes of the body is a phenomenon based on cell communication and is among the early crucial events of embryonic development. Upon fertilization, the amphibian egg reorganizes its cytoplasmic content, leading to the establishment of the future dorsal-ventral axis of the body. Heterogeneous distribution of maternal components confers cellular regionalization after only a few mitoses. Development up to the 4000-cell stage proceeds almost entirely on maternal materials, and during this period there is remodeling of the chromatin to set up specific gene expression in various regions of the embryo. The zygote at this stage has already undertaken cellular interactions leading to mesoderm formation and regionalization. Dorsal mesodermal components then induce the formation of the Spemann's organizer, a structure directly involved in the specification of the anterior-posterior axis of the embryo (head to tail). Molecular analysis of these phenomena has allowed the identification of growth-factor-like and transcription-factor-like proteins that have characteristics typical of specification factors. We will review the recent advances on these molecules and will also discuss the putative role of retinoic acid as a posteriorizing agent.