Cell lineage of zebrafish blastomeres. III. Clonal analyses of the blastula and gastrula stages.
Cell lineage of zebrafish blastomeres. III. Clonal analyses of the blastula and gastrula stages.
复制标题
斑马鱼卵裂球的细胞谱系。
作者：
C. B. Kimmel;R. D. Law
斑马鱼（Brachydanio rerio）胚胎中卵裂球的早期谱系已被描述。由于胚胎的光学清晰度，通过许多细胞分裂，可以直接通过显微镜观察所选细胞的谱系。此外，它显示在这里，荧光分子荧光素-葡聚糖和罗丹明-辣根过氧化物酶可以用作细胞谱系示踪剂，标记的克隆后代的创始卵裂球。标记的细胞可以很容易地在活胚胎中可视化，并且利用灵敏的摄像机来放大荧光，可以在细胞分裂和迁移时重复检查相同的克隆。从单个卵裂球下降的细胞在囊胚期结束时保持紧密结合在一起。当外胚开始时（早期原肠胚），标记克隆中的细胞分散并分散在未标记的细胞中。已经观察到，相对于早期卵裂平面，胚胎中线（由胚盾在原肠胚中的位置决定）没有不变的映射。这一发现表明，在斑马鱼胚胎中，一个细胞将占据的区域并不是由细胞的早期等位基因决定的。
Aspects of the early lineages of blastomeres in the embryo of the zebrafish, Brachydanio rerio have been described. Because of the optical clarity of the embryo, lineages of selected cells can be followed directly by microscopy through many cell divisions. Also, it is shown here that the fluorescent molecules fluorescein-dextran and rhodamine-horseradish peroxidase can be used as cell lineage tracers, marking the clonal progeny of founding blastomeres. The labeled cells can be easily visualized in the live embryo, and utilizing a sensitive video camera to amplify fluorescence, the same clone may be examined repeatedly while the cells divide and migrate. Cells that descend from a single blastomere remain closely associated together through the end of the blastula stage. At the time when epiboly begins (early gastrula) cells in the labeled clone scatter and become dispersed among unlabeled cells. It has been observed that there is no invariant mapping of the embryo's midline (determined by the position of the embryonic shield in the gastrula) with respect to the early planes of cleavage. This finding shows that in the zebrafish the region of the embryo that a cell will occupy is not specified by the cell's early ancestory.