Warga R M, Nüsslein-volhard C
Abteilung für Genetics, Max-Planck-Institut für Entwicklungsbiologie, Spemannstrasse 35, Tübingen, 72706, Germany.
Dev Biol. 1998 Nov 1;203(1):116-21. doi: 10.1006/dbio.1998.9022.
The dorsal marginal zone of the zebrafish blastula, equivalent to the amphibian Spemann organizer, is destined to become the tissues of the notochord and prechordal plate. Preceding gastrulation in the zebrafish, we find that these future mesendodermal cells acquire a cohesive cell behavior characterized by flattening and maximization of intercellular contacts, somewhat resembling cell compaction in mouse blastocysts. This behavior may suppress cell intermingling. Surprisingly, this blastula cell compaction requires normal function of spadetail, a gene known to be necessary for the dorsal convergent cell movement of paraxial mesoderm later in the gastrula. We propose that spadetail-dependent cell compaction subtly controls the early mixing and dispersal of dorsal cells that coalesce into the prospective organizer region. This early process may be necessary for the correct location of the boundary separating axial and paraxial cells.
斑马鱼囊胚的背侧边缘区，相当于两栖动物的施佩曼组织者，注定会形成脊索和前索板的组织。在斑马鱼原肠胚形成之前，我们发现这些未来的中内胚层细胞获得了一种凝聚性的细胞行为，其特征是细胞变平并使细胞间接触最大化，有点类似于小鼠囊胚中的细胞紧实化。这种行为可能会抑制细胞混合。令人惊讶的是，这种囊胚细胞紧实化需要spadetail基因的正常功能，该基因已知在原肠胚后期对于近轴中胚层的背侧汇聚细胞运动是必需的。我们提出，依赖spadetail的细胞紧实化微妙地控制着背侧细胞的早期混合和扩散，这些细胞会合并形成预期的组织者区域。这个早期过程对于正确定位分隔轴旁细胞和近轴细胞的边界可能是必要的。
