Krieg M, Arboleda-Estudillo Y, Puech P-H, Käfer J, Graner F, Müller D J, Heisenberg C-P
BIOTEC, Technische Universität Dresden, Tatzberg 47-51, 01307 Dresden, Germany.
Nat Cell Biol. 2008 Apr;10(4):429-36. doi: 10.1038/ncb1705. Epub 2008 Mar 23.
Understanding the factors that direct tissue organization during development is one of the most fundamental goals in developmental biology. Various hypotheses explain cell sorting and tissue organization on the basis of the adhesive and mechanical properties of the constituent cells. However, validating these hypotheses has been difficult due to the lack of appropriate tools to measure these parameters. Here we use atomic force microscopy (AFM) to quantify the adhesive and mechanical properties of individual ectoderm, mesoderm and endoderm progenitor cells from gastrulating zebrafish embryos. Combining these data with tissue self-assembly in vitro and the sorting behaviour of progenitors in vivo, we have shown that differential actomyosin-dependent cell-cortex tension, regulated by Nodal/TGFbeta-signalling (transforming growth factor beta), constitutes a key factor that directs progenitor-cell sorting. These results demonstrate a previously unrecognized role for Nodal-controlled cell-cortex tension in germ-layer organization during gastrulation.
了解发育过程中指导组织形成的因素是发育生物学最基本的目标之一。各种假说基于组成细胞的黏附性和机械特性来解释细胞分选和组织形成。然而，由于缺乏测量这些参数的合适工具，验证这些假说一直很困难。在此，我们使用原子力显微镜（AFM）来量化来自斑马鱼原肠胚外胚层、中胚层和内胚层祖细胞的黏附性和机械特性。将这些数据与体外组织自组装以及祖细胞在体内的分选行为相结合，我们发现由Nodal/TGFβ信号（转化生长因子β）调控的、依赖于肌动球蛋白的细胞皮层张力差异是指导祖细胞分选的关键因素。这些结果证明了Nodal控制的细胞皮层张力在原肠胚形成过程中胚层组织方面具有此前未被认识到的作用。
