Desprat Nicolas, Supatto Willy, Pouille Philippe-Alexandre, Beaurepaire Emmanuel, Farge Emmanuel
Mechanics and Genetics of Embryonic and Tumoral Development Group, UMR168 CNRS, Institut Curie, 11 rue Pierre et Marie Curie, F-75005, Paris, France.
Mechanics and Genetics of Embryonic and Tumoral Development Group, UMR168 CNRS, Institut Curie, 11 rue Pierre et Marie Curie, F-75005, Paris, France; Laboratory for Optics and Biosciences, Ecole Polytechnique, CNRS and INSERM U 696, 91128 Palaiseau, France.
Dev Cell. 2008 Sep;15(3):470-477. doi: 10.1016/j.devcel.2008.07.009.
Mechanical deformations associated with embryonic morphogenetic movements have been suggested to actively participate in the signaling cascades regulating developmental gene expression. Here we develop an appropriate experimental approach to ascertain the existence and the physiological relevance of this phenomenon. By combining the use of magnetic tweezers with in vivo laser ablation, we locally control physiologically relevant deformations in wild-type Drosophila embryonic tissues. We demonstrate that the deformations caused by germ band extension upregulate Twist expression in the stomodeal primordium. We find that stomodeal compression triggers Src42A-dependent nuclear translocation of Armadillo/beta-catenin, which is required for Twist mechanical induction in the stomodeum. Finally, stomodeal-specific RNAi-mediated silencing of Twist during compression impairs the differentiation of midgut cells, resulting in larval lethality. These experiments show that mechanically induced Twist upregulation in stomodeal cells is necessary for subsequent midgut differentiation.
与胚胎形态发生运动相关的机械变形被认为积极参与调节发育基因表达的信号级联反应。在此，我们开发了一种合适的实验方法来确定这一现象的存在及其生理相关性。通过将磁性镊子的使用与体内激光消融相结合，我们在野生型果蝇胚胎组织中局部控制生理相关的变形。我们证明，胚带延伸引起的变形会上调口凹原基中Twist的表达。我们发现，口凹压缩会触发Src42A依赖的犰狳/β-连环蛋白核转位，这是口凹中Twist机械诱导所必需的。最后，在压缩过程中，口凹特异性RNAi介导的Twist沉默会损害中肠细胞的分化，导致幼虫死亡。这些实验表明，口凹细胞中机械诱导的Twist上调对于随后的中肠分化是必要的。
