The Geometric Basis of Epithelial Convergent Extension.
The Geometric Basis of Epithelial Convergent Extension.
复制标题
上皮会聚延伸的几何基础。
DOI：
10.1101/2023.05.30.542935
复制
发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Shraiman,BorisI
中科院分区：
文献类型：
--
作者：
Brauns,Fridtjof;Claussen,NikolasH;Wieschaus,EricF;Shraiman,BorisI
动物发育过程中上皮的形状变化，如趋同延伸，是通过单个细胞协调一致的机械活动来实现的。虽然对相应的大规模组织流动及其遗传驱动因素了解很多，但细胞规模协调的问题仍未解决。我们认为这种协调可以从组织内的机械相互作用和瞬时力平衡的角度来理解。利用果蝇发育的全胚胎成像数据，我们研究了局部皮层张力平衡与细胞几何形状之间的关系。这揭示了主动张力和被动全局变形的局部正反馈如何解释协调的细胞重排。我们建立了一个连接细胞和组织尺度动力学的模型，并预测了总组织扩展对细胞堆积的初始各向异性和六边形顺序的依赖。我们的研究提供了对局部细胞尺度活动中全局组织形状编码的一般见解。组织流动是由皮层张力平衡的受控转化来解释的；正张力反馈驱动主动细胞插入；细胞插入的协调需要局部张力配置的秩序；张力动力学模型预测从初始细胞秩序开始的组织形状的总变化
Shape changes of epithelia during animal development, such as convergent extension, are achieved through concerted mechanical activity of individual cells. While much is known about the corresponding large scale tissue flow and its genetic drivers, the question of cell-scale coordination remains open. We propose that this coordination can be understood in terms of mechanical interactions and instantaneous force balance within the tissue. Using whole embryo imaging data forDrosophilagastrulation, we exploit the relation between balance of local cortical tension forces and cell geometry. This unveils how local positive feedback on active tension and passive global deformations account for coordinated cell rearrangements. We develop a model that bridges the cell and tissue scale dynamics and predicts the dependence of total tissue extension on initial anisotropy and hexagonal order of the cell packing. Our study provides general insight into the encoding of global tissue shape in local cell-scale activity.HighlightsTissue flow is explained by controlled transformation of cortical tension balancePositive tension feedback drives active cell intercalationCoordination of cell intercalation requires order in local tension configurationsTension dynamics model predicts total tissue shape change from initial cellular order