A fluid-to-solid jamming transition underlies vertebrate body axis elongation.
A fluid-to-solid jamming transition underlies vertebrate body axis elongation.
复制标题
DOI：
10.1038/s41586-018-0479-2
复制
发表时间：
2018-09
期刊：
影响因子：
64.8
通讯作者：
Campàs O
中科院分区：
文献类型：
--
作者：
Mongera A;Rowghanian P;Gustafson HJ;Shelton E;Kealhofer DA;Carn EK;Serwane F;Lucio AA;Giammona J;Campàs O
就像粘土成型或玻璃吹制一样，雕刻生物结构需要组成材料像流体一样局部流动，同时保持整体机械完整性，就像固体一样。无序的软材料，如泡沫，乳液和胶体悬浮液，从流体状切换到固体状的行为在堵塞过渡。类似地，细胞集合体已被证明在2D和3D中显示玻璃态动力学，并在培养的上皮单层中堵塞，这些行为最近在理论上被预测并被提出影响哮喘病理生物学和肿瘤进展。然而，目前尚不清楚这些看似普遍的行为是否发生在体内，特别是它们是否在胚胎形态发生过程中发挥任何功能作用。通过结合直接在体内测量的组织力学与细胞动力学分析，我们表明，在脊椎动物体轴伸长，后部组织经历了一个拥挤的过渡，从流体样的行为在延伸端，中胚层祖细胞区（MPZ），固体样的行为在presomitic中胚层（PSM）。我们发现了一个前后，N-钙粘蛋白依赖的梯度屈服应力，提供了越来越多的机械完整性的PSM，符合组织从湿润过渡到干燥泡沫状架构。我们的结果表明，细胞规模的应力波动迅速（~1分钟），使细胞重排并有效地“融化”生长端的组织。在超细胞尺度上的持续（>0.5小时）应力，而不是细胞尺度应力，引导流体样组织区域中的形态发生流动。单向轴延伸由报告的PSM硬化维持，其在成熟之前的重塑期间机械地支撑后部流体样组织。类流体和类固体组织状态的时空控制可能代表胚胎形态发生的一般物理机制。
Just as in clay molding or glass blowing, sculpting biological structures requires the constituent material to locally flow like a fluid while maintaining overall mechanical integrity like a solid. Disordered soft materials, such as foams, emulsions and colloidal suspensions, switch from fluid-like to solid-like behaviors at a jamming transition. Similarly, cell collectives have been shown to display glassy dynamics in 2D and 3D and jamming in cultured epithelial monolayers, behaviors recently predicted theoretically and proposed to influence asthma pathobiology and tumor progression. However, it is unknown if these seemingly universal behaviors occur in vivo and, specifically, if they play any functional role during embryonic morphogenesis. By combining direct in vivo measurements of tissue mechanics with analysis of cellular dynamics, we show that during vertebrate body axis elongation, posterior tissues undergo a jamming transition from a fluid-like behavior at the extending end, the mesodermal progenitor zone (MPZ), to a solid-like behavior in the presomitic mesoderm (PSM). We uncover an anteroposterior, N-cadherin-dependent gradient in yield stress that provides increasing mechanical integrity to the PSM, consistent with the tissue transiting from a wetter to a dryer foam-like architecture. Our results show that cell-scale stresses fluctuate rapidly (~1 min), enabling cell rearrangements and effectively ‘melting’ the tissue at the growing end. Persistent (>0.5 h) stresses at supracellular scales, rather than cell-scale stresses, guide morphogenetic flows in fluid-like tissue regions. Unidirectional axis extension is sustained by the reported PSM rigidification, which mechanically supports posterior, fluid-like tissues during remodeling prior to their maturation. The spatiotemporal control of fluid-like and solid-like tissue states may represent a generic physical mechanism of embryonic morphogenesis.
登录
查看更多内容
影响因子：
64.8
作者：
Martin, Adam C.;Kaschube, Matthias;Wieschaus, Eric F.
通讯作者：
Wieschaus, Eric F.
影响因子：
4.6
作者：
Lawton, Andrew K.;Nandi, Amitabha;Holley, Scott A.
通讯作者：
Holley, Scott A.
影响因子：
--
作者：
Kimelman D
通讯作者：
Kimelman D
DOI：
10.1038/nrg3513
发表时间：
2013-10
期刊：
Nature reviews. Genetics
影响因子：
--
作者：
通讯作者：
--
影响因子：
64.8
作者：
通讯作者：
--